Italics are used for text within Sections 1903A through 1905A of this code to indicate provisions that differ from ACI 318.
State of California amendments in these sections are shown in italics and underlined.
The scope of application of Chapter 19A is as follows:
- Structures regulated by the Division of the State Architect-Structural Safety (DSA-SS), which include those applications listed in Section 188.8.131.52. These applications include public elementary and secondary schools, community colleges and state-owned or state-leased essential services buildings.
DSA-SS and OSHPD adopt this chapter and all amendments.
Exception: Amendments adopted by only one agency appear in this chapter preceded with the appropriate acronym of the adopting agency, as follows:
- [DSA-SS] For applications listed in Section 184.108.40.206
- [OSHPD 1] – For applications listed in Section 1.10.1.
- [OSHPD 4] – For applications listed in Section 1.10.4.
The construction documents for structural concrete construction shall include:
- The specified compressive strength of concrete at the stated ages or stages of construction for which each concrete element is designed.
- The specified strength or grade of reinforcement.
- The size and location of structural elements, reinforcement and anchors.
- Provision for dimensional changes resulting from creep, shrinkage and temperature.
- The magnitude and location of prestressing forces.
- Anchorage length of reinforcement and location and length of lap splices.
- Type and location of mechanical and welded splices of reinforcement.
- Details and location of contraction or isolation joints specified for plain concrete.
- Minimum concrete compressive strength at time of posttensioning.
- Stressing sequence for posttensioning tendons.
- For structures assigned to Seismic Design Category D, E or F, a statement if slab on grade is designed as a structural diaphragm.
- Openings larger than 12 inches (305 mm) in any dimension shall be detailed on the structural drawings.
Materials used to produce concrete, concrete itself and testing thereof shall comply with the applicable standards listed in ACI 318.
Exception: The following standards as referenced in Chapter 35 shall be permitted to be used.
- ASTM C150
- ASTM C595
- ASTM C1157
Glass fiber-reinforced concrete (GFRC) and the materials used in such concrete shall be in accordance with the PCI MNL 128 standard.
Insulating concrete form material used for forming flat concrete walls shall conform to ASTM E2634. [OSHPD 1 & 4] Not Permitted by OSHPD.
Modify ACI 318 Section 220.127.116.11.1(a).(1) as follows:
(1) Normal weight aggregate: Aggregate shall be non-reactive as determined by one of the methods in ASTM C33 Appendix XI: Methods for Evaluating Potential for Deleterious Expansion Due to Alkali Reactivity of an Aggregate. Aggregates deemed to be deleterious or potentially deleterious may be used with the addition of a material that has been shown to prevent harmful expansion in accordance with Appendix XI of ASTM C33, when approved by the building official.
Modify ACI 318 Section 18.104.22.168(b) and Table 22.214.171.124(b) as follows:
The maximum percentage of pozzolans, including fly ash and silica fume, and slag cement in concrete assigned to all exposure categories shall be in accordance with Table 126.96.36.199(b) and Section 188.8.131.52(b) Items (1) and (2).
Where pozzolans are used as cementitous materials, duration for minimum specified compressive strength of concrete (f’c) that exceeds 28 days shall be considered an alternative system.
Modify ACI 318 Section 184.108.40.206(b) by adding the following:
Shop fusion welded stirrup/tie cage (or spiral assemblies) consisting of low-alloy steel reinforcing stirrups/ties conforming to ASTM A706 and longitudinal holding wires, conforming to ASTM A1064 shall be permitted. The fusion welds shall be made by machines using electric resistance welds. Tack welding of primary reinforcing bars together or to stirrups/ties is not permitted. Fusion welding of holding wires is not permitted on any portion of a reinforcing bar that is or will be bent in accordance with ACI 318 Section 25.3.
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 con crete 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.
Modify ACI 318, Section 220.127.116.11 by adding the following:
Where prestressed concrete elements are restrained from movement, an analysis of the stresses in the pre-stressed elements and loads in the adjoining structural system induced by the above-described effects shall be made in accordance with PCI Design Handbook.
Modify ACI 318 Section 18.104.22.168 by adding the following:
For prestressed concrete members with recessed or dapped ends, an analysis of the connections shall be made in accordance with procedures given in PCI Design Handbook.
