Civil Engineering Reference
In-Depth Information
10.3.2 Low-rise Framed Shear Walls at NCREE
A low-rise shear wall (RLB) was tested under reversed cyclic horizontal loading at NCREE
(Zhong, 2005). Figure 10.9 shows the height, length, and thickness of the wall to be 1.4, 2.8
and 0.12 m, respectively. Other dimensions and reinforcements of the specimen are also given.
The compressive strength of the concrete was 36.0 MPa, and the yield stress of rebars in the
wall was 329 MPa. The steel ratio for the specimen is 0.48%. The end regions of the shear
wall RLB were provided with a 240
×
240 mm boundary element having longitudinal bars
and stirrups. Reversed cyclic horizontal loads were applied on the top of the shear wall. The
test procedure is controlled by the horizontal displacement at the top of the wall. Analysis of
the reversed cycle tests from this specimen was performed by program SCS.
The specimen was modeled using the finite element meshes, as shown in Figure 10.10.
The mesh was divided into three regions consisting of the web panel, the top beam and the
boundary elements. For simplification of the analyses, the foundation was omitted and the wall
was modeled fixed to the ground. The wall panel was modeled by 8 RCPlaneStress quadrilateral
elements. The top beam was modeled using four nonlinear beam-column elements and each
boundary element of the specimen was modeled using two nonlinear beam-column elements.
Each nonlinear beam-column element used to model the boundary elements was defined with
three control sections; and each section was discretized into 42 fibers. The configuration of
the section discretization is shown in Figure 10.11. The white cells represent the unconfined
concrete fibers (24 fibers), the gray cells represent the confined concrete fibers (10 fibers),
and the black cells represent the reinforcing steel fibers (8 fibers). The stress and strain of the
confined concrete was determined based on the modified Kent and Park model (Scott
et al
.,
1982). The horizontal loads were uniformly imposed as the nodal forces along the nodes of top
Figure 10.9
Dimensions and reinforcement of specimen RLB
