Seismic requirements, ACI coordination and reinforcement rules

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

• CBC § 0.005 High relevance — show source text

  Not fewer than four longitudinal bars, with a minimum longitudinal reinforcement ratio of 0.005, shall be provided throughout the minimum reinforced length of the element as defined in this section starting at the top of the element. The minimum reinforced length of the element shall be taken as the greatest of the following:

  1. One-half of the element length.

  2. A distance of 10 feet (3048 mm).

  3. Three times the least element dimension.

  2025 CALIFORNIA BUILDING CODE 18A-21

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  SOILS AND FOUNDATIONS

  4. The distance from the top of the element to the point where the design cracking moment determined in accordance with Section 1810 A .3.9.1 exceeds the required moment strength determined using the load combinations of ASCE 7, Section 2.3.

  Transverse reinforcement shall consist of closed ties or spirals not smaller than No. 3 bars for elements with a least dimension up to 20 inches (508 mm), and No. 4 bars for larger elements. Throughout the remainder of the reinforced length outside the regions with transverse confinement reinforcement, as specified in Section 1810 A .3.9.4.2.1 or 1810 A .3.9.4.2.2, the spacing of transverse reinforcement shall not exceed the least of the following:

  1. 12 longitudinal bar diameters.

  2. One-half the least dimension of the element.

  3. 12 inches (305 mm).

  Exceptions:

  1. The requirements of this section shall not apply to concrete cast in structural steel pipes or tubes.
  2. A spiral-welded metal casing of a thickness not less than manufacturer’s standard No. 14 gage (0.068 inch) is permitted to provide concrete confinement in lieu of the closed ties or spirals. Where used as such, the metal casing shall be protected against possible deleterious action due to soil constituents, changing water levels or other factors indicated by boring records of site conditions.

  1810 A .3.9.4.2.1 Site Classes A through DE. For Site Class A, B, BC, C, CD, D or DE sites, transverse confinement reinforcement shall be provided in the element in accordance with Sections 18.7.5.2, 18.7.5.3 and 18.7.5.4 of ACI 318 within three times the least element dimension at the bottom of the pile cap. A transverse spiral reinforcement ratio of not less than one-half of that required in Table 18.10.6.4(g) of ACI 318 shall be permitted for concrete deep foundation elements.

  1810 A .3.9.4.2.2 Site Classes E and F. For Site Class E or F sites, transverse confinement reinforcement shall be provided in the element in accordance with Sections 18.7.5.2, 18.7.5.3 and 18.7.5.4 of ACI 318 within seven times the least element dimension at the bottom of the pile cap and within seven times the least element dimension at the interfaces of strata that are hard or stiff and strata that are liquefiable or are composed of soft- to medium-stiff clay.

• CBC § 1810.3.10.4.1 High relevance — show source text

  1810.3.10.4.1 Seismic requirements. [OSHPD 1R, 2 & 5] For structures assigned to Seismic Design Category D, E or F, a perma- nent steel casing having a minimum thickness of [3] / 8 inch shall be provided from the top of the micropile down to a minimum of 120 percent of the point of zero curvature. Capacity of micropiles shall be determined in accordance with Section 1810.3.3 by at least two project specific pre-production tests for each soil profile, size and depth of micropile. At least two percent of all produc- tion piles shall be proof tested to design strength determined by using load combinations in ASCE 7, Section 2.3.6.

  Steel casing length in soil shall be considered as unbonded and shall not be considered as contributing to friction. Casing shall provide confinement at least equivalent to hoop reinforcing required by ACI 318 Section 18.13.5.

  Reinforcement shall have Class 1 corrosion protection in accordance with PTI Recommendations for Prestressed Rock and Soil Anchors. Steel casing design shall include at least [1] / 16 -inch corrosion allowance.

  Micropiles shall not be considered as carrying any horizontal loads.

