// CODE SNIPPET

# 1617.1.1.2 Maximum Seismic Load Effect, EM

JUMP TO FULL CODE CHAPTER
The maximum seismic load effect, Em, shall be used in the special seismic load combinations in Section 1605.4.

Where the effects of the seismic ground motion and gravity loads are additive, seismic load,

Where the effects of the seismic ground and gravity loads counteract, seismic load,

where

The term

Where allowable stress design methodologies are used with the special load combinations of Section 1605.4, design strengths are permitted to be determined using an allowable stress increase of 1.7 and a resistance factor, f, of 1.0. This increase shall not be combined with increases in allowable stresses or load combination reductions otherwise permitted by this code or the material reference standard except that combination with the duration of load increases in Chapter 23 is permitted.

Where the effects of the seismic ground motion and gravity loads are additive, seismic load,

*E*, for use in Equation 16-19, shall be defined by Equation 16-52.

_{m}
Em=

*ΩQ*+ 0.2_{E}*S*_{DS}D**(Equation 16-52)**Where the effects of the seismic ground and gravity loads counteract, seismic load,

*E*, for use in Equation 16-20, shall be defined by Equation 16-53.

_{m}
Em=

*ΩQ*- 0.2_{E}*S*_{DS}D**(Equation 16-53)**where

*E*,

*Q*,

_{E}*are as defined above and Ω*

_{SDS}*is the system over strength factor as given in Table 1617.6.2.*

_{0}The term

*need not exceed the maximum force that can be transferred to the element by the other elements of the lateral-force-resisting system.*

_{0}Q_{E}Where allowable stress design methodologies are used with the special load combinations of Section 1605.4, design strengths are permitted to be determined using an allowable stress increase of 1.7 and a resistance factor, f, of 1.0. This increase shall not be combined with increases in allowable stresses or load combination reductions otherwise permitted by this code or the material reference standard except that combination with the duration of load increases in Chapter 23 is permitted.

### Related Code Sections

1617.1.1.2 Structural Design, Maximum Seismic Load Effect, EM

The

*maximum**seismic**load**effect*,*Em*, shall be used in the special*seismic**load*combinations in Section 1605.4. Where the*effects*...
NYC Building Code 2008 > 16 Structural Design > 1617 Earthquake Loads — Minimum Designlateral Force and Related Effects > 1617.1 Seismic Load Effect E and EM > 1617.1.1 Seismic Load Effects, E and EM (For Use in the Simplified Analysis Procedure of Section 1617.5) > 1617.1.1.2 Maximum Seismic Load Effect, EM

1620.3.2 Structural Design, Direction of Seismic Load

for any column or wall that forms part of two or more intersecting

*seismic*-force-resisting systems and is subjected to axial*load*due ...
NYC Building Code 2008 > 16 Structural Design > 1620 Earthquake Loads — Design, Detailing Requirements and Structural Component Load Effects > 1620.3 Seismic Design Category C > 1620.3.2 Direction of Seismic Load

1605.4 Structural Design, Special Seismic Load Combinations

of the

*seismic*ground motion are additive to gravity forces and those calculated using Equation 16-20 when the*effects*of the*seismic*ground motion ...
NYC Building Code 2008 > 16 Structural Design > 1605 Load Combinations > 1605.4 Special Seismic Load Combinations

1614.5 Structural Design, Seismic and Wind

When the code-prescribed wind design produces greater

*effects*, the wind design shall govern, but detailing requirements and limitations ...
NYC Building Code 2008 > 16 Structural Design > 1614 Earthquake Loads — General > 1614.5 Seismic and Wind

1613.2 Structural Design, Definitions

) GROUND MOTION. The most severe earthquake

*effects*considered by this standard more specifically defined in the following two terms.*MAXIMUM*...