Modify ACI 318, Section 22.214.171.124 by adding the following:
This section shall not be used for members that resist seismic loads, except that reinforcement provided for foundation elements for one-story wood-frame or one-story light steel buildings need not be more than one-third greater than that required by analysis for all loading conditions.
Replace ACI 318, Section 126.96.36.199 as follows:
188.8.131.52 – Walls shall be anchored to intersecting elements such as floors or roofs; or to columns, pilasters, buttresses, of intersecting walls and footings with reinforcement at least equivalent to No. 4 bars at 12 inches (305 mm) on center for each layer of reinforcement.
Add Section 11.7.6 to ACI 318.1 as follows:
11.7.6 – Reinforcement. Perimeters of precast walls shall be reinforced continuously with a minimum of one No. 5 bar extending the full height and width of the wall panel. Where wall panels do not connect to columns or other wall panels to develop at least 75 percent of the horizontal wall steel as noted below, vertical perimeter bars shall be retained by hooked wall bars
A continuous tie or bond beam shall be provided at the roof line either as a part of the roof structure or part of the wall panels as described in the next paragraph below. This tie may be designed as the edge member of the roof diaphragm but, in any case, shall not be less than equivalent to two No. 6 bars continuous. A continuous tie equivalent to two No. 5 bars minimum shall also be provided either in the footing or with an enlarged section of the floor slab.
Wall panels of shear wall buildings shall be connected to columns or to each other in such a manner as to develop at least 75 percent of the horizontal wall steel. No more than half of this continuous horizontal reinforcing shall be concentrated in bond or tie beams at the top and bottom of the walls and at points of intermediate lateral support. If possible, cast-in-place joints with reinforcing bars extending from the panels into the joint a sufficient distance to meet the splice requirements of ACI 318, Section 25.5.2, for Class A shall be used. The reinforcing bars or welded tie details shall not be spaced over eight times the wall thickness vertically nor fewer than four used in the wall panel height. Where wall panels are designed for their respective overturning forces, the panel connections need not comply with the requirements of this paragraph.
Modify ACI 318 by adding Section 11.9 as follows:
11.9 – Foundation walls. Horizontal reinforcing of concrete foundation walls for wood-frame or light-steel buildings shall consist of the equivalent of not less than one No. 5 bar located at the top and bottom of the wall. Where such walls exceed 3 feet (914 mm) in height, intermediate horizontal reinforcing shall be provided at spacing not to exceed 2 feet (610 mm) on center. Minimum vertical reinforcing shall consist of No. 3 bars at 24 inches (610 mm) on center.
Where concrete foundation walls or curbs extend above the floor line and support wood-frame or light-steel exterior, bearing or shear walls, they shall be doweled to the foundation wall below with a minimum of No. 3 bars at 24 inches (610 mm) on center. Where the height of the wall above the floor line exceeds 18 inches (457 mm), the wall above and below the floor line shall meet the requirements of ACI 318, Section 11.6 and 11.7.
Add Section 184.108.40.206 to ACI 318 as follows:
220.127.116.11 – At least two No. 5 bars in diaphragms having two layers of reinforcement in both directions and one No. 5 bar in diaphragms having a single layer of reinforcement in both directions shall be provided around openings larger than 12 inches in any dimension in addition to the minimum reinforcement required by Section 12.6.
Modify ACI 318, Sections 18.104.22.168.2, 22.214.171.124.3(d) and 126.96.36.199.2, to read as follows:
188.8.131.52.2 – Where the tensile component of the strength-level earthquake force applied to anchors exceeds 20 percent of the total factored anchor tensile force associated with the same load combination, anchors and their attachments shall be designed in accordance with 184.108.40.206.3. The anchor design tensile strength shall be determined in accordance with Section 220.127.116.11.4.
Exception: Anchors designed to resist wall out-of-plane forces with design strengths equal to or greater than the force determined in accordance with ASCE 7, Equation 12.11-1 or 12.14-10, and Section 1604A.8.2 of this code shall be deemed to satisfy Section 18.104.22.168.3(d).