  1810.3.11 Pile caps. Pile caps shall conform with ACI 318 and this section. Pile caps shall be of reinforced concrete, and shall include all elements to which vertical deep foundation elements are connected, including grade beams and mats. The soil immediately below the pile cap shall not be considered as carrying any vertical load, with the exception of a combined pile raft. [OSHPD 1R, 2 & 5] A combined pile raft foundation shall be an alternative system. The tops of vertical deep foundation elements shall be embedded not less than 3 inches (76 mm) into pile caps and the caps shall extend not less than 4 inches (102 mm) beyond the edges of the elements. The tops of elements shall be cut or chipped back to sound material before capping.

  1810.3.11.1 Seismic Design Categories C through F. For structures assigned to Seismic Design Category C, D, E or F, concrete deep foundation elements shall be connected to the pile cap in accordance with ACI 318.

  For resistance to uplift forces, anchorage of steel pipes, tubes or H-piles to the pile cap shall be made by means other than concrete bond to the bare steel section. Concrete-filled steel pipes or tubes shall have reinforcement of not less than 0.01 times the cross-sectional area of the concrete fill developed into the cap and extending into the fill a length equal to two times the required cap embedment, but not less than the development length in tension of the reinforcement.

  1810.3.11.2 Seismic Design Categories D through F. For structures assigned to Seismic Design Category D, E or F, deep foundation element resistance to uplift forces or rotational restraint shall be provided by anchorage into the pile cap, designed considering the combined effect of axial forces due to uplift and bending moments due to fixity to the pile cap. Anchorage shall develop not less than 25 percent of the strength of the element in tension. Anchorage into the pile cap shall comply with the following:

  1. In the case of uplift, the anchorage shall be capable of developing the least of the following: 1.1. The nominal tensile strength of the longitudinal reinforcement in a concrete element. 1.2.
• CBC § 1810A.3.10.4 High relevance — show source text

  1810A.3.10.4 Seismic requirements. For structures assigned to Seismic Design Category D, E or F, a permanent steel casing having a minimum thickness of [3] / 8 inch shall be provided from the top of the micropile down to a minimum of 120 percent of the point of zero curvature. Capacity of micropiles shall be determined in accordance with Section 1810A.3.3 by at least two project- specific preproduction tests for each soil profile, size and depth of micropile. At least two percent of all production piles shall be proof tested to the load determined in accordance with Section 1617A.1.15.

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  SOILS AND FOUNDATIONS

  Steel casing length in soil shall be considered as unbonded and shall not be considered as contributing to friction. Casing shall provide confinement at least equivalent to hoop reinforcing required by ACI 318 Section 18.13.5.

  Reinforcement shall have Class 1 corrosion protection in accordance with PTI Recommendations for Prestressed Rock and Soil Anchors. Steel casing design shall include at least [1] / 16 -inch corrosion allowance.

  Micropiles shall not be considered as carrying any horizontal loads.

  1810 A .3.11 Pile caps. Pile caps shall conform with ACI 318 and this section. Pile caps shall be of reinforced concrete, and shall include all elements to which vertical deep foundation elements are connected, including grade beams and mats. The soil immediately below the pile cap shall not be considered as carrying any vertical load, with the exception of a combined pile raft. A combined pile raft foundation shall be an alternate system. The tops of vertical deep foundation elements shall be embedded not less than 3 inches (76 mm) into pile caps and the caps shall extend not less than 4 inches (102 mm) beyond the edges of the elements. The tops of elements shall be cut or chipped back to sound material before capping.

  1810 A .3.11.1 Seismic Design Categories C through F. For structures assigned to Seismic Design Category C, D, E or F, concrete deep foundation elements shall be connected to the pile cap in accordance with ACI 318.

  For resistance to uplift forces, anchorage of steel pipes, tubes or H-piles to the pile cap shall be made by means other than concrete bond to the bare steel section. Concrete-filled steel pipes or tubes shall have reinforcement of not less than 0.01 times the cross-sectional area of the concrete fill developed into the cap and extending into the fill a length equal to two times the required cap embedment, but not less than the development length in tension of the reinforcement.

  1810 A .3.11.2 Seismic Design Categories D through F. For structures assigned to Seismic Design Category D, E or F, deep foundation element resistance to uplift forces or rotational restraint shall be provided by anchorage into the pile cap, designed considering the combined effect of axial forces due to uplift and bending moments due to fixity to the pile cap. Anchorage shall develop not less than 25 percent of the strength of the element in tension. Anchorage into the pile cap shall comply with the following: 1.

