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HomeMy WebLinkAbout20191205_Geotechnical Report_10-28-19COAST GEOTECHNICAL, INC. Geotechnical Engineering Investigation of Proposed New Residence at 2701 Circle Drive Newport Beach, California BY: COAST GEOTECHNICAL, INC. W. O. 582819-01, October 28, 2019 FOR: Mr. and Mrs. Gary Lisenbee 2701 Circle Drive Newport Beach, CA 92663 COAST GEOTECHNICAL, INC. 1200 West Commonwealth Ave., Fullerton, CA 92833 • Ph: (714) 870-1211 • Fax: (714) 870-1222 • e-mail: coastgeotec@sbcglobal.net October 29, 2019 Mr. and Mrs. Gary Lisenbee 2701 Circle Drive Newport Beach, CA 92663 Mr. and Mrs. Lisenbee: Subject: w.o. 582819-01 Geotechnical Engineering Investigation of Proposed New Residence at 2701 Circle Drive, Newport Beach, California Pursuant to your request, a geotechnical engineering investigation has been performed at the subject site. The purposes of the investigation were to determine the general engineering characteristics of the near surface soils on and underlying the site and to provide recommendations for the design of foundations and underground improvements. The conclusions and recommendations contained in this report are based upon the understanding of the proposed development and the analyses of the data obtained from our field and laboratory testing programs. This report completes our scope of geotechnical engineering services authorized by you in the August 13, 2019 proposal. SITE DEVELOPMENT It is our understanding that the existing site improvements are to be demolished and the site redeveloped with a two to three-story slab on grade residential structure. Structural loads are anticipated to be light. Significant grade changes are not anticipated. PURPOSE AND SCOPE OF SERVICES The scope of the study was to obtain subsurface information within the project site area and to provide recommendations pertaining to the proposed development and included the following: 1. A cursory reconnaissance of the site and surrounding areas. 2. Excavation of two exploratory borings to determine the near subsurface soil conditions and groundwater conditions. 3. Collection of representative bulk and/or undisturbed soil samples for laboratory analysis. 4. Laboratory analyses of soil samples including determination of in-situ and maximum density, in- situ and optimum moisture content, shear strength characteristics, expansion potential, and sulfate content. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 2 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 5. Preparation of this report presenting results of our investigation and recommendations of the proposed development. SITE CONDITIONS The project site is located at 2701 Circle Drive, City of Newport Beach, California, and is shown on the attached Site Vicinity Map, Figure 1. The parcel is near triangular in shape, near level, and bordered by Circle Drive to the south and east, an alley to the north, and a developed residential property to the west. The lot is currently developed with a single family residence, hardscape and landscape. The proposed site configuration is further shown on the Site Plan, Figure 2. FIELD INVESTIGATION The field investigation was performed on October 10, 2019, consisting of the excavation of a boring by limited access drilling equipment (for Boring No. 1) and a boring by hand auger equipment (for Boring No. 2) at the locations shown on the attached Site Plan, Plate 2. As excavations progressed, a representative from this office visually classified the earth materials encountered, and secured representative samples for laboratory testing. Geotechnical characteristics of subsurface conditions were assessed by either driving a split spoon ring sampler or an SPT sampler into the earth material. Undisturbed samples for detailed testing in our laboratory were obtained from Boring No. 2 by pushing or driving a sampling spoon into the earth material. A solid-barrel type spoon was used having an inside diameter of 2.5 inches with a tapered cutting tip at the lower end and a ball valve at the upper end. The barrel is lined with thin brass rings, each one inch in length. The spoon penetrated into the earth materials below the depth of borings approximately six inches. The central portion of this sample was retained for testing. All samples in their natural field condition were sealed in airtight containers and transported to the laboratory. Standard Penetration Test (SPT) was performed for Boring No. 1, based on ASTM D1586. The number of blows required for driving the sampler through three six-inch intervals is recorded. The sum of the number of blows required for driving the last two six-inch intervals is referred to as the standard penetration number "N". Samplers from Boring No. 1 were driven into the soil at the bottom of the borehole by means of hammer blows. The hammer blows are given at the top of the drilling rod. The blows are by a hammer weighing 140 pounds dropped a distance of 30 inches. Drive sampling was obtained at two feet intervals in accordance with City guidelines. Considering that the upper three feet of the pad area will be recompacted, SPT sampling commenced at three feet below grade. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 3 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 For liquefaction analysis, CE of 1.0 (for safety hammer), CB of 1.05 (for seven inch borehole diameter), and Cs of 1.2 ( for sampler without liners) are used to calculate corrected N values. EARTH MATERIALS Earth materials encountered within the exploratory borings were visually logged by a representative of COAST GEOTECHNICAL, INC. The earth materials encountered were classified as artificial fill underlain by native soils to the maximum depth explored. Artificial fills encountered consisted of silty, fine to medium-grained sand, with roots, brown in color, dry to damp and generally loose. The fills were encountered to a depth of about two feet below existing grade. Native soils encountered consisted of silty to clean, fine to medium-grained sand, light gray tan to yellow tan and gray in color, damp to wet and generally medium dense to dense to a maximum depth explored of twelve and one half feet. Logs of the exploratory borings are presented on the appended Plates B and C. The data presented on these logs is a simplification of actual subsurface conditions encountered and applies only at the specific boring locations, time and date excavated. It is not warranted to be representative of subsurface conditions at other times and locations. GROUNDWATER Groundwater was encountered at seven feet below existing ground surface during the field investigation. This groundwater level is subject to minor fluctuation due to tidal changes. Plate 1.2 in Appendix B shows the subject site area to have a historic high groundwater depth ofless than ten feet below existing ground surface. In our liquefaction and seismic settlement analyses, a groundwater elevation of five feet below ground surface is used for more conservative calculations in accordance with City policy. SEISMICITY Southern California is located in an active seismic region. Moderate to strong earthquakes can occur on numerous faults. The United States Geological Survey, California Division of Mines and Geology, private consultants, and universities have been studying earthquakes in Southern California for several decades. Early studies were directed toward earthquake prediction estimation of the effects of strong ground shaking. Studies indicate that earthquake prediction is not practical and not sufficiently accurate to benefit the general public. Governmental agencies are shifting their focus to earthquake resistant structures as opposed to prediction. The purpose of the code seismic design parameters is to prevent collapse during strong ground shaking. Cosmetic damage should be expected. Within the past 48 years, Southern California and vicinity have experienced an increase in seismic activity beginning with the San Francisco earthquake in 1971. In 1987, a moderate earthquake COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 4 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 struck the Whittier area and was located on a previously unknown fault. Ground shaking from this event caused substantial damage to the City of Whittier, and surrounding cities. The January 17, 1994, Northridge earthquake was initiated along a previously unrecognized fault below the San Fernando Valley. The energy released by the earthquake propagated to the southeast, northwest, and northeast in the form of shear and compression waves, which caused the strong ground shaking in portions of the San Fernando Valley, Santa Monica Mountains, Simi Valley, City of Santa Clarita, and City of Santa Monica. Southern California faults are classified as: active, potentially active, or inactive. Faults from past geologic periods of mountain building, but do not display any evidence of recent offset, are considered "inactive" or "potentially active". Faults that have historically produced earthquakes or show evidence of movement within the past 11,000 years are known as "active faults". There are no known active faults within the subject property, with the nearest being the Newport fuglewood Fault