Geotechnical Investigations & Reports

Grounded in the retrieved California Building Code — click a citation to read the verbatim passage:

• CBC § 1803.1 High relevance — show source text

  SECTION 1803—GEOTECHNICAL INVESTIGATIONS

  1803.1 General. Geotechnical investigations shall be conducted in accordance with Section 1803.2 and reported in accordance with Section 1803.6. Where required by the building official or where geotechnical investigations involve in-situ testing, laboratory testing or engineering calculations, such investigations shall be conducted by a registered design professional. [OSHPD 1R, 2 & 5] The classi- fication, testing and investigation of the soil shall be made under the responsible charge of a California registered geotechnical engineer. All recommendations contained in geotechnical and geohazard reports shall be subject to the approval of the enforcement agency. All reports shall be prepared and signed by a registered geotechnical engineer, certified engineering geologist and a registered geophysicist, where applicable.

  1803.1.1 General and where required for applications listed in Section 1.8.2.1.1 regulated by the Department of Housing and Community Development. [HCD 1] Foundation and soils investigations shall be conducted in conformance with Health and Safety Code Sections 17953 through 17957 as summarized below.

  1803.1.1.1 Preliminary soil report. Each city, county, or city and county shall enact an ordinance which requires a preliminary soil report, prepared by a civil engineer who is registered by the state. The report shall be based upon adequate test borings or excavations, of every subdivision, where a tentative and final map is required pursuant to Section 66426 of the Government Code.

  The preliminary soil report may be waived if the building department of the city, county, or city and county, or other enforce- ment agency charged with the administration and enforcement of the provisions of Section 1803.1.1, shall determine that, due to the knowledge such department has as to the soil qualities of the soil of the subdivision or lot, no preliminary analysis is necessary.

  1803.1.1.2 Soil investigation by lot, necessity, preparation and recommendations. If the preliminary soil report indicates the presence of critically expansive soils or other soil problems which, if not corrected, would lead to structural defects, such ordi- nance shall require a soil investigation of each lot in the subdivision.

  The soil investigation shall be prepared by a civil engineer who is registered in this state. It shall recommend corrective action which is likely to prevent structural damage to each dwelling proposed to be constructed on the expansive soil.

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  SOILS AND FOUNDATIONS

  1803.1.1.3 Approval, building permit conditions, appeal. The building department of each city, county, or city and county, or other enforcement agency charged with the administration and enforcement of the provisions of Section 1803.1.1, shall approve the soil investigation if it determines that the recommended action is likely to prevent structural damage to each dwelling to be constructed. As a condition to the building permit, the ordinance shall require that the approved recommended action be incorpo- rated in the construction of each dwelling. Appeal from such determination shall be to the local appeals board.

• CBC § 1801.1.2 High relevance — show source text

  1801.1.2 Amendments in this chapter. [OSHPD 1R, 2 & 5] OSHPD adopts this chapter as amended.

  1801.1.3 Identification of amendments. [OSHPD 1R, 2 & 5] Office of Statewide Hospital Planning and Development (OSHPD) amendments appear in this chapter preceded with the appropriate acronym, as follows:

  [OSHPD 1R ] – For applications listed in Section 1.10.1.

  [OSHPD 2] – For applications listed in Section 1.10.2.

  [OSHPD 5] – For applications listed in Section 1.10.5.

  SECTION 1802—DESIGN BASIS

  1802.1 General. Allowable bearing pressures, allowable stresses and design formulas provided in this chapter shall be used with the allowable stress design load combinations specified in ASCE 7, Section 2.4 or the alternative allowable stress design load combinations of Section 1605.2. The quality and design of materials used structurally in excavations and foundations shall comply with the requirements specified in Chapters 16, 19, 21, 22 and 23. Excavations and fills shall comply with Chapter 33.

  [HCD 1] For limited-density owner-built rural dwellings, pier foundations, stone masonry footings and foundations, pressure-treated lumber, poles or equivalent foundation materials or designs may be used, provided that the bearing is sufficient for the purpose intended.