• CBC § 0.068 High relevance — show source text

  Exceptions:

  1. The requirements of this section shall not apply to concrete cast in structural steel pipes or tubes.
  2. A spiral-welded metal casing of a thickness not less than the manufacturer’s standard No. 14 gage (0.068 inch) is permitted to provide concrete confinement in lieu of the closed ties or spirals. Where used as such, the metal casing shall be protected against possible deleterious action due to soil constituents, changing water levels or other factors indicated by boring records of site conditions.

  1810.3.9.4.2 Seismic reinforcement in Seismic Design Categories D through F. For structures assigned to Seismic Design Category D, E or F, cast-in-place deep foundation elements shall be reinforced as specified in this section. Reinforcement shall be provided where required by analysis.

  Not fewer than four longitudinal bars, with a minimum longitudinal reinforcement ratio of 0.005, shall be provided throughout the minimum reinforced length of the element as defined in this section starting at the top of the element. The minimum reinforced length of the element shall be taken as the greatest of the following:

  1. One-half of the element length.

  2. A distance of 10 feet (3048 mm).

  3. Three times the least element dimension.

  4. The distance from the top of the element to the point where the design cracking moment determined in accordance with Section 1810.3.9.1 exceeds the required moment strength determined using the load combinations of ASCE 7, Section 2.3.

  Transverse reinforcement shall consist of closed ties or spirals not smaller than No. 3 bars for elements with a least dimension up to 20 inches (508 mm), and No. 4 bars for larger elements. Throughout the remainder of the reinforced length outside the regions with transverse confinement reinforcement, as specified in Section 1810.3.9.4.2.1 or 1810.3.9.4.2.2, the spacing of transverse reinforcement shall not exceed the least of the following:

  1. 12 longitudinal bar diameters.

  2. One-half the least dimension of the element.

  3. 12 inches (305 mm).

  Exceptions:

  1. The requirements of this section shall not apply to concrete cast in structural steel pipes or tubes.
  2. A spiral-welded metal casing of a thickness not less than manufacturer’s standard No. 14 gage (0.068 inch) is permitted to provide concrete confinement in lieu of the closed ties or spirals. Where used as such, the metal casing shall be protected against possible deleterious action due to soil constituents, changing water levels or other factors indicated by boring records of site conditions.

  1810.3.9.4.2.1 Site Classes A through DE. For Site Class A, B, BC, C, CD, D or DE sites, transverse confinement reinforcement shall be provided in the element in accordance with Sections 18.7.5.2, 18.7.5.3 and 18.7.5.4 of ACI 318 within three times the least element dimension of the bottom of the pile cap. A transverse spiral reinforcement ratio of not less than one-half of that required in Table 18.10.6.4(g) of ACI 318 shall be permitted.

