Abstract
In this study, the effects of the embedded depth of anchor, the unevenness of interface and the concrete strength were investigated as the fundamental research for the purpose of the clarification of shear slip behavior of the placing joint by outside seismic reinforcement. In this experiment, two embedded depths of anchor（the depths are 5d and 10d, in which d is a nominal diameter of anchor）, three unevenness of interface（the 凹凸 sizes are 0, 10 and 20mm）and two water-cement ratios of the reinforcing mortar（the water-cement ratios are 40 and 90％）were selected as shown in Table 1. The specimen as shown in Fig. 1 and the loading apparatus as shown in Fig. 3 were used in this experiment. The results obtained by the experiments can be summarized as follows：
1）The shear resistance of the placing joint reinforced by the anchor can be obtained as the sum of the dowel action by the anchor and the interlocking action caused by the uneven interface.
2）The shear carrying capacity increases with increasing the embedded depth of the anchor and the unevenness of interface of the placing joint, independently of the strength of reinforcing mortar.
3）In the case of the specimen with the flat interface and with the low strength of reinforcing mortar, the ductile load-slip relationship of placing joint can be obtained.