Zone and the San Joaquin Blind Thrust Fault. • Newport-Inglewood Fault Zone: The Newport-Inglewood Fault Zone is a broad zone of left- stepping en echelon faults and folds striking southeastward from near Santa Monica across the Los Angeles basin to Newport Beach. Altogether these various faults constitute a system more than 150 miles long that extends into Baja California, Mexico. Faults having similar trends and projections occur offshore from San Clemente and San Diego (the Rose Canyon and La Nacion Faults). A near-shore portion of the Newport-Inglewood Fault Zone was the source of the destructive 1933 Long Beach earthquake. The reported recurrence interval for a large event along this fault zone is 1,200 to 1,300 years with an expected slip of one meter. • San Joaquin Hills Blind Thrust Fault: The seismic hazards in Southern California have been further complicated with the recent realization that major earthquakes can occur on large thrust faults that are concealed at depths between 5 to 20 km, referred to as "blind thrusts." The uplift of the San Joaquin Hills is produced by a southwest dipping blind thrust fault that extends at least 14 km from northwestern Huntington Mesa to Dana Point and comes to within 2 km of the ground surface. Work by Grant et al. (1997 and 1999) suggest that uplift of the San Joaquin Hills began in the Late Quaternary and continues during the Holocene. Uplift rates have been estimated between 0.25 and 0.5 mm/yr. If the entire length of the fault ruptured, the earthquake has been estimated to generate an Mw 6.8 event. We are of the opinion that the more active Newport fuglewood fault is the causative fault for the subject site. The fault is located approximately two kilometers to the southwest. SEISMIC HAZARDS The potential hazards to be evaluated with regard to seismic conditions include fault rupture, landslides triggered by ground shaking, soil liquefaction, earthquake-induced vertical and lateral displacements, earthquake-induced flooding due to the failure of water containment structures, seiches, and tsunamis. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 5 Geotechnical Engineering Investigation Fault Rupture w. 0. 582819-01 October 29, 2019 The project is not located within a currently designated Alquist-Priolo Earthquake Zone (Bryant and Hart, 2007). No known active faults are mapped on the site. Based on this consideration, the potential for surface fault rupture at the site is considered to be remote. Ground Shaking The site is located in a seismically active area that has historically been affected by moderate to occasionally high levels of ground motion and site lies in relatively close proximity to several active faults; therefore, during the life of the proposed development, the property will probably experience moderate to occasionally high ground shaking from these fault zones, as well as some background shaking from other seismically active areas of the Southern California region. Design of structures by code is to maintain structural integrity not to prevent damage. Earthquake insurance is available where the damage risk is not acceptable to the client. Seismic Induced Landslide Earthquake-induced landslide zones were delineated by the State of California using criteria adopted by the California State Mining and Geology Board. Under those criteria, earthquake- induced landslide zones are areas meeting one or more of the following: 1. Areas known to have experienced earthquake-induced slope failure during historic earthquakes. 2. Areas identified as having past landslide movement, including both landslide deposits and source areas. 3. Areas where CDMG's analyses of geologic and geotechnical data indicate that the geologic materials are susceptible to earthquake-induced slope failure. Based on the Seismic Hazard Zone Map published by the State of California, Newport Beach Quadrangle, appended as Figure 3, the site is not mapped as being in an area subject to potential seismic induced landslides. Seismic Induced Liquefaction Liquefaction is a seismic phenomenon in which loose, saturated, non-cohesive granular soils exhibit severe reduction in strength and stability when subjected to high-intensity ground shaking. The mechanism by which liquefaction occurs is the progressive increase in excess pore pressure generated by the shaking associated with the seismic event and the tendency for loose non-cohesive soils to consolidate. As the excess pore fluid pressure approaches the in-situ overburden pressure, the soils exhibit behavior similar to a dense fluid with a corresponding significant decrease in shear strength and increase in compressibility. Liquefaction occurs when three general conditions exist: 1) shallow groundwater; 2) low density, non-cohesive sandy soils; and 3) high-intensity ground motion. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 6 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 Seismic Hazard Zone Maps published by the State of California have been prepared to indicate areas that have a potential for seismic induced liquefaction hazards. The Seismic Hazard Zone Map for the Newport Beach Quadrangle, appended as Figure 3, shows the site to be mapped as being subject to potential liquefaction hazards. The City of Newport Beach has a policy concerning these areas. The City has assigned certain parameters to existing soil conditions. From ten to thirty feet below ground surface they have assigned the zone to be liquefiable with a seismic settlement of three inches. From thirty to fifty feet below ground surface they have assigned liquefaction and seismic settlement not to be of concern. The client has the option of accepting these conditions and assessing the zone of earth materials from the ground surface to ten feet below the proposed footing bottom for liquefaction and seismic settlement, or ignoring the City conditions and drilling deep exploration for similar assessment. For this project shallow exploration was chosen. A liquefaction assessment for the upper earth materials follows. Liquefaction evaluation for soil zone to ten feet below foundation bottom was based on blow counts from Boring No. 1, a M = 7.2 seismic event from the Newport-Inglewood fault, a maximum ground acceleration of 0.71g, and a conservative groundwater level at 5 feet. Liquefaction analysis, based on these values and field obtained data, is presented in Appendix B. The results indicate that there is liquefaction potential for the subject site. Earthquake-Induced Settlements Earthquake-induced settlements result from densification of non-cohesive granular soils which occur as a result of reduction in volume during or after an earthquake event. The magnitude of settlement that results from the occurrence of liquefaction is typically greater than the settlement that results solely from densification during strong ground shaking in the absence ofliquefaction. It is understanding that the current City policy, has assigned a seismic settlement potential of three inches for soils depths of ten to thirty feet and no additional analysis of seismic settlement for this level should be required. The seismically induced settlement for the at-grade structure was evaluated based on the "Evaluation of Settlement in Sands due to Earthquake Shaking'' by Kahji Tokimatsu and H. Bolton Seed, dated August 1987. The analysis was limited to ten feet below the footing bottom. The result, based on the SPT N-values in Boring No. 1 and shown in Appendix C, indicates that the estimated settlement (including dry and saturated sands) is 0.59 inch. According to new City policy, the City's shallow mitigation method may be used since the seismic settlement is less than one inch to a depth of ten feet below proposed foundations. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 7 Geotechnical Engineering Investigation Lateral Spreading w. 0. 582819-01 October 29. 2019 The occurrence of liquefaction may cause lateral spreading. Lateral spreading is a phenomenon in which lateral displacement can occur on the ground surface due to movement of non-liquefied soils along zones of liquefied soils. For lateral spreading to occur, the liquefiable zone must be continuous, unconstrained laterally, and free to move along sloping ground toward an unconfined area. Our opinion is that the risk of lateral spreading affecting the proposed structure is minimal due to lack of significant sloping ground and lateral distance to a free face. Earthquake-Induced Flooding The failure of dams or other water-retaining structures as a result of earthquakes and strong ground shaking could result in the inundation of adjacent areas. Due to the lack of a major dam or water-retaining structure located near the site, the potential of earthquake-induced flooding affecting the site is considered not to be present. Seiches Seiches are large waves generated in enclosed bodies of water in response to ground shaking. Based on the lack of nearby enclosed bodies of water the risk from a seiche event is not present. Tsunami Run-up Tsunamis are waves generated in large bodies of water as a result of change of seafloor topography caused by tectonic displacement. Based on the City of Newport Beach "Potential Tsunami Runup Inundation Caused by a Submarine Landslide" map, the subject site is situated in the zone for potential tsunami run-up as shown on Plate 5. For more information about flooding and tsunami run-up hazards, please check the City's website. GEOTECHNICAL DISCUSSION The site is within an area subject to liquefaction and liquefaction induced settlements under certain seismic events. Under current CBC codes, City policy, and industry standards residential structures subject to seismic hazards are designed to protect life and safety. Under this design objective the requirements of protecting life and safety could be met but the structure could be damaged. The damage to the structure could range from minimal to being non-functional. The reduction of risk, for the occurrence of structural damage from a seismic event, is generally associated with the structure's foundation system. Typically the use of a conventional foundation system or a mat foundation system has been utilized in the area. Based on analysis presented within this report and City guidelines concerning liquefaction study mitigation measures the proposed structure can be developed utilizing the City's "strengthened slab on grade foundation system" for support. This type of foundation system, also referred to as a COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 8 Geotechnical Engineering Investigation w. 0. 