  SECTION 1803—GEOTECHNICAL INVESTIGATIONS

  1803.1 General. Geotechnical investigations shall be conducted in accordance with Section 1803.2 and reported in accordance with Section 1803.6. Where required by the building official or where geotechnical investigations involve in-situ testing, laboratory testing or engineering calculations, such investigations shall be conducted by a registered design professional. [OSHPD 1R, 2 & 5] The classi- fication, testing and investigation of the soil shall be made under the responsible charge of a California registered geotechnical engineer. All recommendations contained in geotechnical and geohazard reports shall be subject to the approval of the enforcement agency. All reports shall be prepared and signed by a registered geotechnical engineer, certified engineering geologist and a registered geophysicist, where applicable.

  1803.1.1 General and where required for applications listed in Section 1.8.2.1.1 regulated by the Department of Housing and Community Development. [HCD 1] Foundation and soils investigations shall be conducted in conformance with Health and Safety Code Sections 17953 through 17957 as summarized below.

  1803.1.1.1 Preliminary soil report. Each city, county, or city and county shall enact an ordinance which requires a preliminary soil report, prepared by a civil engineer who is registered by the state. The report shall be based upon adequate test borings or excavations, of every subdivision, where a tentative and final map is required pursuant to Section 66426 of the Government Code.

• CBC § 5.5. High relevance — show source text

  The report shall_ contain the results of the analyses of problem areas identified in the geohazard report. The geotechnical report shall incorporate esti- mates of the characteristics of site ground motion provided in the geohazard report. This geotechnical report shall include, but need not be limited to, the following information:

  1. A plot showing the location of the soil investigations.
  2. A complete record of the soil boring and penetration test logs and soil samples.
  3. A record of the soil profile.
  4. Elevation of the water table, if encountered. Historic high ground water elevations shall be addressed in the report to adequately evaluate liquefaction and settlement potential.
  5. Recommendations for foundation type and design criteria, including but not limited to: bearing capacity of natural or compacted soil; provisions to mitigate the effects of expansive soils; mitigation of the effects of liquefaction, differential settlement and varying soil strength; and the effects of adjacent loads.
  6. Expected total and differential settlement.
  7. Deep foundation information in accordance with Section 1803 A .5.5.
  8. Special design and construction provisions for foundations of structures founded on expansive soils, as necessary.
  9. Compacted fill material properties and testing in accordance with Section 1803 A .5.8.
  10. Controlled low-strength material properties and testing in accordance with Section 1803 A .5.9. 11. The report shall consider the effects of stepped footings addressed in Section 1809A.3. 12. The report shall consider the effects of seismic hazards in accordance with Section 1803A.6 and shall incorporate the associ- ated geohazard report.

  1803A.8 Geotechnical peer review. [DSA-SS and DSA-SS/CC] When alternate foundations designs or ground improvements are employed or where slope stabilization is required, a qualified peer review by a California-licensed geotechnical engineer, in accordance with Section 322 of Part 10, Title 24, CCR, may be required by the enforcement agency. In Section 322 of Part 10, Title 24, CCR, where reference is made to structural or seismic-resisting system, it shall be replaced with geotechnical, foundation or ground improvement, as appropriate.

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  SOILS AND FOUNDATIONS

  SECTION 1804 A —EXCAVATION, GRADING AND FILL

  1804 A .1 Excavation near foundations. Excavation for any purpose shall not reduce vertical or lateral support for any foundation or adjacent foundation without first underpinning or protecting the foundation against detrimental lateral or vertical movement, or both, in accordance with Section 1803 A .5.7.

  1804 A .2 Underpinning. Where underpinning is chosen to provide the protection or support of adjacent structures, the underpinning system shall be designed and installed in accordance with provisions of this chapter and Chapter 33.

  1804 A .2.1 Underpinning sequencing. Underpinning shall be installed in a sequential manner that protects the neighboring structure and the working construction site. The sequence of installation shall be identified in the approved construction documents.