22.214.171.124.3(d) – The anchor or group of anchors shall be designed for the maximum tension obtained from design load combinations that include E, with E increased by Ω0. The anchor design tensile strength shall be calculated from 126.96.36.199.4.
188.8.131.52.2 – Where the shear component of the strength-level earthquake force applied to anchors exceeds 20 percent of the total factored anchor shear force associated with the same load combination, anchors and their attachments shall be designed in accordance with 184.108.40.206.3. The anchor design shear strength for resisting earthquake forces shall be determined in accordance with 17.5.
- 1.1. The allowable in-plane shear strength of the anchor is determined in accordance with AWC NDS Table 11E for lateral design values parallel to grain.
- 1.2. The maximum anchor nominal diameter is 5/8 inch (16 mm).
- 1.3. Anchor bolts are embedded into concrete a minimum of 7 inches (178 mm).
- 1.4. Anchor bolts are located a minimum of 13/4 inches (45 mm) from the edge of the concrete parallel to the length of the wood sill plate.
- 1.5. Anchor bolts are located a minimum of 15 anchor diameters from the edge of the concrete perpendicular to the length of the wood sill plate.
- 1.6. The sill plate is 2-inch or 3-inch nominal thickness.
- 2.1. The maximum anchor nominal diameter is 5/8 inch (16 mm).
- 2.2. Anchors are embedded into concrete a minimum of 7 inches (178 mm).
- 2.3. Anchors are located a minimum of 13/4 inches (45 mm) from the edge of the concrete parallel to the length of the track.
- 2.4. Anchors are located a minimum of 15 anchor diameters from the edge of the concrete perpendicular to the length of the track.
- 2.5. The track is 33 to 68 mil designation thickness.
- In light-frame construction, bearing or non-bearing walls, shear strength of concrete anchors less than or equal to 1 inch (16 mm) in diameter of sill plate or track to foundation or foundation stem wall need not satisfy 220.127.116.11.3 (a) through (c) when the design strength of the anchors is determined in accordance with 18.104.22.168(c).
Modify ACI 318, Table 22.214.171.124 as follows:
For concrete designed and constructed in accordance with this chapter, f ’c, shall not be less than 3,000 psi (20.7 MPa). Reinforced normal weight concrete with specified compressive strength higher than 8,000 psi (55 MPa) shall require prior approval of structural design method and acceptance criteria by the enforcement agency.
Modify ACI 318, Section 18.5, by replacing Section 126.96.36.199, adding new Section 188.8.131.52 and renumbering existing Sections 184.108.40.206 and 220.127.116.11 to become 18.104.22.168 and 22.214.171.124, respectively:
126.96.36.199 – In connections between wall panels, yielding shall be restricted to steel elements or reinforcement. In connections between wall panels and the foundation, they shall be designed per Section 1616A.1.16.
188.8.131.52 – Connections that are designed to yield shall be capable of maintaining 80 percent of their design strength at deformation induced by the design displacement or shall use type 2 mechanical splices.
184.108.40.206 – Elements of the connection that are not designed to yeild shall develop at least 1.5 Sy.
220.127.116.11 – In structures assigned to SDC D, E or F, wall piers shall be designed in accordance with 18.10.8 or 18.14 in ACI 318.
Modify ACI 318, Section 18.104.22.168 by adding the following:
(c) Where boundary members are not required by ACI 318 Section 22.214.171.124 or 126.96.36.199 minimum reinforcement parallel to the edges of all structural walls and the boundaries of all openings shall consist of twice the cross-sectional area of the minimum shear reinforcement required per lineal foot of wall. Horizontal extent of boundary element shall be in accordance with ACI 318 Section 188.8.131.52 (a), (b) and (c).
Add Section 184.108.40.206 to ACI 318 as follows:
220.127.116.11 – Collector and boundary elements in topping slabs placed over precast floor and roof elements shall not be less than 3 inches (76 mm) or 6 db thick, where db is the diameter of the largest reinforcement in the topping slab.
Modify ACI 318, Section 18.104.22.168, to read as follows:
22.214.171.124 – Foundations resisting earthquake-induced forces or transferring earthquake-induced forces between a structure and ground shall comply with the requirements of 18.13 and other applicable provisions of ACI 318 unless modified by Chapter 18A of the California Building Code.
