Chapter 16A Structural Design

California amendments by DSA and OSHPD

Division of the State Architect and
Office of Statewide Health Planning and Development

Updates, clarifications and revisions to ASCE 7 standards: Seismic ground motion values, response modification coefficient; Two-Stage Analysis Procedure; Horizontal and Vertical Irregularities for Seismic Design Categories; Foundation connections; Wall, Roof or Floor Hung Equipment; Provisions for piping and tubing systems.

1605A.2 Alternative allowable stress design load combinations

Added a variable load requirement for the alternative allowable stress design load combinations.

Table 1613A.2.3(1) and Table 1613A.2.3(2)

Amendment language in Site Class E (Table 1613.2.3(1) only) and footnote C to be consistent with ASCE 7-16 Supplement 3 as amended in CBC Chapter 35.

1617A.1.3 ASCE 7, Section 11.4

Modifications to ASCE 7 including an amendment added to adopt ASCE 7-16 Supplement 3 which updates various subsections in ASCE 7-16 Section 11.4 to the seismic ground motions values.

1617A.1.5 ASCE 7, Section 12.2.3, 12.2.3.1, and 12.2.3.2

Amended to incorporate the ballot change proposals related to combining of different lateral force resisting systems and the Two Stage Analysis Procedures that passed main committee ballot of ASCE 7-22. Some of these amendments will need to be deleted when ASCE 7-22 is adopted to avoid duplication.

1617A.1.10 ASCE 7, Section 12.3.3.1

Exception 2 added to address structures having a horizontal structural irregularity Type 1b of Table 12.3-1.

1617A.1.16 ASCE 7, Section 12.13.9.2

Clarification added that lateral building response including seismic load combinations do not need to be considered concurrently with differential settlements for shallow foundations on liquefiable sites, and to clarify that force demands due to differential settlements are not required to be additive to the seismic earthquake demands.

1617A.1.18 ASCE 7, Section 13.1.4

This section applying to different types of equipment is now being co-adopted by DSA with varying weight requirements. Wall, Roof or Floor Hung Equipment requirements added by both DSA and OSHPD.

1617A.1.27 and 1617A.1.28

Clarification added that minimum horizontal acceleration requirement is an allowable stress design load.