• CBC § 1803A.5.11 High relevance — show source text

  In addition, the most recent version of_ CGS Special Publication 42: Earthquake Fault Zones, A Guide for Government Agencies, Property Owners / Developers, and Geoscience Practitioners for Assessing Fault Rupture Hazards in California, shall be considered for project sites proposed within an Alquist-Priolo Earthquake Fault Zone. The most recent version of CGS Special Publication 117, Guidelines for Evaluating and Mitigating Seismic Hazards in California, shall be considered for project sites proposed within a Seismic Hazard Zone. All conclusions shall be fully supported by satisfactory data and analysis.

  In addition to requirements in Sections 1803A.5.11 and 1803A.5.12, the report shall include, but need not be limited to, the following: 1. Site geology. 2. Evaluation of the known active and potentially active faults, both regional and local. 3. Ground-motion parameters, as required by Sections 1613A and 1617A, and ASCE 7.

  1803A.7 Geotechnical reporting. Where geotechnical investigations are required, a written report of the investigations shall be submitted to the building official by the permit applicant at the time of permit application. The geotechnical report shall provide completed evaluations of the foundation conditions of the site and the potential geologic/seismic hazards affecting the site. The geotechnical report shall include, but shall not be limited to, site-specific evaluations of design criteria related to the nature and extent of foundation materials, groundwater conditions, liquefaction potential, settlement potential and slope stability. The report shall contain the results of the analyses of problem areas identified in the geohazard report. The geotechnical report shall incorporate esti- mates of the characteristics of site ground motion provided in the geohazard report. This geotechnical report shall include, but need not be limited to, the following information:

  1. A plot showing the location of the soil investigations.
  2. A complete record of the soil boring and penetration test logs and soil samples.
  3. A record of the soil profile.
  4. Elevation of the water table, if encountered. Historic high ground water elevations shall be addressed in the report to adequately evaluate liquefaction and settlement potential.
  5. Recommendations for foundation type and design criteria, including but not limited to: bearing capacity of natural or compacted soil; provisions to mitigate the effects of expansive soils; mitigation of the effects of liquefaction, differential settlement and varying soil strength; and the effects of adjacent loads.
  6. Expected total and differential settlement.
  7. Deep foundation information in accordance with Section 1803 A .5.5.
  8. Special design and construction provisions for foundations of structures founded on expansive soils, as necessary.
  9. Compacted fill material properties and testing in accordance with Section 1803 A .5.8.
  10. Controlled low-strength material properties and testing in accordance with Section 1803 A .5.9. 11. The report shall consider the effects of stepped footings addressed in Section 1809A.3. 12. The report shall consider the effects of seismic hazards in accordance with Section 1803A.6 and shall incorporate the associ- ated geohazard report.
• CBC § 2.4 High relevance — show source text

  SECTION 1802 A —DESIGN BASIS

  1802 A .1 General. Allowable bearing pressures, allowable stresses and design formulas provided in this chapter shall be used with the allowable stress design load combinations specified in ASCE 7, Section 2.4 or the alternative allowable stress design load combinations of Section 1605 A .2. The quality and design of materials used structurally in excavations and foundations shall comply with the requirements specified in Chapters 16, 19, 21, 22 and 23. Excavations and fills shall comply with Chapter 33.

  SECTION 1803 A —GEOTECHNICAL INVESTIGATIONS

  1803 A .1 General. Geotechnical investigations shall be conducted in accordance with Section 1803 A .2 and reported in accordance with Section 1803A.7. The classification and investigation of the soil shall be made under the responsible charge of a California regis- tered geotechnical engineer. All recommendations contained in geotechnical and geohazard reports shall be subject to the approval of the enforcement agency. All reports shall be prepared and signed by a registered geotechnical engineer, a certified engineering geolo- gist and a registered geophysicist, where applicable.

  1803 A .2 Investigations required. Geotechnical investigations shall be conducted in accordance with Sections 1803 A .3 through 1803A.6 .

  Exception s : 1. Geotechnical reports are not required for one-story, wood-frame and light-steel-frame buildings of Type II or Type V construction and 4,000 square feet (371 m [2] ) or less in floor area, not located within Earthquake Fault Zones or Seismic Hazard Zones as shown in the most recently published maps from the California Geological Survey (CGS) or in seismic hazard zones as defined in the Safety Element of the local General Plan. Allowable foundation and lateral soil pressure values may be determined from Table 1806A.2.