• CBC § 26.10 High relevance — show source text

  Application of prestressing forces.|X|—|ACI 318: 26.10|ACI 318: 26.10| |9.|b. Grouting of bonded prestressing tendons.|X|—|—|—| |10.|Inspect erection of precast concrete members.|—|X|ACI 318: 26.9|—| |11.|For precast concrete diaphragm connections or reinforcement at
  joints classified as moderate or high deformability elements (MDE
  or HDE) in structures assigned to Seismic Design Category C, D, E
  or F, inspect such connections and reinforcement in the field for:|||ACI 318:
  26.13.1.3
  ACI 550.5|—| |11.|a. Installation of the embedded parts.|X|—|—|—| |11.|b. Completion of the continuity of reinforcement across joints.|X|—|—|—| |11.|c. Completion of connections in the field.|X|—|—|—| |12.|Inspect installation tolerances of precast concrete diaphragm
  connections for compliance with ACI 550.5.|—|X|ACI 318:
  26.13.1.3|—| |13.|Verify in-situ concrete strength, prior to stressing of tendons in
  posttensioned concrete and prior to removal of shores and forms
  from beams and structural slabs.|—|X|ACI 318: 26.11.2|—| |14.|Inspect formwork for shape, location and dimensions of the
  concrete member being formed.|—|X|ACI 318:
  26.11.1.2(b)|—| |For SI: 1 inch = 25.4 mm.
  a. Where applicable, see Section 1705.13.
  b. Specific requirements for special inspection shall be included in the research report for the anchor issued by an approved source in accordance with 26.13 in ACI 318, or other
  qualification procedures. Where specific requirements are not provided, special inspection requirements shall be specified by the registered design professional and shall be
  approved by the building official prior to the commencement of the work.
  c._ [OSHPD 1R, 2 & 5]_Installation of all adhesive anchors in horizontal and upwardly inclined positions shall be performed by an ACI/CRSI Certified Adhesive Anchor Installer, except
  where the factored design tension on the anchors is less than 100 pounds and those anchors are clearly noted on the approved construction documents or where the anchors are
  shear dowels across cold joints in slabs on grade where the slab is not part of the lateral force-resisting system.|For SI: 1 inch = 25.4 mm.
  a. Where applicable, see Section 1705.13.
  b. Specific requirements for special inspection shall be included in the research report for the anchor issued by an approved source in accordance with 26.13 in ACI 318, or other
  qualification procedures.

• CBC § 1810.2.2 High relevance — show source text

  Where deep foundation elements of the same type are being spliced, splices shall develop not less than 50 percent of the bending strength of the weaker section. Where deep foundation elements of different materials or different types are being spliced, splices shall develop the full compressive strength and not less than 50 percent of the tension and bending strength of the weaker section. Where structural steel cores are to be spliced, the ends shall be milled or ground to provide full contact and shall be full-depth welded.

  Exception: For buildings assigned to Seismic Design Category A or B, splices need not comply with the 50-percent tension and bending strength requirements where justified by supporting data.

  Splices occurring in the upper 10 feet (3048 mm) of the embedded portion of an element shall be designed to resist at allowable stresses the moment and shear that would result from an assumed eccentricity of the axial load of 3 inches (76 mm), or the element shall be braced in accordance with Section 1810.2.2 to other deep foundation elements that do not have splices in the upper 10 feet (3048 mm) of embedment.

  1810.3.6.1 Seismic Design Categories C through F. For structures assigned to Seismic Design Category C, D, E or F splices of deep foundation elements shall develop the lesser of the following:

  1. The nominal strength of the deep foundation element.
  2. The axial and shear forces and moments from the seismic load effects including overstrength factor in accordance with Section 2.3.6 or 2.4.5 of ASCE 7.

  1810.3.7 Top of element detailing at cutoffs. Where a minimum length for reinforcement or the extent of closely spaced confinement reinforcement is specified at the top of a deep foundation element, provisions shall be made so that those specified lengths or extents are maintained after cutoff.

  1810.3.8 Precast concrete piles. Precast concrete piles shall be designed and detailed in accordance with ACI 318.

  Exceptions:

  1. For precast prestressed piles in Seismic Design Category C, the minimum volumetric ratio of spirals or circular hoops required by Section 18.13.5.10.4 of ACI 318 shall not apply in cases where the design includes full consideration of load combinations specified in ASCE 7, Section 2.3.6 or Section 2.4.5 and the applicable overstrength factor, Ω 0 . In such cases, minimum transverse reinforcement index shall be as specified in Section 13.4.5.6 of ACI 318. [OSHPD 1R, 2 & 5] not permitted by OSHPD.
  2. For precast prestressed piles in Seismic Design Categories D through F and in Site Class A, B, BC, C, CD, D or DE sites, the minimum volumetric ratio of spirals or circular hoops required by Section 18.13.5.10.5(c) of ACI 318 shall not apply in cases where the design includes full consideration of load combinations specified in ASCE 7, Section 2.3.6 or Section 2.4.5 and the applicable overstrength factor, Ω 0 . In such cases, minimum transverse reinforcement shall be as specified in Section 13.4.5.6 of ACI 318. [OSHPD 1R, 2 & 5] not permitted by OSHPD.
• CBC § 1901.2 High relevance — show source text

  1901.2 Plain and reinforced concrete. Structural concrete shall be designed and constructed in accordance with the requirements of this chapter and ACI 318 as supplemented in Section 1905 of this code.

