Abstract：When reinforcing bridge structures, planting bars shall be the most commonly used enhancement measure of interface connection. In order to clarify the mechanical properties of the UHPC-reinforced stone masonry structure with bar planted interface, 30 UHPC-stone composite specimens were tested to study the effects of bar planting rate of interface, planting bar depth and planting bar spacing on the shear performance of UHPC-stone interface, and then the crack development and distribution and load-slip curve characteristics of the composite specimens under different planting parameters were analyzed. The results show that: (1) The failure modes of the UHPC-stone composite specimens without planting bars are all brittle failures, while the specimens with planting bar are mainly characterized by ductile failure modes with interface slippage and local stone splitting. The crack morphology on stone surface presents diagonal cracks. (2) When the bar planting rate is less than 0.29%, the interface shear strength and ductility of the composite specimens may increase step by step with the increase of the bar planting rate, and the shear strengths of specimens with the bar planting rate of 0.09%, 0.19% and 0.29% are 1.54 times, 1.98 times and 2.66 times that of the composite specimens without planting bars, respectively. However, when the planting bar rate increases continuously, the strength of UHPC-stone interface exhibits a decreasing trend. (3) The depth of the planting bars and the spacing of the planting bars have little effects on the interface shear strength of the composite specimen, but have a greater impact on the ductility of the UHPC-stone interface. (4) Based on the test results and finite element analysis, it is recommended that when UHPC is used to strengthen the stone masonry structure, the maximum anchorage length of the ribbed steel bar is 10 d (in which d is the nominal diameter of the steel bar), and the planting bar spacing of 50～100 mm shall be reasonable. In view of the factors such as safety and economy, it is recommended that the optimal planting bar rate for the interface between UHPC and stone is taken as 0.29%, while the thickness of the UHPC reinforcement layer should be 50 mm.
杨俊 陈瑞 张中亚 邹杨 周建庭 王蔚丞. 植筋参数对UHPC-石材界面抗剪性能的影响研究[J]. 土木工程学报, 2022, 55(6): 62-78.
Yang Jun Chen Rui Zhang Zhongya Zou Yang Zhou Jianting Wang Weicheng. Effects of planting bar parameters on the shear resistance of UHPC-stone interface. 土木工程学报, 2022, 55(6): 62-78.