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  SOILS AND FOUNDATIONS

  2. A previous report for a specific site may be resubmitted, provided that a reevaluation is made and the report is found to be currently appropriate.

  1803 A .3 Basis of investigation. Soil classification shall be based on observation and any necessary tests of the materials disclosed by borings, test pits or other subsurface exploration made in appropriate locations. Additional studies shall be made as necessary to evaluate slope stability, soil strength, position and adequacy of load-bearing soils, the effect of moisture variation on soil-bearing capacity, compressibility, liquefaction and expansiveness.

• CBC § 4.3. High relevance — show source text

  4.3. Ground stabilization.

  4.4. Any combination of these measures and how they shall be considered in the design of the structure.

  1803.6 Reporting. Where geotechnical investigations are required, a written report of the investigations shall be submitted to the building official by the permit applicant at the time of permit application. This geotechnical report shall include, but need not be limited to, the following information:

  1. A plot showing the location of the soil investigations.

  2. A complete record of the soil boring and penetration test logs and soil samples.

  3. A record of the soil profile.

  4. Elevation of the water table, if encountered.

  5. Recommendations for foundation type and design criteria, including but not limited to: bearing capacity of natural or compacted soil; provisions to mitigate the effects of expansive soils; mitigation of the effects of liquefaction, differential settlement and varying soil strength; and the effects of adjacent loads.

  6. Expected total and differential settlement.

  7. Deep foundation information in accordance with Section 1803.5.5.

  8. Special design and construction provisions for foundations of structures founded on expansive soils, as necessary.

  9. Compacted fill material properties and testing in accordance with Section 1803.5.8.

  10. Controlled low-strength material properties and testing in accordance with Section 1803.5.9. 11. [OSHPD 1R, 2 & 5] The report shall consider the effects of seismic hazard in accordance with Section 1803.7.

  1803.7 Geohazard reports. [OSHPD 1R, 2 & 5] Geohazard reports shall be required for all proposed construction.

  Exceptions: 1. Reports are not required for one-story, wood-frame and light-steel-frame buildings of Type V skilled nursing or intermediate care facilities construction and 4,000 square feet (371 m [2] ) or less in floor area, not located within Earthquake Fault Zones or Seismic Hazard Zones as shown in the most recently published maps from the California Geological Survey (CGS); 2. Reports are not required for the following scopes of work in existing buildings:

  Nonstructural alterations, voluntary structural alterations without foundation work, and incidental structural additions or alterations, and structural repairs for other than earthquake damage. 3. A previous report for a specific site may be resubmitted, provided that a reevaluation is made and the report is found to be currently appropriate.

  The purpose of the geohazard report shall be to identify geologic and seismic conditions that may require project mitigations. The reports shall contain data which provide an assessment of the nature of the site and potential for earthquake damage based on appropriate investigations of the regional and site geology, project foundation conditions and the potential seismic shaking at the site. The report shall be prepared by a California-certified engineering geologist in consultation with a California-registered geotech- nical engineer.

  The preparation of the geohazard report shall consider the most recent CGS Note 48; Checklist for the Review of Engineering Geol- ogy and Seismology Reports for California Public School, Hospitals and Essential Services Buildings. In addition, the most recent version of CGS Special Publication 42: Earthquake Fault Zones, A Guide for Government Agencies, Property Owners / Developers, and Geoscience Practitioners for Assessing Fault Rupture Hazards in California, shall be considered for project sites proposed within an _Alquist-Priolo Earthquake Fault Zone.

• CBC § 1803.1.1.4 Medium relevance — show source text

  1803.1.1.4 Liability. A city, county, city and county, or other enforcement agency charged with the administration and enforce- ment of the provisions of Section 1803.1.1, is not liable for any injury which arises out of any act or omission of the city, county, city and county, other enforcement agency, or a public employee or any other person under Section 1803.1.1.