  1901.2.1 Structural concrete with GFRP reinforcement. Cast-in-place structural concrete internally reinforced with glass fiber reinforced polymer (GFRP) reinforcement conforming to ASTM D7957 and designed in accordance with ACI CODE 440.11 shall be permitted where fire-resistance ratings are not required and only for structures assigned to Seismic Design Category A.

  1901.3 Anchoring to concrete. Anchoring to concrete shall be in accordance with ACI 318 as supplemented in Section 1905, and applies to cast-in (headed bolts, headed studs and hooked J- or L-bolts), post-installed expansion (torque-controlled and displacement-controlled), undercut, screw, and adhesive anchors.

  1901.3.1 Power actuated fasteners. [OSHPD 1R, 2 & 5] Power actuated fasteners qualified in accordance with ICC-ES AC 70 shall be deemed to satisfy the requirements of ASCE 7, Section 13.4.5.

  Power actuated fasteners shall be permitted in seismic shear for components exempt from construction documents review by ASCE 7, Section 13.1.4 and for interior non-bearing non-shear wall partitions only. Power actuated fastener shall not be used to anchor seismic bracing, exterior cladding or curtain wall systems.

  Exception: Power actuated fasteners in steel to steel connections prequalified for seismic application by cyclic tests in accordance with ICC-ES AC 70 shall be permitted for seismic design.

  1901.3.2 Mechanical anchors and specialty inserts. [OSHPD 1R, 2 & 5] Mechanical anchors qualified in accordance with ICC-ES AC 193 shall be deemed to satisfy the requirements of this section. Specialty inserts, including cast-in-place specialty inserts, tested in accordance with ICC-ES AC 232 or AC 446 shall be deemed to satisfy the requirements of this section.

  Note: The removal and resetting of post-installed mechanical anchors are prohibited by ACI 318 Section 17.1.3.

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  CONCRETE

  1901.3.3 Post-installed adhesive anchors. [OSHPD 1R, 2 & 5] Post-installed reinforcing bars, adhesive anchors, and torque- controlled adhesive anchors qualified in accordance with ICC-ES AC 308 shall be deemed to satisfy the requirements of this section.

  1901.3.4 Proof tests for post-installed anchors in concrete. [OSHPD 1R, 2 & 5] When post-installed anchors are used in lieu of cast- in place bolts, the proof test loads, frequency and acceptance criteria shall be in accordance with this section.

  Exceptions. Proof tests are not required for the following:

  1. Undercut anchors that allow visual confirmation of full set.

• CBC § 1810.3.8 High relevance — show source text

  1810.3.8 Precast concrete piles. Precast concrete piles shall be designed and detailed in accordance with ACI 318.

  Exceptions:

  1. For precast prestressed piles in Seismic Design Category C, the minimum volumetric ratio of spirals or circular hoops required by Section 18.13.5.10.4 of ACI 318 shall not apply in cases where the design includes full consideration of load combinations specified in ASCE 7, Section 2.3.6 or Section 2.4.5 and the applicable overstrength factor, Ω 0 . In such cases, minimum transverse reinforcement index shall be as specified in Section 13.4.5.6 of ACI 318. [OSHPD 1R, 2 & 5] not permitted by OSHPD.
  2. For precast prestressed piles in Seismic Design Categories D through F and in Site Class A, B, BC, C, CD, D or DE sites, the minimum volumetric ratio of spirals or circular hoops required by Section 18.13.5.10.5(c) of ACI 318 shall not apply in cases where the design includes full consideration of load combinations specified in ASCE 7, Section 2.3.6 or Section 2.4.5 and the applicable overstrength factor, Ω 0 . In such cases, minimum transverse reinforcement shall be as specified in Section 13.4.5.6 of ACI 318. [OSHPD 1R, 2 & 5] not permitted by OSHPD.