Replace Table 21.2.2 as follows:
STRENGTH REDUCTION FACTOR Φ FOR MOMENT, AXIAL FORCE, OR COMBINED MOMENT AND AXIAL FORCE
|NET TENSILE STRAIN εt||CLASSIFICATION||Φ|
|Type of transverse reinforcement|
|Spirals conforming to 25.7.3||Other|
|εt ≤ εty||Compression-controlled||0.75||(a)||0.65||(b)|
|εty < εt < 0.005||Transition1,2||(c)||(d)|
|εt ≥ 0.005||Tension-controlled3||0.9||(e)||0.9||(f)|
Add Section 126.96.36.199 to ACI 318 as follows:
188.8.131.52 – Span to depth ratio. Prestressed Beam and Slab Span to depth ratios for continuous prestressed concrete members shall not exceed the following, except when calculations of deflections and vibration effects prove that greater values may be used without adverse effects:
- Beams ......................................30
- One-way slabs .........................40
- Two-way floor slabs ................40
- Two-way roof slabs .................44
These ratios should be decreased for special conditions such as heavy loads and simple spans.
Maximum deflection criteria shall be in accordance with ACI 318 Section 24.2.2.
Replace ACI 318 Section 184.108.40.206(a) by the following:
220.127.116.11(a) Samples for strength tests of each class of concrete placed each day shall be taken not less than once a day, or not less than once for each 50 cubic yards (345 m3) of concrete, or not less than once for each 2,000 square feet (186 m2) of surface area for slabs or walls. Additional samples for seven-day compressive strength tests shall be taken for each class of concrete at the beginning of the concrete work or whenever the mix or aggregate is changed.
Not permitted by OSHPD and DSA-SS
The thickness of concrete floor slabs supported directly on the ground shall not be less than 31/2 inches (89 mm). A 6-mil (0.006 inch; 0.15 mm) polyethylene vapor retarder with joints lapped not less than 6 inches (152 mm) shall be placed between the base course or subgrade and the concrete floor slab, or other approved equivalent methods or materials shall be used to retard vapor transmission through the floor slab.
Exception: A vapor retarder is not required:
- For detached structures accessory to occupancies in Group R-3, such as garages, utility buildings or other unheated facilities.
- For unheated storage rooms having an area of less than 70 square feet (6.5 m2) and carports attached to occupancies in Group R-3.
- For buildings of other occupancies where migration of moisture through the slab from below will not be detrimental to the intended occupancy of the building.
- For driveways, walks, patios and other flatwork that will not be enclosed at a later date.
- Where approved based on local site conditions.
Shotcrete is mortar or concrete that is pneumatically projected at high velocity onto a surface. Except as specified in this section, shotcrete shall conform to the requirements of this chapter for reinforced concrete and the provisions of ACI 506. The specified compressive strength of shotcrete shall not be less than 3,000 psi (20.69 MPa).
[DSA-SS] Exception: The reference to ACI 506 shall be to ACI 506.2, unless otherwise approved by the enforcing agent. The specified compressive strength of structural shotcrete shall not be less than 4,000 psi (27.58 MPa) unless specifically approved by the enforcing agent.
Concrete or masonry to receive shotcrete shall have the entire surface thoroughly cleaned and roughened by sand blasting, and just prior to receiving shotcrete, shall be thoroughly cleaned of all debris, dirt and dust. Concrete and masonry shall be wetted before shotcrete is deposited, but not so wet as to overcome suction. Sand for sand blasting shall be clean, sharp and uniform in size, with no particles that will pass a 50-mesh screen. [DSA-SS] Cleaning and roughening provisions of ACI 506.2, Section 2.4.2, may alternatively be permitted.
Coarse aggregate, if used, shall not exceed 3/4 inch (19.1 mm).