  1803.1.1.5 Alternate procedures. The governing body of any city, county, or city and county may enact an ordinance prescribing an alternate procedure which is equal to or more restrictive than the procedure specified in Section 1803.1.1.

  1803.2 Investigations required. Geotechnical investigations shall be conducted in accordance with Sections 1803.3 through 1803.5.

  Exception: The building official shall be permitted to waive the requirement for a geotechnical investigation where satisfactory data from adjacent areas is available that demonstrates an investigation is not necessary for any of the conditions in Sections 1803.5.1 through 1803.5.6 and Sections 1803.5.10 and 1803.5.11.

  [OSHPD 1R, 2 & 5] Geotechnical reports are not required for one-story, wood-frame and light-steel-frame buildings of Type V construction and 4,000 square feet (371 m [2] ) or less in floor area, not located within Earthquake Fault Zones or Seismic Hazard Zones as shown in the most recently published maps from the California Geological Survey (CGS). Allowable foundation and lateral soil pressure values may be determined from Table 1806.2.

  1803.3 Basis of investigation. Soil classification shall be based on observation and any necessary tests of the materials disclosed by borings, test pits or other subsurface exploration made in appropriate locations. Additional studies shall be made as necessary to evaluate slope stability, soil strength, position and adequacy of load-bearing soils, the effect of moisture variation on soil-bearing capacity, compressibility, liquefaction and expansiveness.

  1803.3.1 Scope of investigation. The scope of the geotechnical investigation including the number and types of borings or soundings, the equipment used to drill or sample, the in-situ testing equipment and the laboratory testing program shall be determined by a registered design professional.

  [OSHPD 1R, 2 & 5] There shall not be less than one boring or exploration shaft for each 5,000 square feet (465 m [2] ) of building area at the foundation level with a minimum of two provided for any one building. A boring may be considered to reflect subsurface conditions relevant to more than one building, subject to the approval of the enforcement agency.

  Borings shall be of sufficient size to permit visual examination of the soil in place or, in lieu thereof, cores shall be taken.

  Borings shall be of sufficient depth and size to adequately characterize subsurface conditions.

  Exception: Single-story Type V skilled nursing or intermediate care facilities utilizing wood-frame or light-steel frame construction.

  1803.4 Qualified representative. The investigation procedure and apparatus shall be in accordance with generally accepted engineering practice. The registered design professional shall have a fully qualified representative on site during all boring or sampling operations.

  1803.5 Investigated conditions. Geotechnical investigations shall be conducted as indicated in Sections 1803.5.1 through 1803.5.12.

• CBC § 1803.5.12 Medium relevance — show source text

  1803.5.12 Seismic Design Categories D through F. For structures assigned to Seismic Design Category D, E or F, the geotechnical investigation required by Section 1803.5.11 shall include all of the following as applicable:

  1. The determination of dynamic seismic lateral earth pressures on foundation walls and retaining walls supporting more than 6 feet (1.83 m) of backfill height due to design earthquake ground motions.
  2. The potential for liquefaction and soil strength loss evaluated for site peak ground acceleration, earthquake magnitude and source characteristics consistent with the maximum considered earthquake ground motions. Peak ground acceleration shall be determined based on one of the following: 2.1. A site-specific study in accordance with Chapter 21 of ASCE 7.

  2.2. In accordance with Section 11.8.3 of ASCE 7.

  3. An assessment of potential consequences of liquefaction and soil strength loss including, but not limited to, the following:

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  SOILS AND FOUNDATIONS

  3.1. Estimation of total and differential settlement.

  3.2. Lateral soil movement.

  3.3. Lateral soil loads on foundations.

  3.4. Reduction in foundation soil-bearing capacity and lateral soil reaction. 3.5. Soil downdrag and reduction in axial and lateral soil reaction for pile foundations. 3.6. Increases in soil lateral pressures on retaining walls.

  3.7. Flotation of buried structures.

  4. Discussion of mitigation measures such as, but not limited to, the following: 4.1. Selection of appropriate foundation type and depths. 4.2. Selection of appropriate structural systems to accommodate anticipated displacements and forces.