  [OSHPD 1R, 2 & 5] Exception: Where the axial load from seismic forces is amplified by the applicable overstrength factor, Ω 0 , the axial load limits in Section 18.13.5.10.6 of ACI 318 may be increased by two times.

  1810.3.9 Cast-in-place deep foundations. Cast-in-place deep foundation elements shall be designed and detailed in accordance with Sections 1810.3.9.1 through 1810.3.9.6.

  1810.3.9.1 Design cracking moment. The design cracking moment ( φ M n ) for a cast-in-place deep foundation element not enclosed by a structural steel pipe or tube shall be determined using the following equation:

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  SOILS AND FOUNDATIONS

  Equation 18-5

  φ M n = 3 f ′ c S m

  For SI: φ M n = 0.25 f ′ c S m

  where:

  f ′ c = Specified compressive strength of concrete or grout, psi (MPa). S m = Elastic section modulus, neglecting reinforcement and casing, cubic inches (mm [3] ).

• CBC § 1903.5 High relevance — show source text

  1903.5 Welding of reinforcing bars - [OSHPD 1R, 2 & 5] Modify ACI 318 Section 26.6.4.1(b) by adding the following:

  Subject to prior approval of the enforcing agency, longitudinal holding wires conforming to ASTM A1064, of maximum wire size W5, that are machine resistance welded to stirrup/tie cage (or spiral assemblies) consisting of low alloy steel reinforcing conforming to ASTM A706 are permitted when performed under continuous competent control in a fabrication shop. Tack welding of primary rein- forcing bars together or to stirrups/ties is not permitted. Holding wire weld locations shall not occur on any longitudinal or primary reinforcing nor on any portion of a reinforcing bar that is or will be bent in accordance with ACI 318 Section 25.3 for the extents speci- fied in AWS D1.4 Section 4.2.6.

  Quality control tests shall be performed on shop welded specimens by the fabricator. Reinforcing steel specimens containing the holding wire shall be tested for yield and tensile strength at the frequency required by Section 1910.2. Test reports shall be available on request to the approved agency, design professional and enforcement agency.

  SECTION 1904—DURABILITY REQUIREMENTS

  1904.1 Structural concrete. Structural concrete shall conform to the durability requirements of ACI 318.

  Exception: For Group R-2 and R-3 occupancies not more than three stories above grade plane, the specified compressive strength, f´ c, for concrete in basement walls, foundation walls, exterior walls and other vertical surfaces exposed to the weather shall be not less than 3,000 psi (20.7 MPa).

  1904.2 Nonstructural concrete. The registered design professional shall assign nonstructural concrete a freeze-thaw exposure class, as defined in ACI 318, based on the anticipated exposure of nonstructural concrete. Nonstructural concrete shall have a minimum specified compressive strength, f´ c, of 2,500 psi (17.2 MPa) for Class F0; 3,000 psi (20.7 MPa) for Class F1; and 3,500 psi (24.1 MPa) for Classes F2 and F3. Nonstructural concrete shall be air entrained in accordance with ACI 318.

  SECTION 1905—SEISMIC REQUIREMENTS

  1905.1 General. In addition to the provisions of ACI 318, structural concrete shall comply with the requirements of Section 1905.

  1905.2 ACI 318 Section 2.3. Modify existing definitions and add the following definitions to ACI 318 Section 2.3:

  CAST-IN-PLACE CONCRETE EQUIVALENT DIAPHRAGM. A cast-in-place noncomposite topping slab diaphragm, as defined in Section 18.12.5, or a diaphragm constructed with precast concrete components that uses closure strips between precast components with detailing that meets the requirements of ACI 318 for the Seismic Design Category of the structure.

  DETAILED PLAIN CONCRETE STRUCTURAL WALL. A wall complying with the requirements of Chapter 14, and Section 1905.5 of the California Building Code .

  ORDINARY PLAIN CONCRETE STRUCTURAL WALL. A wall complying with the requirements of Chapter 14, excluding 14.6.2.

• CBC § 1903A.4 High relevance — show source text

  1903A.4 Steel fiber reinforcement – Not permitted.

