Specimen W4 with Cut-off Longitudinal Reinforcement in the Web and a Repetition of 6 for Each Drift Target

The main objective of this study is to test the hypothesis that discontinuities in the longitudinal web reinforcement of a structural wall will cause strain concentration in the longitudinal boundary reinforcement. This strain concentration will affect the seismic response of the structural wall. To achieve this objective, six small-scale structural walls with nominally identical cross sections were built and tested by applying displacement reversals. These specimens were divided into three pairs with two test variables: 1) The continuity of longitudinal reinforcement in the web; 2) Number of cycles for a given drift target.

Specimen W4 had cut-off longitudinal reinforcement in the web. It was subjected to lateral displacement reversals ranging from 0.25% to 5% of the specimen height. Each displacement target was repeated six times.

Specimen W4 failed in the same manner as specimen W3, except that specimen W4 lost concrete cover by the end of the first cycle at a drift ratio of 4.0%. The longitudinal bars in the north boundary element were observed to have buckled during the second cycle at a drift ratio of 4.0%.

Crack maps, photos and detailed analysis of this specimen are given in the final report.