为研究预制UHPC(Ultra High Performance Concrete,UHPC)节段梁间胶接缝在剪切荷载下的力学性能,开展了一组UHPC单键齿胶接缝和七组UHPC多键齿胶接缝抗剪性能试验,考虑键齿数量,键齿形式(高深比),胶层厚度和正应力水平对剪切荷载下UHPC多键齿胶接缝破坏过程,破坏模式和承载能力的影响.结果表明:UHPC多键齿胶接缝均在极限荷载的0.6～0.7的范围内出现开裂,键齿数量、正应力水平和键齿形式(高深比)对UHPC多键齿胶接缝抗剪性能的影响较大,增加键齿数量,提高正应力水平,采用高深比较大的键齿形式均能在不同程度上提高UHPC多键齿胶接缝的抗剪承载力和延性;胶层厚度对UHPC多键齿胶接缝抗剪性能的提升影响较小;考虑键齿折减效应的计算公式能够较为准确的预测UHPC多键齿胶接缝的抗剪承载力.
Experimental Study on Shear Behavior of Key Tooth Adhesive Joints of UHPC Segmental Beam
To study the mechanical properties of adhesive joints between prefabricated UHPC segmental beams under shear load,the shear behaviors of one group of UHPC single-key tooth adhesive joints and seven groups of UHPC multi-key tooth adhesive joints are tested.The effects of the number of key teeth,the form of key teeth(height-to-depth ratio),the thickness of adhesive layer and the normal stress level on the failure process,failure mode and bearing capacity of the UHPC multi-key adhesive joint under shear load are considered.The results show that the UHPC multi-key tooth adhesive joint cracks in the range of 0.6～0.7 of the ultimate load.The number of key teeth,the normal stress level and the form of key teeth(height-to-depth ratio)have the great influence on the shear behavior of UHPC multi-key toot adhesive joints.Increasing the number of keys,raising the normal stress level and choosing the form of key teeth with the larger height-to-depth ratio can improve the shear bearing capacity and ductility of UHPC multi-key tooth adhesive joints.The thickness of adhesive layer has little effect on the improvement of shear behavior of UHPC multi-key tooth adhesive joints.The calculation formula considering the deduction effect of key teeth can accurately predict the shear bearing capacity of UHPC multi-key tooth adhesive joints.
万方数据
维普