  4.3. Ground stabilization.

  4.4. Any combination of these measures and how they shall be considered in the design of the structure.

  1803.6 Reporting. Where geotechnical investigations are required, a written report of the investigations shall be submitted to the building official by the permit applicant at the time of permit application. This geotechnical report shall include, but need not be limited to, the following information:

  1. A plot showing the location of the soil investigations.

  2. A complete record of the soil boring and penetration test logs and soil samples.

  3. A record of the soil profile.

  4. Elevation of the water table, if encountered.

  5. Recommendations for foundation type and design criteria, including but not limited to: bearing capacity of natural or compacted soil; provisions to mitigate the effects of expansive soils; mitigation of the effects of liquefaction, differential settlement and varying soil strength; and the effects of adjacent loads.

  6. Expected total and differential settlement.

  7. Deep foundation information in accordance with Section 1803.5.5.

  8. Special design and construction provisions for foundations of structures founded on expansive soils, as necessary.

  9. Compacted fill material properties and testing in accordance with Section 1803.5.8.

  10. Controlled low-strength material properties and testing in accordance with Section 1803.5.9. 11. [OSHPD 1R, 2 & 5] The report shall consider the effects of seismic hazard in accordance with Section 1803.7.

  1803.7 Geohazard reports. [OSHPD 1R, 2 & 5] Geohazard reports shall be required for all proposed construction.

• CBC § 18A-5 Medium relevance — show source text

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  SOILS AND FOUNDATIONS

  1803A.6 Geohazard reports. Geohazard reports shall be required for all proposed construction.

  Exceptions: 1. Reports are not required for one-story, wood-frame and light-steel-frame buildings of Type II or Type V construction and 4,000 square feet (371 m [2] ) or less in floor area, not located within Earthquake Fault Zones or Seismic Hazard Zones as shown in the most recently published maps from the California Geological Survey (CGS) or in seismic hazard zones as defined in the Safety Element of the local General Plan. 2. Reports are not required for the following scopes of work in existing buildings: nonstructural alterations, voluntary struc- tural alterations without foundation work, or structural repairs for damage not caused by an earthquake. [OSHPD 1 & 4] Incidental structural additions or alterations.

  3. A previous report for a specific site may be resubmitted, provided that a reevaluation is made and the report is found to be currently appropriate.

  The purpose of the geohazard report shall be to identify geologic and seismic conditions that may require project mitigations. The reports shall contain data which provide an assessment of the nature of the site and potential for earthquake damage based on appro- priate investigations of the regional and site geology, project foundation conditions and the potential seismic shaking at the site. The report shall be prepared by a California-certified engineering geologist in consultation with a California-registered geotechnical engineer.

  The preparation of the geohazard report shall consider the most recent CGS Note 48; Checklist for the Review of Engineering Geology and Seismology Reports for California Public School, Hospitals and Essential Services Buildings. In addition, the most recent version of CGS Special Publication 42: Earthquake Fault Zones, A Guide for Government Agencies, Property Owners / Developers, and Geoscience Practitioners for Assessing Fault Rupture Hazards in California, shall be considered for project sites proposed within an Alquist-Priolo Earthquake Fault Zone. The most recent version of CGS Special Publication 117, Guidelines for Evaluating and Mitigating Seismic Hazards in California, shall be considered for project sites proposed within a Seismic Hazard Zone. All conclusions shall be fully supported by satisfactory data and analysis.

  In addition to requirements in Sections 1803A.5.11 and 1803A.5.12, the report shall include, but need not be limited to, the following: 1. Site geology. 2. Evaluation of the known active and potentially active faults, both regional and local. 3. Ground-motion parameters, as required by Sections 1613A and 1617A, and ASCE 7.

  1803A.7 Geotechnical reporting. Where geotechnical investigations are required, a written report of the investigations shall be submitted to the building official by the permit applicant at the time of permit application. The geotechnical report shall provide completed evaluations of the foundation conditions of the site and the potential geologic/seismic hazards affecting the site. The geotechnical report shall include, but shall not be limited to, site-specific evaluations of design criteria related to the nature and extent _of foundation materials, groundwater conditions, liquefaction potential, settlement potential and slope stability.

