Seismic Analysis for Trapezoidal Shape House

[dgengineering]

Hi Everyone,

I am designing a trapezoidal shape house and I wanna know how to get the reaction on the inclined shear wall. If I assume earthquake hits from either x or y direction then it's easy to find the reaction on that shear wall using the angle. But what if the earthquake direction is in the inclined wall direction at 65 degrees? (see my sketch, line 6). How would you get the reaction?

Thank you so much

 

[HDStructural]

Couldn't you simplify the angled earthquake loads by converting the 65 degree angle to x and y components of it. sin(65) = 0.91, cos(65) = 0.42. For the angled earthquake, add together 91 percent of the N/S earthquake loads with 42% of the east/west earthquake loads for each wall section. Be careful with sign orientation for each wall force.

 

[dgengineering]

Yes, that makes sense. Thank you HD

 

[driftLimiter]

If the lateral element takes load from each direction you could consider combining the effects according to ASCE 7-16 12.5.3.1

 

[HTURKAK]

Definition of Nonparallel System Irregularity: Nonparallel system irregularity, defined to exist where vertical lateral force-resisting elements are not parallel to the major orthogonal axes of the seismic force-resisting system.

You diid not give info. regarding SDC . In case of SDC D, E, or F,
You are expected to model and analyze the SFRS 3D and follow Orthogonal Directional Combination Procedure and 30% rule .