582819-01 October 29. 2019 conventional foundation system, is a minimum design. As the minimum design, this foundation system has the highest risk for occurrence of structural damage to the residence. The minimum geotechnical requirements for a conventional foundation system are as follows: (1) the structure shall be placed on a mat of compacted fill soil, (2) bottom of all footings shall be 24 inches below grade, (3) foundations shall be continuous or tied together with grade beams, (4) foundations shall be reinforced with a minimum of four #5 bars, two top and two bottom, (5) concrete slabs shall be a minimum of five inch actual thickness with #4 bars at 12 inches on center each way, and (6) footings shall be dowelled into slabs with #4 bars at 24 inches on center. Additional reinforcement maybe required if the structural engineer's design is more stringent. An alternate foundation system typically utilized is a structural mat foundation, which is more rigid than a conventional foundation system, and should be more effective in reducing the risk of structural damage to a structure during a seismic event. Where a mat slab foundation is planned, the slab should be at least twelve inches thick with perimeter footing a minimum of 24 inches below the lowest adjacent grade. Reinforcement shall be determined by the structural engineer. If the risk associated with either of these foundation systems is not acceptable to the client, the client has the option of utilizing more stringent designs that could decrease the risk of damage to the structure to a level they perceive as acceptable. Some of these designs could consist of soil modifications, grout densification, stone columns, piles placed below liquefiable soils, and other methods. Additional geotechnical exploration and or analysis would be required to provide geotechnical design recommendation for these mitigation measures, and would be at the request of the client under separate contract. Grading will be required for support of new foundations as stated within this report. Development of the site as proposed is considered feasible from a soils engineering standpoint, provided that the recommendations stated herein are incorporated in the design and are implemented in the field. The proposed grading and or construction will not have an adverse effect on adjacent property or vice versa, provided site work is performed in accordance with the guidelines of project geotechnical reports, approved plans, applicable codes, industry standards, City inspections, and required geotechnical observation and testing. The following recommendations are subject to change based on review of final foundation and grading plans. PROPOSED GRADING Grading plans were not available at the time this report was prepared. It is anticipated that grading will consist mainly of overexcavation and recompaction for uniform support of the foundations and slabs. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 9 Geotechnical Engineering Investigation GENERAL GRADING NOTES w. 0. 582819-01 October 29, 2019 All existing structures shall be demolished and all vegetation and debris shall be stripped and hauled from the site. The entire grading operation shall be done in accordance with the attached "Specifications for Grading". Any import fill materials to the site shall not have an expansion index greater than 20, and shall be tested and approved by our laboratory. Samples must be submitted 48 hours prior to import. Grading and/or foundation recommendations are subject to modification upon review of final plans by the Geotechnical Engineer. Please submit plans to COAST GEOTECHNICAL, Inc. when available. GRADING RECOMMENDATIONS Removal and recompaction of existing earth materials will be required to provide adequate support for foundations and site improvements. Earthwork for foundation support shall include the entire building pad and shall extend a minimum of three feet outside exterior footing lines. Based on in place densities and consolidation tests, soils found at a depth three feet below existing grade and deeper have adequate geotechnical properties to provide adequate support of proposed fills and the structure; as such, removals to a depth of three feet below existing grade or to one foot below proposed footing bottoms, whichever is greater, are anticipated; however, field observations made at the time of grading shall determine final removal limits. To provide adequate support along property lines excavations shall be sloped at a 1:1 (H:V) gradient from property line down to the excavation bottom. As fill soils are placed the grading contractor shall bench into the 1: 1 construction cut to final grade. Temporary excavations along property lines are shown on Plate 4. During earthwork operations, a representative of COAST GEOTECHNICAL, INC. shall be present to verify compliance with these recommendations. Subsequent to approval of the excavation bottom, the area shall be scarified six inches, moisture conditioned as needed, and compacted to a minimum of 90% relative compaction. Fill soils shall be placed in six to eight inch loose lifts, moisture conditioned as needed, and compacted to a minimum of 90% relative compaction. This process shall be utilized to finish grade. Due to the caving nature of the on-site sands, it is highly recommended that the upper two feet of fill be mixed with Portland cement to mitigate the potential for caving of the foundation excavations. Grading for hardscape areas shall consist of removal and recompaction of loose surficial soils. Removal depths are estimated at one to two feet. Earthwork shall be performed in accordance with previously specified methods. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 10 Geotechnical Engineering Investigation FOUNDATIONS -RESIDENCE w. 0. 582819-01 October 29, 2019 The proposed structures shall be supported by a mat foundation or a conventional foundation system. Conventional foundations shall utilize spread footings and/or isolated pad footings placed a minimum depth of 24 inches below lowest adjacent grade utilizing an allowable bearing value of 1,800 pounds per square foot. This value is for dead plus live load and may be increased 1/3 for total including seismic and wind loads where allowed by code. The structural engineer's reinforcing requirements should be followed if more stringent. Calculations are provided on Plate G. Where isolated pads are utilized, they shall be tied in two directions into adjacent foundations with grade beams. The minimum width of footings shall be 12-inches for single story structures, 15-inches for two-story, and 18-inches for three-story. Footing excavations shall be observed by a representative of COAST GEOTECHNICAL, INC., prior to placement of steel or concrete to verify competent soil conditions. If unacceptable soil conditions are exposed mitigation will be recommended. Geotechnical recommendations for foundation reinforcement are given under the liquefaction section of this report. If a mat slab design is utilized, the structural engineer should design the thickness and reinforcement requirements for the mat foundation for the building based on the anticipated loading conditions. The mat foundation slab should be at least twelve inches thick, with perimeter footings a minimum of 24 inches below the lowest adjacent grade. A modulus of sub grade reaction of 100 pci may be used in the design of the mat foundation. Reinforcement shall be determined by the structural engineer. Calculations for the subgrade reaction are provided on Plate I. Alternate foundations and or additional ground modification techniques, for support of the structure, can be addressed upon request of the project manager. All foundation plans are subject to review and approval of the soils engineer. All foundation bottoms shall be observed and approved by COAST GEOTECHNICAL, Inc. prior to placement of the capillary break. FOUNDATIONS FOR SECONDARY STRUCTURES Site improvements such as free standing retaining walls, site walls, and those structures approved by the geotechnical engineer may be supported by continuous footings or isolated pads bearing in competent fill at least 24 inches below lowest adjacent grade may utilize an allowable bearing value of 1,500 psf. This value is for dead plus live load and may be increased by 1/3 for total including seismic and wind loads where allowed by code. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 11 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 Isolated pads shall be tied into adjacent foundations with designed grade beams in at least two directions. Minimum geotechnical reinforcement of foundations shall be four #5 bars, two top and two bottom. Structural design may require additional reinforcement. LATERAL DESIGN Lateral restraint at the base of footings and on slabs may be assumed to be the product of the dead load and a coefficient of friction of 0.35. Passive pressure on the face of footings may also be used to resist lateral forces. A passive pressure of zero at the surface of finished grade, increasing at the rate of 300 pounds per square foot of depth to a maximum value of 3,000 pounds per square foot, may be used for compacted fill at this site. Calculations are provided on Plate H. If passive pressure and friction are combined when evaluating the lateral resistance, then the value of the passive pressure should be limited to 2/3 of the values given above. FLOOR SLABS Slab on grades shall be designed in accordance with 2016 CBC codes. Site soils are non plastic. Minimum geotechnical recommendations for slab design are five inches actual thickness with #4 bars at 12 inches on center each way. Slabs shall be tied into perimeter foundations with #4 bars at 24 inch centers. Structural design may require additional reinforcement and slab thickness. Sub grade soils shall exhibit a minimum of 90% relative compaction to the depth determined by the geotechnical engineer. The soil should be kept moist prior to casting the slab. However, if the soils at grade become disturbed during construction, they should be brought to approximately optimum moisture content and rolled to a firm, unyielding condition prior to placing concrete. COAST GEOTECHNICAL, Inc. to verify adequacy of subgrade soils prior to placement of capillary break or vapor barrier. Section 4.505.2.1 of the California Green Code requires the use of a capillary break between the slab subgrade and vapor barrier. The capillary break material shall comply with the requirements of the local jurisdiction and shall be a minimum of four inches in thickness. Geotechnically coarse clean sand is acceptable; however, some localities require the use of four inches of gravel (1/2-inch or larger clean aggregate). If gravels are used, a heavy filter fabric (Mirafi 140N) shall be placed over the gravels prior to placement of the recommended vapor barrier to minimize puncturing of the vapor barrier. Additionally, a vibratory plate should be used over the gravels prior to placement of the recommended filter fabric to smooth out any sharp protuberances and consolidate the gravels. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 12 Geotechnical Engineering Investigation w. 0. 582819-01 October 29. 2019 Slab areas should be underlain by a vapor retarder consisting of an engineered plastic film (as described by ASTM:E-1745). In areas where a moisture sensitive floor covering will be used and/or where moisture infiltration is not desirable, a vapor barrier with a permeance of less than O.Olperms (consistent with ACI 302.2R-06) such as 15 mil. Stego Wrap Vapor Barrier, or equivalent, should be considered, and a qualified water proofing specialist should be consulted. The vapor barrier should be underlain by the above described capillary break materials and filter cloth. The capillary break materials should be compacted to a uniform condition prior to placement of the recommended filter cloth and vapor barrier. The vapor barrier should be properly lapped and sealed. SEISMIC DESIGN Based on the 2016 CBC the following seismic design parameters are provided. These seismic design values were determined utilizing latitude 33.61384 and longitude -117.90881 and calculations from the SEAOC/OSHPD Seismic Design Tool Application. A printout of the data is appended. • Site Class = D • Mapped 0.2 Second Spectral Response Acceleration, Ss = 1. 720g • Mapped One Second Spectral Response Acceleration S1 = 0.635g • Site Coefficient from Table 1613A.3.3(1), Fa= 1.0 • Site Coefficient from Table 1613A.3.3(2), Fv = 1.5 • Maximum Design Spectral Response Acceleration for short period, SMs = 1. 720g • Maximum Design Spectral Response Acceleration for one-second period, SM 1 = 0.952g • 5% Design Spectral Response Acceleration for short period, SDs = 1.147g • 5% Design Spectral Response Acceleration for one-second period, Sm = 0.635g SETTLEMENT The maximum total post-construction settlement is anticipated to be on the order of 1/2 inch. Differential settlements are expected to be less than 1/2 inch, measured between adjacent structural elements over a distance of 40 feet. Seismic induced settlements are addressed under previous sections. SUBSIDENCE & SHRINKAGE Subsidence over the site is anticipated to be negligible. Shrinkage of reworked materials should be in the range of 5% to 10%. EXPANSIVE SOILS Results of expansion tests indicate that the near surface soils have a very low expansion potential. UTILITY LINE BACKFILLS All utility line backfills, both interior and exterior, shall be compacted to a m1mmum of 90% relative compaction and shall require testing at a maximum of two-foot vertical intervals. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 13 Geotecbnical Engineering Investigation w. 0. 582819-01 October 29. 2019 Utility lines shall be placed at appropriate depths. Shallow pipes can be damaged by the forces imposed by compacting backfill soils. If shallow pipes are not capable of withstanding the forces of backfill compaction, slurry backfill will be recommended. HARDSCAPE AND SLABS Hardscape and slab sub grade areas shall exhibit a minimum of 90% relative compaction to a depth of at least one foot. Deeper removal and recompaction may be required if unacceptable conditions are encountered. These areas require testing just prior to placing concrete. Hardscape shall be at least four inches thick and reinforced with #3 bars on 18 inch centers both ways. CHEMICAL ANALYSIS An on-site soil sample showed a soluble sulfate content of 4 7 ppm, which is a negligible sulfate exposure. Concrete with Type II 2,500 psi may be utilized; however, the saltwater environ may cause damage to exposed concrete and a designed concrete should be considered. DRAINAGE Positive drainage should be planned for the site. Drainage should be directed away from structures via non-erodible conduits to suitable disposal areas. The structure should utilize roof gutters and down spouts tied directly to yard drainage. Pipes used for storm/site water drainage should be stout enough to withstand the force of compaction of the soils above. This force can be considerable, causing some weaker pipes to collapse. Drainage pipes shall have a smooth interior. Pipes with a corrugated interior can cause the buildup of deleterious matter, which can impede or block the flow of site waters and, as such, are not recommended. All storm/site water drainage pipes should be in conformance with the requirements of Table 1102.5 of the California Plumbing Code. Unlined flowerbeds, planters, and lawns should not be constructed against the perimeter of the structure. If such landscaping ( against the perimeter of a structure) is planned, it should be properly drained and lined or provided with an underground moisture barrier. Irrigation should be kept to a minimum. The current CBC recommends five percent slope away from structures for landscape areas within ten feet of the residence. Hardscape areas shall be sloped a minimum of two percent where within ten feet of the residence unless allowed otherwise by the building official. Minimum drainage shall be one percent for hardscape areas and two percent for all other areas. We do not recommend the use of infiltration best management practice (BMP) such as infiltration trenches, bottomless trench drains, infiltration basins, dry wells, permeable pavements or similar systems designed primarily to percolate water into the subsurface soils within three feet of foundations. Due to the physical characteristics of the site earth materials, infiltration of waters into the subsurface earth materials has a risk of adversely affecting below grade structures, building COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 14 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 foundations and slabs, and hardscape improvements. From a geotechnical viewpoint surface drainage should be directed to the street. The WQMP requirement shall be addressed by the Civil Engineer. ENGINEERING CONSULTATION, TESTING & OBSERVATION We will be pleased to provide additional input with respect to foundation design once methods of construction have been determined. Grading, foundation and shoring