GRADING LIMITS FOR COMBINED AGGREGATES
U.S. STANDARD SQUARE MESH
|PERCENT BY WEIGHT PASSING INDIVIDUAL SIEVES|
|Grading No. 1||Grading No. 2|
|3/4 in. (19 mm)||—||—|
|1/2 in. (12 mm)||—||100|
|3/8 in. (10 mm)||100||90 to 100|
|No. 4 (4.75 mm)||95 to 100||70 to 85|
|No. 8 (2.4 mm)||80 to 98||50 to 70|
|No. 16 (1.2 mm)||50 to 85||35 to 55|
|No. 30 (600 µm)||25 to 60||20 to 35|
|No. 50 (300 µm)||10 to 30||8 to 20|
|No. 100 (150 µm)||2 to 10||2 to 10|
When No. 5 or smaller bars are used, there shall be a minimum clearance between parallel reinforcement bars of 21/2 inches (64 mm). When bars larger than No. 5 are permitted, there shall be a minimum clearance between parallel bars equal to six diameters of the bars used. When two curtains of steel are provided, the curtain nearer the nozzle shall have a minimum spacing equal to 12 bar diameters and the remaining curtain shall have a minimum spacing of six bar diameters.
Exception: Subject to the approval of the building official, required clearances shall be reduced where it is demonstrated by preconstruction tests that adequate encasement of the bars used in the design will be achieved.
Except where permitted herein, unfinished work shall not be allowed to stand for more than 30 minutes unless edges are sloped to a thin edge. For structural elements that will be under compression and for construction joints shown on the approved construction documents, square joints are permitted. Before placing additional material adjacent to previously applied work, sloping and square edges shall be cleaned and wetted.
The film of laitance which forms on the surface of the shotcrete shall be removed within approximately two hours after application by brushing with a stiff broom. If this film is not removed within two hours, it shall be removed by thorough wire brushing or sand blasting. Construction joints over eight hours old shall be thoroughly cleaned with air and water prior to receiving shotcrete.
Forms for shotcrete shall be substantial and rigid. Forms shall be built and placed so as to permit the escape of air and rebound.
Adequate ground wires, which are to be used as screeds, shall be placed to establish the thickness, surface planes and form of the shotcrete work. All surfaces shall be rodded to these wires.
Shotcrete shall be placed in accordance with ACI 506.
The concrete supplier shall furnish to the enforcement agency certification that the cement proposed for use on the project has been manufactured and tested in compliance with the requirements of ASTM C150 for portland cement and ASTM C595 or ASTM C1157 for blended hydraulic cement, whichever is applicable. When a mineral admixture or ground granulated blast-furnace slag is proposed for use, the concrete supplier shall furnish to the enforcement agency certification that they have been manufactured and tested in compliance with ASTM C618 or ASTM C989, whichever is applicable. The concrete producer shall provide copies of the cementitious material supplier's Certificate of Compliance that represents the materials used by date of shipment for concrete. Cementitious materials without Certification of Compliance shall not be used.
Samples shall be taken from bundles as delivered from the mill, with the bundles identified as to heat number and the accompanying mill certificate. One tensile test and one bend test shall be made from a sample from each 10 tons (9080 kg) or fraction thereof of each size of reinforcing steel.
Where positive identification of the heat number cannot be made or where random samples are to be taken, one series of tests shall be made from each 2 1/2 tons (2270 kg) or fraction thereof of each size of reinforcing steel.
Tests of reinforcing bars may be waived by the structural engineer with the approval of the Building Official for one-story buildings or non-building structures provided they are identified in the construction documents and certified mill test reports are provided to the inspector of record for each shipment of such reinforcement.
All wires or bars of each size from each mill heat and all strands from each manufactured reel to be shipped to the site shall be assigned an individual lot number and shall be tagged in such a manner that each lot can be accurately identified at the jobsite. Each lot of tendon and anchorage assemblies and bar couplers to be installed shall be likewise identified.
The following samples of materials and tendons selected by the engineer or the designated testing laboratory from the prestressing steel at the plant or jobsite shall be furnished by the contractor and tested by an approved independent testing agency:
- For wire, strand or bars, 7-foot-long (2134 mm) samples shall be taken of the coil of wire or strand reel or rods. A minimum of one random sample per 5,000 pounds (2270 kg) of each heat or lot used on the job shall be selected.
- If the prestressing tendon is a bar, one 7-foot (2134 mm) length complete with one end anchorage shall be furnished and, in addition, if couplers are to be used with the bar, two 4-foot (1219 mm) lengths of bar fabricated to fit and equipped with one coupler shall be furnished.
