Abstract：In order to investigate the seismic behavior of confined masonry walls strengthened with single high ductile concrete (HDC) layer, 4 confined masonry walls strengthened with single HDC layer and 4 confined masonry walls without being strengthened for comparison purpose were tested under the low-cycle repeated loading. The failure pattern, hysteretic characteristics and stiffness degradation of confined masonry walls strengthened with single HDC layer were studied. Test results show that the single HDC layer can provide effective constraint for the wall, significantly improve the lateral strength and the stiffness of the wall and delay the occurrence of cracks and degradation of stiffness; The strengthened specimens were characterized with high residual bearing capacities with damages mainly concentrated on the HDC layer; After being strengthened with single HDC layer, the contributions of the strength of the masonry mortar to the improvement of shear capacity of the confined masonry wall was not obvious. Based on test results, a formula of determining the shear capacity was proposed as design reference for confined masonry walls strengthened with single HDC layer. The predicted shear capacity according to the formula was close to but lower than the measured value.