plans should be reviewed by this office prior to commencement of grading so that appropriate recommendations, if needed, can be made. Areas to receive fill should be observed when unsuitable materials have been removed and prior to placement of fill. Fill should be observed and tested for compaction as it is placed. SUPPLEMENTAL CONSUL TING During construction, a number of reviews by this office are recommended to verify site geotechnical conditions and conformance with the intentions of the recommendations for construction. Although not all possible geotechnical observation and testing services are required. The following site reviews are advised, some of which will probably be required by the City of Newport Beach: • Grading and excavations review for main structures • Foundation excavations • Slab subgrade compaction testing prior to placement of the capillary break or waste slab • Slab steel placement, primary and appurtenant structures • Compaction of utility trench backfill • Hardscape subgrade compaction AGENCY REVIEW All soil, geologic and structural aspects of the proposed development are subject to the review and approval of the governing agency(s). It should be recognized that the governing agency(s) can dictate the manner in which the project proceeds. They could approve or deny any aspect of the proposed improvements and/or could dictate which foundation and grading options are acceptable. Supplemental geotechnical consulting in response to agency requests for additional information could be required and will be charged on a time and materials basis. LIMITATIONS This report presents recommendations pertaining to the subject site based on the assumption that the subsurface conditions do not deviate appreciably from those disclosed by our exploratory excavations. Our recommendations are based on the technical information, our understanding of the proposed construction, and our experience in the geotechnical field. We do not guarantee the performance of the project, only that our engineering work and judgments meet the standard of care COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 15 Geotechnical Engineering Investigation w. 0. 582819-01 October 29, 2019 of our profession at this time. In view of the general conditions in the area, the possibility of different local soil conditions may exist. Any deviation or unexpected condition observed during construction should be brought to the attention of the Geotechnical Engineer. In this way, any supplemental recommendations can be made with a minimum of delay necessary to the project. If the proposed construction will differ from our present understanding of the project, the existing information and possibly new factors may have to be evaluated. Any design changes and the finished plans should be reviewed by the Geotechnical Consultant. Of particular importance would be extending development to new areas, changes in structural loading conditions, postponed development for more than a year, or changes in ownership. This report is issued with the understanding that it is the responsibility of the owner, or of his representative, to ensure that the information and recommendations contained herein are called to the attention of the Architects and Engineers for the project, and incorporated into the plans and that the necessary steps are taken to see that the contractors and subcontractors carry out such recommendations in the field. This report is subject to review by the controlling authorities for this project. We appreciate this opportunity to be of service to you. Respectfully submitted: COAST GEOTECHNICAL, INC. Ming-Tarng Chen RCE 54011 COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 16 Geotechnical Engineering Investigation APPENDIXA w. 0. 582819-01 October 29, 2019 This appendix contains a description of the field investigation, laboratory testing procedures and results, site plan, exploratory logs and expansive soil recommendations. FIELD INVESTIGATION The field investigation was performed on October 10, 2019, consisting of the excavation of a boring by a limited access drilling rig (for Boring No. 1) and a boring by hand auger equipment (for Boring No. 2) at the locations shown on the attached Site Plan, Figure 2. As drilling progressed, personnel from this office visually classified the soils encountered, and secured representative samples for laboratory testing. Description of the soils encountered is presented on the attached Boring Logs. The data presented on this log is a simplification of actual subsurface conditions encountered and applies only at the specific boring locations and the date excavated. It is not warranted to be representative of subsurface conditions at other locations and times. LABORATORY TESTING Field samples were examined in the laboratory and a testing program was then established to develop data for preliminary evaluation of geotechnical conditions. Field moisture and dry densities were calculated for each undisturbed sample. The samples were obtained per ASTM:D-2937 and tested under ASTM:D-2216. Maximum density-optimum moisture relationships were established per ASTM:D-1557 for use in evaluation of in-situ conditions and for future use during grading operations. Direct shear tests were performed in accordance with ASTM:D-3080, on specimens at near saturation under various normal loads. The results of tests are based on an 80% peak strength or ultimate strength, whichever is lower, and are attached as Plates E and F. Expansion tests were performed on typical specimens of earth materials in accordance with the procedures outlined in ASTM D-4829. A consolidation test was performed on a representative sample based on ASTM:D-2435. The consolidation plot is presented on Plate D. COAST GEOTECHNICAL, INC. Mr. and Mrs. Lisenbee 17 Geotechnical Engineering Investigation TEST RESULTS Maximum Density/Optimum Moisture (ASTM:D-1557) Direct Shear (ASTM:D-3080) 1 0 -5 (remolded) 100 31 2 3 50 31 Expansion Index (ASTM:D-4829) Chemical Analysis (USEPA Method 375.4) w. 0. 582819-01 October 29, 2019 COAST GEOTECHNICAL, INC. SPECIFICATIONS FOR GRADING SITE CLEARING All existing vegetation shall be stripped and hauled from the site. PREPARATION After the foundation for the fill has been cleared, plowed or scarified, it shall be disced or bladed until it is 1miform and free from large clods, brought to a proper moisture content and compacted to not less than ninety percent of the maximum dry density in accordance with ASTM:D-1557 (5 layers -25 blows per layer; 10 lb. hammer dropped 18"; 4" diameter mold). MATERIALS On-site materials may be used for fill, or fill materials shall consist of materials approved by the Soils Engineer and may be obtained from the excavation of banks, borrow pits or any other approved source. The materials used should be free of vegetable matter and other deleterious substances and shall not contain rocks or lumps greater than six inches in maximum dimension. PLACING, SPREADING AND COMPACTING FILL MATERIALS The selected fill material shall be placed in layers which, when compacted, shall not exceed six inches in thickness. Each layer shall be spread evenly and shall be thoroughly mixed during the spreading to ensure uniformity of material and moisture of each layer. Where moisture of the fill material is below the limits specified by the Soils Engineer, water shall be added until the moisture content is as required to ensure thorough bonding and thorough compaction. Where moisture content of the fill material is above the limits specified by the Soils Engineer, the fill materials shall be aerated by blading or other satisfactory methods until the moisture content is as specified. After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to not less than 90 percent of the maximum dry density in accordance with ASTM:D-1557 (5 layers -25 blows per layer; 10 lbs. hammer dropped 18 inches; 4" diameter mold) or other density tests which will attain equivalent results. Compaction shall be by sheepfoot roller, multi-wheel pneumatic tire roller, track loader or other types of acceptable rollers. COAST GEOTECHNICAL, INC. SPECIFICATIONS FOR GRADING PAGE2 Rollers shall be of such design that they will be able to compact the fill to the specified density. Rolling shall be accomplished while the fill material is at the specified moisture content. Rolling of each layer shall be continuous over the entire area and the roller shall make sufficient trips to ensure that the desired density has been obtained. The final surface of the lot areas to receive slabs on grade should be rolled to a dense, smooth surface. The outside of all fill slopes shall be compacted by means of sheepfoot rollers or other suitable equipment. Compaction operations shall be continued until the outer nine inches of the slope is at least 90 percent compacted. Compacting of the slopes may be progressively in increments of three feet to five feet of fill height as the fill is brought to grade, or after the fill is brought to its total height. Field density tests shall be made by the Soils Engineer of the compaction of each layer of fill. Density tests shall be made at intervals not to exceed two feet of fill height provided all layers are tested. Where the sheepfoot rollers are