  1903A.5 Welding of reinforcing bars - Modify ACI 318 Section 26.6.4.2(b) by adding the following:

  Subject to prior approval of the enforcing agency, longitudinal holding wires, conforming to ASTM A1064 of maximum wire size W5, that are machine resistance welded to stirrup/tie cage (or spiral assemblies) consisting of low alloy steel reinforcing conforming to ASTM A706 are permitted when performed under continuous competent control in a fabrication shop. Tack welding of primary reinforcing bars together or to stirrups/ties is not permitted. Holding wire weld locations shall not occur on any longitudinal or primary reinforcing nor on any portion of a reinforcing bar that is or will be bent in accordance with ACI 318 Section 25.3 for the extents specified in AWS D1.4 Section 4.2.6.

  [DSA-SS] Exception: Mat reinforcing for slabs or isolated footings shall be permitted to have holding wires located no more than six bar diameters from the free end of reinforcing. Such free ends shall not be associated with any welded splices, couplers or other free- end modifications involving reinforcement development.

  Quality control tests shall be performed on shop-welded specimens by the fabricator. Reinforcing steel specimens containing the holding wire shall be tested for yield and tensile strength at the frequency required by Section 1910A.2. Test reports shall be available on request to the approved agency, design professional and enforcement agency.

  SECTION 1904 A —DURABILITY REQUIREMENTS

  1904 A .1 Structural concrete. Structural concrete shall conform to the durability requirements of ACI 318.

  1904 A .2 Nonstructural concrete. The registered design professional shall assign nonstructural concrete a freeze-thaw exposure class, as defined in ACI 318, based on the anticipated exposure of nonstructural concrete. Nonstructural concrete shall have a minimum specified compressive strength, f´ c, of 2,500 psi (17.2 MPa) for Class F0; 3,000 psi (20.7 MPa) for Class F1; and 3,500 psi (24.1 MPa) for Classes F2 and F3. Nonstructural concrete shall be air entrained in accordance with ACI 318.

  SECTION 1905 A —SEISMIC REQUIREMENTS

  1905 A .1 General. In addition to the provisions of ACI 318, structural concrete shall comply with the requirements of Section 1905 A .

  1905 A .2 ACI 318 Section 2.3. Modify existing definitions and add the following definitions to ACI 318 Section 2.3:

  CAST-IN-PLACE CONCRETE EQUIVALENT DIAPHRAGM. A cast-in-place noncomposite topping slab diaphragm, as defined in Section 18.12.5, or a diaphragm constructed with precast concrete components that uses closure strips between precast components with detailing that meets the requirements of ACI 318 for the Seismic Design Category of the structure.

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  CONCRETE

• CBC § 26.13.3 High relevance — show source text

  Inspect welding of reinforcement for special moment frames,
  boundary elements of special structural walls and coupling
  beams.|X|—|AWS D1.4
  ACI 318: 26.13.3|AWS D1.4
  ACI 318: 26.13.3| |2.|c. Inspect welded reinforcement splices.|X|—|—|—| |2.|d. Inspect welding of primary tension reinforcement in corbels.|X|—|—|—| |2.|e. Inspect single-pass fillet welds, maximum5/16″.|—|X|AWS D1.4
  ACI 318: 26.13.3|AWS D1.4
  ACI 318: 26.13.3| |2.|f. Inspect all other welds.|—|X|AWS D1.4
  ACI 318: 26.13.3|AWS D1.4
  ACI 318: 26.13.3| |3.|Inspect anchors cast in concrete.|—|X|ACI 318:
  26.13.3.3|—| |4.|Inspect anchors post-installed in hardened concrete members:b||||—| |4.|a. Adhesive anchors installed in horizontally or upwardly
  inclined orientations to resist sustained tension loads.c|X|—|ACI 318:
  26.13.3.2|| |4.|b. Mechanical anchors and adhesive anchors not defined in 4.a.|—|X|ACI 318: 26.13.3|| |5.|Verify use of required design mix.|—|X|ACI 318: Ch. 19,
  26.4.3, 26.4.4|1904.1, 1904.2| |6.|Prior to concrete placement, fabricate specimens for strength
  tests, perform slump and air content tests, and determine the
  temperature of the concrete.|X|—|ASTM C31
  ASTM C172
  ACI 318: 26.5,
  26.12|—| |7.|Inspect concrete and shotcrete placement for proper application
  techniques.|X|—|ACI 318: 26.5|—| |8.|Verify maintenance of specified curing temperature and
  techniques.|—|X|ACI 318: 26.5.3-
  26.5.5|—| |9.|Inspect prestressed concrete for:||||—| |9.|a. Application of prestressing forces.|X|—|ACI 318: 26.10|ACI 318: 26.10| |9.|b. Grouting of bonded prestressing tendons.|X|—|—|—| |10.|Inspect erection of precast concrete members.|—|X|ACI 318: 26.9|—| |11.|For precast concrete diaphragm connections or reinforcement at
  joints classified as moderate or high deformability elements (MDE
  or HDE) in structures assigned to Seismic Design Category C, D, E
  or F, inspect such connections and reinforcement in the field for:|||ACI 318:
  26.13.1.3
  ACI 550.5|—| |11.|a. Installation of the embedded parts.|X|—|—|—| |11.|b. Completion of the continuity of reinforcement across joints.|X|—|—|—| |11.|c.