• CBC § 1703.1.1 Medium relevance — show source text

  1703.1.1 Independence. An approved agency shall be objective, competent and independent from the contractor responsible for the work being inspected. The agency shall disclose to the building official and the registered design professional in responsible charge possible conflicts of interest so that objectivity can be confirmed.

  1703.1.2 Equipment. An approved agency shall have adequate equipment to perform required tests. The equipment shall be periodically calibrated.

  1703.1.3 Personnel. An approved agency shall employ experienced personnel educated in conducting, supervising and evaluating tests and special inspections.

  1703.2 Written approval. Any material, appliance, equipment, system or method of construction meeting the requirements of this code shall be approved in writing after satisfactory completion of the required tests and submission of required test reports.

  1703.3 Record of approval. For any material, appliance, equipment, system or method of construction that has been approved, a record of such approval, including the conditions and limitations of the approval, shall be kept on file in the building official’s office and shall be available for public review at appropriate times.

  1703.4 Performance. Specific information consisting of test reports conducted by an approved agency in accordance with the appropriate referenced standards, or other such information as necessary, shall be provided for the building official to determine that the product, material or assembly meets the applicable code requirements.

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  SPECIAL INSPECTIONS AND TESTS

  [OSHPD 1R, 2 & 5] Tests performed by an independent approved testing agency/laboratory or under the responsible charge of a compe- tent approved independent Registered Design Professional shall be deemed to comply with requirements of this section. Test reports for structural tests shall be reviewed and accepted by an independent California licensed structural engineer.

  1703.4.1 Research and investigation. Sufficient technical data shall be submitted to the building official to substantiate the proposed use of any product, material or assembly. If it is determined that the evidence submitted is satisfactory proof of performance for the use intended, the building official shall approve the use of the product, material or assembly subject to the requirements of this code. The costs, reports and investigations required under these provisions shall be paid by the owner or the owner’s authorized agent.

  1703.4.2 Research reports. Supporting data, where necessary to assist in the approval of products, materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.

  1703.5 Labeling. Products, materials or assemblies required to be labeled shall be labeled in accordance with the procedures set forth in Sections 1703.5.1 through 1703.5.4.

  1703.5.1 Testing. An approved agency shall test a representative sample of the product, material or assembly being labeled to the relevant standard or standards. The approved agency shall maintain a record of the tests performed. The record shall provide sufficient detail to verify compliance with the test standard.

  1703.5.2 Inspection and identification. The approved agency shall periodically perform an inspection, which shall be in-plant if necessary, of the product or material that is to be labeled. The inspection shall verify that the labeled product, material or assembly is representative of the product, material or assembly tested.

• CBC § 5.11 Medium relevance — show source text

  ** For structures assigned to Seismic Design Category D, E or F, the geotechnical investigation required by Section 1803 A .5.11 shall include all of the following as applicable:

  1. The determination of dynamic seismic lateral earth pressures on foundation walls and retaining walls supporting more than 6 feet (1.83 m) of backfill height due to design earthquake ground motions.
  2. The potential for liquefaction and soil strength loss evaluated for site peak ground acceleration, earthquake magnitude and source characteristics consistent with the maximum considered earthquake ground motions. Peak ground acceleration shall be determined based on one of the following: 2.1. A site-specific study in accordance with Chapter 21 of ASCE 7.

  2.2. In accordance with Section 11.8.3 of ASCE 7.

  3. An assessment of potential consequences of liquefaction and soil strength loss including, but not limited to, the following:

  3.1. Estimation of total and differential settlement.

  3.2. Lateral soil movement.

  3.3. Lateral soil loads on foundations.

  3.4. Reduction in foundation soil-bearing capacity and lateral soil reaction. 3.5. Soil downdrag and reduction in axial and lateral soil reaction for pile foundations. 3.6. Increases in soil lateral pressures on retaining walls.

  3.7. Flotation of buried structures.

  4. Discussion of mitigation measures such as, but not limited to, the following: 4.1. Selection of appropriate foundation type and depths. 4.2. Selection of appropriate structural systems to accommodate anticipated displacements and forces.