used, the soil may be disturbed to a depth of several inches and density readings shall be taken in the compacted material below the disturbed surface. When these readings indicate that the density of any layer of fill or portion there is below the required 90 percent density, the particular layer or portion shall be reworked until the required density has been obtained. The grading specifications should be a part of the project specifications. The Soil Engineer shall review the grading plans prior to grading. INSPECTION The Soil Engineer shall provide continuous supervision of the site clearing and grading operation so that he can verify the grading was done in accordance with the accepted plans and specifications. SEASONAL LIMITATIONS No fill material shall be placed, spread or rolled during unfavorable weather conditions. When heavy rains interrupt work, fill operations shall not be resumed until the field tests by the Soils Engineer indicate the moisture content and density of the fill are as previously specified. EXPANSIVE SOIL CONDITIONS Whenever expansive soil conditions are encountered, the moisture content of the fill or recompacted soil shall be as recommended in the expansive soil recommendations included herewith. NEWPORT BEACH QUADRANGLE CALIFORNIA -ORANGE CO. 7.5 MINUTE SERIES (TOPOGRAPHIC) SITE VICINITY MAP Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGIC SURVEY Work Order 582819 Plate No. 1 COAST GEOTECHNICAL, INC. \ \ SITE PLAN Scale: 1" ~ 16' LOT27 'u'OO&©'u' OO@o 'O 'O @~ ~D[ij]D 'J'/@/'JJ® Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California (35.12) ~ I Work Order 582819 Plate No. 2 COAST GEOTECHNICAL, INC. . I. ,,. . C .¥1 • I ~1 ·1 4 1: <1 "' "<1 • -c::: SEISMIC HAZARD ZONES MAP /\ STATE OF CALIFORNIA SEISMIC HAZARDS ZONES ;Delineated In compliance with Chapter 7 .8, Diwian 2 of the Callfornla PubUc Resources Code . -(Smsm/< ~--.. . NEWPORT B~CH QUADRANGLE OFFICIAL MAP Liquefactjon Zone Released: April 7, 1997 Landslide Zone· Released: April 15, 1998 45 39 Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California MAP EXPLANATION Zones of Required Investigation: Liquefaction. . Areas where hlstorlc occurrence of liquefaction, or locel geological, geote<;hnlcel.and groundwater conditions indlcate·a potential for permanent 9.round disp/acements such the! mitigation as defined In Public Resources Code SecHon 2693(c) would be required. ' E,arthquaka~lnduced Landslides Areas where previous occurrence of landslide movenierit, or local topographic, geologlcal, geotechnlcel and subsurface water conditlcins indicate a potential for permanent ground dlsplacements such that mltigalion as defined In Public Resources Coda SacHon 2693(c) would be required. Work Order 582819 Plate No. 3 COAST GEOTECHNICAL, INC. TEMPORARY EXCAVATION ALONG PROPERTY LINES BUILDING FACE -- F.F. NEW ~ FOOTING__-· (24") all / /, // / V' SCALE: 1":::: 2' WALL/PL Y.Topof / Slope /I / // l~EMPORARY .f-----} SLOPE /1 / // : ~ BENCHING 7 ---___ .( ______ :, ~ 1: 1 PROJECTION OVER-EXCAVATION This plate is not a representation of actual site conditions. It is a general representation of typical conditions and intended for the illustration of geotechnical data only. The indicated scale is approximate, and to be used for rough measurement only. Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate No. 4 COAST GEOTECHNICAL, INC. POTENTIAL TSUNAMI RUNUP INUNDATION CAUSED BY A SUBMARINE LANDSLIDE SITE 6.ase M.ap: uses Topo~r.aphic Map from Surc!MAPS RASTER Source: City of N::wpo rt 6ea: h, 2007 b.aied on un published re se.arc h by J. C. 60 rrc: ro and others at Un ivers ity of So ut he rn Cal ifo rn i.a NOTES: ihh; map r.ii inmnd,;dkirz,;:n,;:r.a.l la.nd u5.: pliiLnninz only. lnformiiil.tiononthEii map is; not !iitifid;:rt to =:iv,;: z iiL s;u.l:::Jstittm for d;;t;a.ik:d :-p:i bzic: irr.,-a;st ig,;a.tk:a rm of individua.l d.;; .. l'IQr dOi!Si its.a.tig'/thr;:Q'l;lluation ri.t:1uii;:m,;:rt!iiR kirth in ~1.:i:i;ic ha.za.rd r,;:zubtions. Buth Ca:. rr.;u b.nl:5 I rt,;;rml: ional (El:'.:~ miiLb.s no r,;pl'QSQntatio ll5i or ,.,y;a.ria.ntt;S .... d inz th;: .z.o:u liiilCY t:J t h!ii!: diiil.tiil. from wh ic:h thz,;: rmp!ii ',l,'l;:r,;: d.;:ff/1.:d. EC I 5ihall nd: b;: Ii.a.bk!: und,;:r iil.ny d ,::u Mliiita.no;;s; for a.nyd ii.:.d:,. in.di 11.:d:,. s;p;:,::iiiLI,. inddanta.1.. or a::in~ur;:Jt ia.l da.m:a.z;:s; wth r,;s,p;,:t toa.nyda.im byany is;:rorthirdpatyon ao::ou11:of.,eira.ris;inz f1>m. thQ u,oofthi, ""llj Project Num b::r: 2706 Date: 2006 Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California ....... -.. Seale: 1 :60,000 • .. -'..,_..,_""'"""""o,.5 _.._.. ..... ....,1 ·5 Miles EXPLANATION Area that would be inundated bya tsunami generated bya submarine landslide offshore of Newport Beach (areas at or lower than 3 2 foot elevation Newport Beach City Boundary -._ Sphere of Influence Work Order 582819 Plate No. 5 COAST GEOTECHNICAL, INC. UNIFIED SOIL CLASSIFICATION AND KEY TO BORING LOGS UNITED SOIL CLASSIFICATION SYSTEM (ASTM D-2487) PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS GW WELL-GRADED GRAVELS, GRAVEL-SAND MIXTURES, LITTLE GRAVEL AND CLEAN GRAVELS OR NO FINES GRAVELLY (LITTLE OR NO SOILS FINES) GP POORLY-GRADED GRAVELS, GRAVEL-SAND MIXTURES, COARSE LITTLE OR NO FINES GRAINED SOILS MORE THAN 50% OF COARSE GRAVELS WITH GM SIL TY GRAVELS, GRAVELS-SAND-SILT MIXTURES FRACTION FINES RETAINED ON (APPRECIABLE N0.4SIEVE AMOUNT OF FINES) GC CLAYEY GRAVELS, GRAVELS-SAND-CLAY MIXTURES SW WELL-GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO SAND AND CLEAN SAND FINES SANDY SOILS (LITTLE OR NO MORE THAN 50% FINES) SP POORLY-GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO OF MATERIAL IS FINES LARGER THAN NO. MORE THAN 50% 200 SIEVE SIZE OF COARSE SAND WITH SM SILTY SANDS, SAND-SILT MIXTURES FRACTION FINES PASSING NO. 4 (APPRECIABLE SIEVE AMOUNT OF FINES) SC CLAYEY SANDS, SAND-CLAY MIXTURES INORGANIC SILTS AND VERY FINE SANDS, ROCK FLOUR, ML SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY FINE GRAINED SILTS AND LIQUID LIMIT INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, SOILS CLAYS LESS THAN 50 CL GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS OL ORGANIC SIL TS AND ORGANIC SIL TY CLAYS OF LOW PLASTICITY MH INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE MORE THAN 50% SAND OR SIL TY SOILS OF MATERIAL IS SILTS AND LIQUID LIMIT SMALLER THAN CLAYS GREATER THAN CH INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS NO. 200 SIEVE 50 SIZE OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SIL TS HIGHLY ORGANIC SOILS PT ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY COARSE GRAINED SOILS FINE GRAINED SOILS CONSISTENCY BLOWS/FT* CONSISTENCY BLOWS/FT* VERY LOOSE 0-4 VERY SOFT 0-2 LOOSE 4 -10 SOFT 2-4 MEDIUM DENSE 10-30 FIRM 4-8 DENSE 30-50 STIFF 8-15 VERY DENSE OVER50 VERY STIFF 15 -30 HARD OVER30 * BLOWS/FT FOR A 140-POUND HAMMER FALLING 30 INCHES TO DRIVE A 2 INCH O.D., 1-3/8 INCH I.D. SPLIT SPOON SAMPLER (STANDARD PENETRATION TEST) KEY TO SAMPLE TYPE: U = UNDISTURBED SAMPLE B = BULK S = SPT SAMPLE COAST GEOTECHNICAL, INC. COAST GEOTECHNICAL, INC. (Text Supercedes) PLATEA 12" 12" 12" 15" 15" 15" 15" 15" 15" 15" 18" 18" 18" 18" 18" 24" 24" 24" 24" 30" 24" 24" 24" 24" 36" 24" 24" 24" 24" 30" 24" 24" 24" 24" 36" 4 #5 Bars 4 #5 Bars 4 #5 Bars 4 #5 Bars 4 #5 Bars 2 Top 2 Top 2 Top 2 Top 2 Top 2Bottom 2Bottom 2 Bottom 2Bottom 2Bottom 5" Actual 5" Actual 5" Actual 5" Actual 5" Actual #4 Bars on #4 Bars on #4 Bars on #4 Bars on #4 Bars on 12" 12" 12" 12" 12" Centers Both Centers Both Centers Both Centers Both Centers Both Ways Ways Ways Ways Ways 15 mil 15 mil 15 mil 15 mil 15 mil Membrane Membrane Membrane Membrane Membrane #4 Bars on #4 Bars on #4 Bars on #4 Bars on #4Bars on 12" 12" 12" 12" 12" Centers Both Centers Both Centers Both Center Both Center Both Ways Ways Ways Ways Ways Same as Adj. Same as Adj. Same as Adj. Same as Adj. Same as Adj. Ext. Ftg. Ext. Ftg. Ext. Ftg. Ext. Ftg. Ext. Ftg. 4" Clean 4" Clean 4" Clean 4" Clean 4" Clean Aggregate Aggregate Aggregate Aggregate Aggregate Above Opt. 110% of Opt 130% of Opt 130% of Opt To M/Cto MIC to Depth MIC to Depth Depth of Ftg. Depth Footing Footing (No Testing) Footing 1. Basement slabs shall have a minimum thickness of six inches. 2. Floor slab shall be constructed over a 15 mil plastic membrane. The membrane shall be properly lapped, sealed and in contact with the slab bottom. 3. Aggregate should be Yz-inch or larger. Date: Q) I-.2 ~~ z 28 14 10 21 36 SUMMARY OF BORING NO. 1 10/10/2019 Elevation: E.G. -C CJ) Q) Q) ~ C Q) ·-a. u. 3 2 5 10 12 Q) +..: CJ) ........ Q) +..: :5 s ci u. -t5 ~ E ..c ·o o Ctl -c.. ~~ Cl) Q) 0 -u B 4.3 5 7.8 23.7 22.8 10 22.3 15 Description L. 0 0 C) FILL: SAND ---silty, fine-grained, damp, with roots Brown NATIVE: SAND ---clean, fine to medium-grained, Light Gray damp Tan to Tan SAND ---clean, fine-grained, moist Light Gray SAND ---clean, fine-grained, wet Dark Gray SAND ---silty, fine to medium-grained, wet Gray to Dark Gray SAND ---silty, fine to medium-grained, wet Gray to Dark Gray End of boring at 12.5 feet Groundwater at 7 feet Sands are subject to caving ~ C Q) -CJ) "cii C 0 C) Loose Medium Dense Medium Dense Medium Dense Medium Dense Dense Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate B COAST GEOTECHNICAL, INC. SUMMARY OF BORING NO. 2 Date: 10/10/2019 Elevation: E.G. >, -en ->, -Q) ....: Q) ....: (.) "iii C c-=is ci LL .... Q) Q) t; ........ 