Shear Wall Seismic Design

Shear walls are elements designed to take vertcal and in-plane horizontal forces, which produce bearing, shear and bending stresses.

The program performs the design of a concrete shear wall subjected to any combination of vertical and horizontal loads and bending moment, according to the ACI design criteria for structures in seismic zones (ACI 318-02 Chapter 21).

This program computes and checks the maximum shear stress in the wall and designs the shear reinforcement. In addition, the program designs, if necessary, the size and reinforcement of the boundary members.

Input Data

The required input data includes the total wall length and thickness, boundary member dimensions and reinforcement, materials' properties, and acting service loads, as shown in the figure below.

Example

As an example, consider the shear wall subjected to an overturning moment of 32945 k-ft, a vertical dead load of 3046 k, a vertical live load of 391 k and a horizontal force of 617 k, as shown below. Use f'c = 4 ksi and fy = 60 ksi.

Output

Once the data is entered, the program automatically computes the maximum stress and determines if boundary members are required or not, as per the ACI requirements. The shear design is performed, and the shear capacity checked.

In addition, a complete design of the boundary members, if needed, is carried out including the steel ratio and axial capacity check as well as the design of the confinement steel. The template related to this program with the example data is shown in the figure to the left..

Procedure

The program is based on the ACI 318-02 methodology. The shear design is performed so that the code requirements are satisfied, and the factored shear load is compared with the shear capacity.

When boundary members are required, the program calculates the force per boundary, either compression or tension, and compares it with the axial capacity.

Finally, the confinement reinforcement is designed to satisfy all code requirements.