  4.3. Ground stabilization.

  4.4. Any combination of these measures and how they shall be considered in the design of the structure.

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  SOILS AND FOUNDATIONS

  1803A.6 Geohazard reports. Geohazard reports shall be required for all proposed construction.

  Exceptions: 1. Reports are not required for one-story, wood-frame and light-steel-frame buildings of Type II or Type V construction and 4,000 square feet (371 m [2] ) or less in floor area, not located within Earthquake Fault Zones or Seismic Hazard Zones as shown in the most recently published maps from the California Geological Survey (CGS) or in seismic hazard zones as defined in the Safety Element of the local General Plan. 2. Reports are not required for the following scopes of work in existing buildings: nonstructural alterations, voluntary struc- tural alterations without foundation work, or structural repairs for damage not caused by an earthquake. [OSHPD 1 & 4] Incidental structural additions or alterations.

  3. A previous report for a specific site may be resubmitted, provided that a reevaluation is made and the report is found to be currently appropriate.

  The purpose of the geohazard report shall be to identify geologic and seismic conditions that may require project mitigations. The reports shall contain data which provide an assessment of the nature of the site and potential for earthquake damage based on appro- priate investigations of the regional and site geology, project foundation conditions and the potential seismic shaking at the site. The report shall be prepared by a California-certified engineering geologist in consultation with a California-registered geotechnical engineer.

• CBC § 1803.5.6 Medium relevance — show source text

  1803.5.6 Rock strata. Where foundations are to be constructed on or in rock, the geotechnical investigation shall assess variations in rock strata depth, competency and load-bearing capacity.

  1803.5.7 Excavation near foundations. Where excavation will reduce support from any foundation, a registered design professional shall prepare an assessment of the structure as determined from examination of the structure, available design documents, available subsurface data, and, if necessary, excavation of test pits. The registered design professional shall determine the requirements for support and protection of any existing foundation and prepare site-specific plans, details and sequence of work for submission. Such support shall be provided by under-pinning, bracing, excavation retention systems or by other means acceptable to the building official.

  1803.5.8 Compacted fill material. Where shallow foundations will bear on compacted fill material more than 12 inches (305 mm) in depth, a geotechnical investigation shall be conducted and shall include all of the following:

  1. Specifications for the preparation of the site prior to placement of compacted fill material.

  2. Specifications for material to be used as compacted fill.

  3. Test methods to be used to determine the maximum dry density and optimum moisture content of the material to be used as compacted fill.

  4. Maximum allowable thickness of each lift of compacted fill material.

  5. Field test method for determining the in-place dry density of the compacted fill.

  6. Minimum acceptable in-place dry density expressed as a percentage of the maximum dry density determined in accordance with Item 3.

  7. Number and frequency of field tests required to determine compliance with Item 6.

  1803.5.9 Controlled low-strength material (CLSM). Where shallow foundations will bear on controlled low-strength material (CLSM), a geotechnical investigation shall be conducted and shall include all of the following:

  1. Specifications for the preparation of the site prior to placement of the CLSM.
  2. Specifications for the CLSM.
  3. Laboratory or field test method(s) to be used to determine the compressive strength or bearing capacity of the CLSM .
  4. Test methods for determining the acceptance of the CLSM in the field.
  5. Number and frequency of field tests required to determine compliance with Item 4.

  1803.5.10 Alternate setback and clearance. Where setbacks or clearances other than those required in Section 1808.7 are desired, the building official shall be permitted to require a geotechnical investigation by a registered design professional to demonstrate that the intent of Section 1808.7 would be satisfied. Such an investigation shall include consideration of material, height of slope, slope gradient, load intensity and erosion characteristics of slope material.

  1803.5.11 Seismic Design Categories C through F. For structures assigned to Seismic Design Category C, D, E or F, a geotechnical investigation shall be conducted, and shall include an evaluation of all of the following potential geologic and seismic hazards:

  1. Slope instability.

  2. Liquefaction.

  3. Total and differential settlement.

  4. Surface displacement due to faulting or seismically induced lateral spreading or lateral flow.