0 -->, E .c Description 0 en Cl a.. en ,._ ·a o ro -0 "iii ~-U) 0. C 2: '?f!. Q) 0 Cl ........ Cl 0 U B FILL: SAND ---silty, fine to medium-grained, dry Brown Loose - 2 NATIVE: SAND ---clean, fine to medium-grained, Tan to Gray Medium damp Tan Dense - 100.9 1.5 4 - - 101.7 6.1 SAND ---clean, fine to medium-grained, damp to Light Gray Medium moist Dense 6 - - 101.4 20.9 SAND ---clean, fine to medium-grained, very Gray to Dark Medium moist to wet Gray Dense 8 End of boring at 8 feet Groundwater at 7.5 feet Sands are subject to caving - 10- - Geotechnical Engineering Investigation Work Order 582819 2701 Circle Drive Newport Beach, California Plate C COAST GEOTECHNICAL, INC. CONSOLIDATION TEST RESULTS [ Boring No. 2 @ 3.0 Feet ) Pressure (Kips Per Square Foot) 0.1 1 10 0.00 I"\.... --, -- 1.00 -. .......... ........... ......... ... 11. 2.00 --........ r--' ----.., --' -_, 3.00 -..... C: Cl) CJ 4.00 ... Cl) D. -C: 0 5.00 .:; ca "C 0 V, 6.00 C: 0 (.) 7.00 8.00 9.00 10.00 0 Test Specimen at In-Situ Moisture • Test Specimen Submerged Geotechnical Engineering Investigation Work Order 582819 2701 Circle Drive Newport Beach, California Plate No. D COAST GEOTECHNICAL, INC. SHEAR TEST RESULT [ Boring No.1 @ 0 to 5 Feet (Re molded to 90%) ) 5 4 0 1 2 3 4 5 Confining Pressure (kips/sq. ft.) Remolded soil samples were tested at saturated conditions. The sample had a dry density of 101.4 lbs./cu.ft. and a moisture content of 24.3 %. Cohesion = 100 psf Friction Angle= 31 degrees Based on 80% peak strength or ultimate strength, whichever is lower Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate No. E COAST GEOTECHNICAL, INC. SHEAR TEST RESULT ( Boring No. 2 @ 3.0 feet l 5 4 ~ ~ 2 -Cl) 0 1 2 3 4 5 Confining Pressure (kips/sq. ft.) Native soil samples were tested at saturated conditions. The sample had a dry density of 100.9 lbs./cu.ft. and a moisture content of 24.6 %. Cohesion = 50 psf Friction Angle = 31 degrees Based on 80% peak strength or ultimate strength, whichever is lower Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate No. F COAST GEOTECHNICAL, INC. ALLOWABLE BEARING CAPACITY Bearing Capacity Calculations are based on "Terzaghi's Bearing Capacity Theory" Bearing Material: Compacted Fill Properties: Wet Density (y) = 110 pcf Cohesion (C) = 100 psf Angle of Friction (<P) = 31 degrees Footing Depth (D) = 2 feet Footing Width (B) = 1.3 feet Factor of Safety = 3.0 Calculations -Ultimate Bearing Capacity from Table 3.1 on page 127 of "Foundation Engineering Handbook", 1975 Ne= 32.67 Nq = 20.63 Ny = 25.99 Ou = 1.3 C Ne+ y D Nq + 0.4 y B Ny (Square Footing) = 1.3 * 100 * 32.67 + 110 * 2 * 20.63 + 0.4 * 110 * 1.25 * 25.99 = 4247 + 4538 + 1429 = 10214 psf Allowable Bearing Capacity for Square Footing Oa11= Ouf F.S. = Use 1800 psf 3404 psf Ou = 1.0 C Ne+ y D Nq + 0.5 y B Ny (Continuous Footing) = 1.0 * 100 * 32.67 + 110 * 2 * 20.63 + 0.5 * 110 * 1.25 * 25.99 = 3267 + 4538 + 1786 = 9591 psf Allowable Bearing Capacity for Continuous Footing Oa11= Ouf F.S. = Use 1800 psf 3197 psf Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate G COAST GEOTECHNICAL, INC. LATERAL EARTH PRESSURE CALCULATIONS Retaining structures such as retaining walls, basement walls, and bulk-heads are commonly used in foundation engineering, and they support almost vertical slopes of earth masses. Proper design and construction of these structures require a through knowledge of the lateral forces acting between the retaining structures and the soil masses being retained. These lateral forces are due to lateral earth pressure. Properties of earth material: Compacted fill Wet Density (y) Cohesion (C) = = 110 pcf 100 psf Angle of Friction(¢) = 31 degrees Coefficient of Friction = tan <I> Therefore, Coefficient of Friction = tan <I> = tan¢ = 0.601 Assumed H = 2 feet Use 0.35 Pp= 0.5 y H2 tan 2 ( 45° + ¢ / 2) + 2 C H tan ( 45° + ¢ / 2) = 0.5*110*4*3.122+2*100*2*1.767 = 687 + 707 = 1394 lbs /LF 1/2 EFP H2 = 1394 EFP = 697 psf / LF EFP: passive pressure Allowable Passive Pressure= 300 psf / LF ( with F.S. = 2.32) Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate H COAST GEOTECHNICAL, INC. CALCULATION OF SUBGRADE REACTION Subgrade reaction calculations are based on "Foundation Analysis and Design" Fourth Edition, by Joseph E. Bowles. Ks = 24 quit (for L.lH = 1/2 inch) Where: Ks = subgrade reaction in k / ft3 quit = ultimate bearing capacity For quit = 9.6 ksf (from bearing capacity calculations) Ks = 24 * 9.59 k / ft3 = 230.2* 1000 I ( 12 * 12 * 12) lb/ in 3 = 133.2 lb/ in 3 Use 100 pound per cubic inch Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California COAST GEOTECHNICAL Work Order 582819 Plate No. I APPENDIXB Liquefaction Analysis by SPT Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California COAST GEOTECHNICAL, INC. lp~~~h :/(ff[ 3 5 7 9 11 LIQUEFACTION ANALYSIS BY SPT FOR BORING NO. 1 CN = (Pa/ ao' )112 < 2, Pa= 2089 psf (N1)50 = Nm CN CE Cs CR Cs CSR= Tavl a 0' = 0.65 ( a 0 I a 0') rd ( amaxl g) !lll!lllll 11!1~illl~ 16 "-"L_: ~_:_:~ ·- 315.0 315.0 28 2.00 I 1.00 I 1.05 I o.75 I 1.20 525.0 525.0 14 1.99 I 1.00 I 1.05 I 0.75 I 1.20 775.0 650.2 10 1.79 I 1.00 I 1.05 I 0.75 I 1.20 1025.0 I 775.4 21 1.64 I 1.00 I 1.05 I o.75 I 1.20 1275.0 I 900.6 36 1.52 I 1.00 I 1.05 I o.75 I 1.20 i~N~Je8:: ltilqii\is.fft 52.9 26.4 16.9 32.6 51.8 .r] ll@~~t~ 1rfl]/i ~~~~~ l~~~IRffl!ita 0.99 I 0.46 3 o.60 I 1.15 I 0.69 0.99 I 0.46 2 0.31 I 1.15 I 0.36 0.99 I 0.54 5 0.19 I 1.15 I 0.22 0.98 I 0.60 10 0.60 I 1.15 I o.69 0.98 I 0.64 12 0.60 I 1.15 I o.69 Note: 1. Moist unit weight of 105 pcf, saturated unit weight of 125 pcf, and groundwater at 5 feet 2. Magnitude of 7.2 and peak ground acceleration of 0.71 g 3. According to Figure 7.1, soil layers having (N 1 )60 higher than 30 are not considered liquefiable. Geotechnical Engineering Investigation I Work Order 582819 2701 Circle Drive Newport Beach, California Plate M COAST GEOTECHNICAL, INC. ,ts. ·-·-···=-(::=:.-.·. 1.51 0.78 0.40 1.15 1.08 QJ QJ .... .=: a. <I.I a ( "t" max )d rd=--- (Tmaxlr 0 0 I O 2 0.3 0.4 0.5 0.6 0.7 0.8 1.0 0.9 a-;._-~· _ ___::..;.·--~--~---;-----;--'"'--,---,--~---i I 10 l I 20 I --I 30 40 I t I I I I I I I ! I 50 I I 60 I 1--i-T--,--1--1--' I I ;ve,aqe values"":\.nl !-f- I I I I I I I I I I Range for aifferent soil profiles I I I I l I I . I I ,.., , I, 1 \ '/ ·· I • \ I ' i I I I. FIG. 1 -RANGE OF VALUES OF rd FOR DIFFERENT SOIL PROFILES Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Liquefaction Hazards in California Table 5.2. Corrections to Field SPT N-Values (modified from Youd and Idriss, 1997) ·Factor Equipinent Variable Term Overburden Pressure CN Energy Ratio Safety Hammer CB Donut Hammer Automatic Trip Hammer Borehole Diameter 65 mm to 115 mm c. 150mm 200mm Rod Length** 3mto4m c. 4mto6m 6mto 10m 10m to 30m >30m Sampling Method Standard Sampler Cs Sampler without liners * The Implementation Committee recommends using a minimum of 0.4. ** Actual total rod length, not depth below ground surface 12 Correction (P ./ cr 'v. )°"; 0.4.::;;CN.::;;2 * 0.60 to 1.17 0.45 to 1.00 0.9 to 1.6 1.0 1.05 1.15 0.75 0.85 0.95 1.0 <1.0 1.0 1.2 Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Liquefaction Hazards in California 0.6-----...------37~---------------- Percent Fines = 35 15 ~5 I I 0.5~-----1-------44,--i-----,i------1------~ I I I I I I I I I I I I I I I I I I I I I i 0.41------------~...-20-,.:....' ----'-, -+------------ '-,) I I -4-..._. I :> , ~, !-:: I I •31 I I CRR curves for 5,15, and I I I I I I 35 percent fines, respectively Maroinal No Liquefaction Liquefaction Liquefaction Pan -American data • lll Japanese data • Q e Chinese data .a. A Adjustment Recommended By Workshop 0 L_ _ _i.:;=====l---l. ____ .J_ ___ _L ___ ___i 0 10 20 30 40 50 Corrected Blow Count, (N1)60 Figure 7.1. Simplified Base Curve Recommended for Determination of CRR from SPT Data for Moment Magnitude 7.5 Along with Empirical Liquefaction Data (after Youd and Idriss, 1997) 50 Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Liquefaction Hazards in California ~ Cl:l ~ ;..j' .8 ~ 00 Q ·--c-s 0 Cl:l ~ "O ::I ..... ·-Q 00 ~ ~ 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 5.0 Workshop 6.0 7.0 -+-Seed and Idriss, (1982) -Idriss x Arnbraseys(1985) ¢ Arango (1996) + Arango (1996) _.,_ Andrus and Stokoe • Youd and Noble, PL<20% I::. Youd and Noble, PL<32% .A. Youd and Noble, PL<50% 8.0 9.0 Earthquake Magnitude, Mw Figure 7.2. Magnitude Scaling Factors Derived by Various Investigators (After Youd and Idriss, 1997) 51 APPENDIXC Calculations of Seismically Induced Settlement Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California COAST GEOTECHNICAL, INC. CALCULATIONS OF SEISMICALLY-INDUCED SETTLEMENT Calculations of seismically-induced settlement for the subject site are performed based on the II Evaluation Of Settlement In Sands Due To Earthquake Shaking II by Kohji Tokimatsu and H. Bolton Seed, dated August 1987. The calculations of the seismically-induced settlement are as follows: 1. Calculate the effective overburden pressure at the center of each layer. 