• CBC § 1810.3.1.3 High relevance — show source text

  1810.3.1.3 Mislocation. The foundation or superstructure shall be designed to resist the effects of the mislocation of any deep foundation element by not less than 3 inches (76 mm). To resist the effects of mislocation, compressive overload of deep foundation elements to 110 percent of the allowable design load shall be permitted.

  1810.3.1.4 Driven piles. Driven piles shall be designed and manufactured in accordance with accepted engineering practice to resist all stresses induced by handling, driving and service loads.

  1810.3.1.5 Helical piles. Helical piles shall be designed and manufactured in accordance with accepted engineering practice to resist all stresses induced by installation into the ground and service loads.

  1810.3.1.5.1 Helical piles seismic requirements. [OSHPD 1R, 2 & 5] For structures assigned to Seismic Design Category D, E or F, capacities of helical piles shall be determined in accordance with Section 1810.3.3 by at least two project specific pre-produc- tion tests for each soil profile, size and depth of helical pile. At least two percent of all production piles shall be proof tested to design strength determined by using load combinations in ASCE 7, Section 2.3.6.

  Helical piles shall satisfy corrosion resistance requirements of ICC-ES AC 358. In addition, all helical pile materials that are subject to corrosion shall include at least [1] / 16 inch corrosion allowance.

  Helical piles shall not be considered as carrying any horizontal loads.

  1810.3.1.6 Casings. Temporary and permanent casings shall be of steel and shall be sufficiently strong to resist collapse and sufficiently watertight to exclude any foreign materials during the placing of concrete. Where a permanent casing is considered reinforcing steel, the steel shall be protected under the conditions specified in Section 1810.3.2.5. Horizontal joints in the casing shall be spliced in accordance with Section 1810.3.6.

  1810.3.2 Materials. The materials used in deep foundation elements shall satisfy the requirements of Sections 1810.3.2.1 through 1810.3.2.8, as applicable.

  1810.3.2.1 Concrete. Where concrete is cast in a steel pipe or where an enlarged base is formed by compacting concrete, the maximum size for coarse aggregate shall be [3] / 4 inch (19.1 mm). Concrete to be compacted shall have a zero slump.

  1810.3.2.1.1 Seismic hooks. For structures assigned to Seismic Design Category C, D, E or F, the ends of hoops, spirals and ties used in concrete deep foundation elements shall be terminated with seismic hooks, as defined in ACI 318, and shall be turned into the confined concrete core.

  1810.3.2.1.2 ACI 318 Equation (25.7.3.3). Where this chapter requires detailing of concrete deep foundation elements in accordance with Section 18.7.5.4 of ACI 318, compliance with Equation (25.7.3.3) of ACI 318 shall not be required.

  1810.3.2.2 Prestressing steel. Prestressing steel shall conform to ASTM A416.