- Mill tests of materials used for end anchorages shall be furnished. In addition, at least one Brinnell hardness test shall be made of each thickness of bearing plate.
Cores of the completed composite concrete construction shall be taken to demonstrate the shear strength along the contact surfaces. The cores shall be tested when the cast-in-place concrete is approximately 28 days old and shall be tested by a shear loading parallel to the joint between the precast concrete and the cast-in-place concrete. The minimum unit shear strength of the contact surface area of the core shall not be less than 100 psi (689 kPa).
At least one core shall be taken from each building for each 5,000 square feet (465m2) of area of composite concrete construction and not less than three cores shall be taken from each project. The architect or structural engineer in responsible charge of the project or his or her representative shall designate the location for sampling.
When post-installed anchors are used in lieu of cast-in place bolts, the installation verification test loads, frequency, and acceptance criteria shall be in accordance with this section.
Test loads or torques and acceptance criteria shall be shown on the construction documents.
If any anchor fails testing, all anchors of the same type shall be tested, which are installed by the same trade, not previously tested until twenty (20) consecutive anchors pass, then resume the initial test frequency.
The test procedure shall be as permitted by an approved evaluation report using criteria adopted in this code. All post-installed anchors shall be tension tested.
Exception: [OSHPD 1 & 4] Torque-controlled post-installed anchors shall be permitted to be tested using torque based on an approved test report using criteria adopted in this code.
Exception [DSA-SS]: Torque-controlled post-installed anchors and screw type anchors shall be permitted to be tested using torque based on an approved test report using criteria adopted in this code.
Alternatively, manufacturer's recommendation for testing may be approved by the enforcement agency, based on an approved test report using criteria adopted in this code.
When post-installed anchors are used for sill plate bolting applications, 10 percent of the anchors shall be tested.
When post-installed anchors are used for other structural applications, all such anchors shall be tested.
When post-installed anchors are used for nonstructural components, such as equipment anchorage, 50 percent or alternate bolts in a group, including at least one-half the anchors in each group, shall be tested.
The testing of the post-installed anchors shall be done in the presence of the special inspector and a report of the test results shall be submitted to the enforcement agency.
- Undercut anchors that allow visual confirmation of full set shall not require testing.
- Where the factored design tension on anchors is less than 100 lbs and those anchors are clearly noted on the approved construction documents, only 10 percent of those anchors shall be tested.
- Testing of shear dowels across cold joints in slabs on grade, where the slab is not part of the lateral force-resisting system shall not be required.
- Testing is not required for power actuated fasteners used to attach tracks of interior non-shear wall partitions for shear only, where there are at least three fasteners per segment of track.
Required test loads shall be determined by one of the following methods:
- The manufacturer's recommended installation torque based on an approved evaluation report using criteria adopted in this code.
Acceptance criteria for post-installed anchors shall be based on an approved evaluation report using criteria adopted in this code. Field tests shall satisfy the following minimum requirements.
The structural use of existing concrete with a core strength less than 1,500 psi (10.3MPa) is not permitted in rehabilitation work.
For existing concrete structures, sufficient cores shall be taken at representative locations throughout the structure, as designated by the architect or structural engineer, so that knowledge will be had of the in-place strength of the concrete. At least three cores shall be taken from each building for each 4,000 square feet (372 m2) of floor area, or fraction thereof. Cores shall be at least 4 inches (102 mm) in diameter. Cores as small as 2.75 inches (70 mm) in diameter may be allowed by the enforcement agency when reinforcement is closely spaced and the coarse aggregate does not exceed 3/4 inch (19 mm).
Crack repair of concrete and masonry member by epoxy injection, shall conform to all requirements of ACI 503.7.
Design and construction of externally bonded FRP systems for strengthening concrete structures shall be in accordance with ACI 440.2R.
- Near-Surface Mounted (NSM) FRP bars shall not be permitted.
- Strengthening of shear walls and diaphragms (including chords and collectors) shall be considered as an alternative system.
Design capacities, reliability, serviceability of FRP materials shall be permitted to be established in accordance with ICC-ES AC 125. Minimum inspection requirements of FRP composite systems shall be in accordance with ICC-ES AC 178.