2. The SPT N-value needs to be corrected depending on equipment used and a0'. (N1)50 = Nm CN CE Cs CR Cs Where CN = (Pa/ a 0') 112 < 2, Pa= 2089 psf (N1)50 = corrected N value Nm = field N value CN = correction factor depending on effective overburden pressure a0' = effective overburden pressure, in psf 3. Calculate the maximum shear modulus Gmax = 20 (N1)50 1/3 ( ao' ) 112 Gmax = maximum shear modulus, in ksf a0' = effective overburden pressure, in psf 4. From the depth in Figure 1, find the stress reduction coefficient, rd 5. Calculate y eff ( Geff / Gmax ) Yeff ( Geff / Gmax) = 0.65 amax a0 rd/ ( g Gmax) amax = 0.71 g and M = 7.2 ( for the subject site) Yeff = effective shear strain induced by earthquake shaking Geff = effective shear modulus at induced strain level (cont'd) Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate N1 COAST GEOTECHNICAL, INC. CALCULATIONS OF SEISMICALLY-INDUCED SETTLEMENT amax = maximum ground surface acceleration a0 = total overburden pressure g = acceleration of gravity 6. From Yeff ( Geff / Gmax) and a0' in Figure 2, find Yeff (cyclic shear strain) 7. From Yeff and (N 1)60 in Figure 3, find sc.M. = 7.5 (volumetric strain due to compaction) 8. Interpolation from Table 1, sc.M. = 7.2 = 0.940 sc.M. = 7.5 9. This settlement caused by combined horizontal motions is about equal to the sum of the settlement caused by the components acting alone. Calculate 2 s c.M. = 7.2 10. Calculate the total settlement Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California Work Order 582819 Plate N2 COAST GEOTECHNICAL, INC. SEISMICALLY INDUCED SETTLEMENT OF DRY SAND FOR BORING NO. 1 :r:d:: :!te~p~~R~~}\ T~# '~~~ii'i' I ~~~ijij' I ~~~~i'.~ :m~~tl~~\' ~1:1111~l~~~ll*~i~~lt i~; /~®\ Ji /t~ I N~Y N1J5d II . ·-=:::::=:::::::::: 2 2.0 4.0 3.0 2.0 I 315 315 28 I 26.4 I 1057 I o.99 I 13.6 *10-5 I 34 *10-5 1 0.026 I 0.024 0.049 0.01 4.0 5.0 4.5 1.0 I 473 473 14 I 16.9 I 1116 I o.99 I 19.4 *10-5 I 62 *10-5 I 0.080 I o.075 0.150 0.02 TOTAL 0.03 Based on : 1. Moist unit weight of 105 pcf, saturated unit weight of 125 pcf, and groundwater at 5 feet 2. Magnitude of 7.2 and peak ground acceleration of 0.71 g 3. Gmax = 20 (N1)50 1/3 ( aa' ) 1/2 4. Yeff ( Geff I Gmax) = 0.65 amax ao rd/ ( g Gmax) Geotechnical Engineering Investigation 2701 Circle Drive Work Order 582819 Newport Beach, California Plate No. N3 COAST GEOTECHNICAL, INC. --" ~ C ·-0 ..... VJ I.. 0 4.) .c. Vl 10 3 ·4 10 -!> 10 i..-..~___.._____...__.__.__... ................. ~~_.....~_.___.._ ............... ......i...J..J..~~--'-..--J ,o-3 ,o-5 ,o-4 raff (Geff/Gma:w.) FIG. ·:z. -PLOT FOR DETERMINATION OF INDUCED STRAIN IN SAND DEPOSITS C • 2 ~10 .... C, 0. u w C 0 u 0 0. E 10 1 0 u 0 - C: 0 "- u, u ... - N 1~40 ~30 :::::10 :::::5 ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' IS Cycles ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' \. .... .... .... ... FIG. 3 -RELATIONSHIP BETWEEN VOLUMETRIC STRAIN, SHEAR STRAIN, AND PENETRATION RESISTANCE FOR DRY SANDS TABLE 1 -INFLUENCE OF EARTHQUA.KE MAGNITUDE ON VOLUMETRIC STRAIN RATIO FOR DRY SANDS Earthquake magnitude (1) 8-1/2 7-1/2 6-3/4 6 5-1/4 Number of representative cycfeS at 0.65 T max (2) 26 15 10 5 2~3 Volumetric strain ratio, Ec.N / Ec,-t1-1s (3) 1.25 1.0 0.85 0.6 0.4 SEISMICALLY INDUCED SETTLEMENT OF SATURATED SOILS FOR BORING NO. 1 ll~j I ~~l~f iII, /l~f ~~t I ,!]~j I \~1~1! I ~i/f jj rnw p <I :;~!,j)(I~ iii~~;~ 111~~~~!1!1 l~~~l!~!! 5.0 6.0 1.0 I 26.4 2 o.oo I 1.00 26.4 0.46 1.15 0.40 1.1 0.13 2 6.0 8.0 2.0 I 16.9 5 o.oo I 1.00 16.9 0.54 1.15 0.47 1.8 0.43 3 8.0 10.0 2.0 I 32.6 10 0.87 I 1.02 34.2 0.60 1.15 0.52 0.0 0.00 4 10.0 12.0 2.0 I 51.8 12 1.55 I 1.03 55.0 0.64 1.15 0.56 0.0 0.00 TOTAL 0.56 Note: 1. Groundwater at 5 feet, magnitude of 7.2, and peak ground acceleration of 0.71 g 2. (N1)50 cs= a + fJ (N1)60 3. For volumetric strain refer to Figure 7.11 Geotechnical Engineering Investigation 2701 Circle Drive Newport Beach, California COAST GEOTECHNICAL Work Order 582819 Plate No. 0 ·\ ... Thomas F. Blake (Fugro-West, Inc., Ventura, Calif., written commun.) approximated the simplified base curve plotted on Figure 2 by the following equation: a + ex + ex 2 + gx 3 CRR 7 5 = ---------- . 1 + bx + dx 2 + fx 3 + hx 4 (4) where CRR7_5 is the cyclic resistance ratio for magnitude 7.5 earthquakes; x = (N1)60 ; a= 0.048; b = -0.1248; c = -0.004721; d = 0.009578; e = 0.0006136; f= -0.0003285; g = -l.673E-05; and h = 3.714E-06. This equation is valid for (N 1)60 less than 30 and may be used in spreadsheets and other analytical techniques to approximate the simplified base curve for engineering calculations. Robertson and Wride (this report) indicate that Equation 4 is not applicable for (N 1)60 less than three, but the general consensus of workshop participants is that the curve defined by Equation 4 should be extended to intersect the intercept at a CRR value of about 0.05. Correlations for Fines Content and Soil Plasticity Another change was the quantification of the fines content correction to better fit the empirical data and to support computations with spreadsheets and other electronic computational aids. In the original development, Seed et al. (1985) found that for a given (N 1)60 , CRR increases with increased fines. content. It is not clear, however, 'whether the CRR increase is because of greater liquefaction resistance or smaller penetration resistance as a consequence of the general increase of compressibility and decrease of permeability with increased fines content. Based on the empirical data available, Seed et al.·developed CRR curves for various fines contents as shown on Figure 2. After a lengthy review by. the workshop participants, consensus was gained that the correction for fines content should be a function of penetration resistance as well as fines content. The participants also agreed that other grain characteristics, such as soil plasticity may affect liquefaction resistance; hence any correlation .based solely on penetration.resistance and fines content should be used with t:ngineering judgement ,and caution. The following equations, developed by I.M. Idriss with assistance from R.B. Seed are recommended for correcting standard penetration resistance determined for silty sands to an equivalent clean sand penetration resistance: (5) where a. and p are coefficients determined from the following equations: a= 0 for FC 5; 5% (6a) a= exp[l.76 -(l 90/FC2)] for 5% < FC < 35% (6b) a.=5.0 forFC ~ 35% (6c) p = 1.0 . for FC 5; 5% (7a) p = [0.99 + (FCu/1000)] for 5% < FC < 35% (7b) p = 1.2 forFC ~ 35% (7c) where FC is the fines content measured from laboratory gradation tests on retrieved soil samples. 7 Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and Mitigating Liquefaction Hazards in California Volumetric Stro in-% 0.5 10 5 4 3 2 0.5 I I 0.4 0.3 0.2 ·0.1 I I I I / J /,0.2 I I I I I I /. //p.1 I I I I I I I ·I I I I I I I / I I '/ I. I I / / I / / / / / / / / / / / / / / / / / / / / / / /// / / // // // '// '// '// :;,'/ ~ 10 20 30 40 50 Figure 7.11. Relationship Between Cyclic Stress Ratio, (N 1)60 and Volumetric Strain for Saturated Clean Sands and Magnitude= 7.5 (After Tokimatsu and Seed, 1987) 60 2701 Circle Dr, Newport Beach, CA 92663, USA Latitude, Longitude: 33.6138374, -117.90881200000001 Date Design Code Reference Document Risk Category 10/17/2019, 1:00:19 PM ASCE7-10 II Site Class Type Ss S1 SMs SM1 Sos So1 Type soc Fa Fv PGA FPGA PGAM TL SsRT SsUH SsD S1RT S1UH S1D PGAd CRs CR1 Value 1.72 0.635 1.72 0.952 1.147 0.635 Value D 1.5 0.71 0.71 8 1.72 1.916 3.296 0.635 0.694 1.121 1.21 0.898 0.915 Description MCER ground motion. (for 0.2 second period) MCER ground motion. (for 1.0s period) Site-modified spectral acceleration value Site-modified spectral acceleration value Numeric seismic design value at 0.2 second SA Numeric seismic design value at 1.0 second SA Description Seismic design category Site amplification factor at 0.2 second Site amplification factor at 1.0 second MCEG peak ground acceleration Site amplification factor at PGA Site modified peak ground acceleration Long-period transition period in seconds Probabilistic risk-targeted ground motion. (0.2 second) D -Stiff Soil Factored uniform-hazard (2% probability of exceedance in 50 years) spectral acceleration Factored deterministic acceleration value. (0.2 second) Probabilistic risk-targeted ground motion. (1.0 second) Factored uniform-hazard (2% probability of exceedance in 50 years) spectral acceleration. Factored deterministic acceleration value. (1.0 second) Factored deterministic acceleration value. (Peak Ground Acceleration) Mapped value of the risk coefficient at short periods Mapped value of the risk coefficient at a period of 1 s OSHPD ~ C1l Cl) MCER Response Spectrum 2.0 1.5 1.0 0.5 0.0 0.0 2.5 5.0 Period, T (sec) -Sa(g) Design Response Spectrum 1.5 1.0 0.5 0.0 0.0 2.5 5.0 Period, T (sec) -Sa(g) 7.5 7.5 DISCLAIMER While the information presented on this website is believed to be correct, SEAOC /OSHPD and its sponsors and contributors assume no responsibility or liability for its accuracy. The material presented in this web application should not be used or relied upon for any specific application without competent examination and verification of its accuracy, suitability and applicability by engineers or other licensed professionals. 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