摘要
为改善已有灌浆套筒施工的便利性,提出了一种新型套筒约束浆锚搭接接头,研究了该接头的力学性能.进行了不同搭接长度下16个该搭接接头的拉伸试验,研究了接头的破坏形态、力-位移曲线、承载力、延性、钢筋应变、套筒环向应变等,并基于试验数据及平截面假定对套筒截面的内力进行分析,解释了随搭接长度变化套筒环向(拉、压)应变的变化过程.由于套筒的约束,接头的搭接长度大大减小;试验中套筒的偏转导致试件的刚度、延性小于对应钢筋的刚度、延性;搭接接头套筒中部拉力比对接接头小,对套筒材料抗拉性能要求低,搭接接头钢筋通过灌浆料传递到套筒上的剪应力比对接接头小,对套筒与灌浆料的界面粘结性能要求低.当套筒长度短时,钢筋与灌浆料间出现滑移,使得套筒中部钢筋的拉力变大,套筒与灌浆料合力为压力,反之,套筒与灌浆料合力为拉力;随着搭接长度的增加,加载过程中套筒中部近钢筋侧环向最大压应变增大;极限荷载时,随着搭接长度增加,套筒各测点环向拉应变总体呈降低的趋势.
To improve the convenience of grouting sleeve construction and explore its mechanical properties,a newly grouted sleeve lapping connector that two overlapped bars were placed, clinging to the wall of a hollow cylindrical standard steel pipe and anchored by high strength grout,was put forward. 16 specimens varied in lap length were tested under tensile load. The failure mode, load displacement curve, ductility and hoop strain of sleeve were discussed.Based on the experimental results and plane section assumption, mechanical property analysis of grouted sleeve lapping connector were conducted. The relationship of sleeve hoop strain varying with lap length was studied.The lapping length is greatly reduced due to sleeve constraint.Because of sleeve deflection, the rigidity and ductility of the specimen are smaller than that of the corresponding steel.The tension in the middle of the lapping connector and the shear transferred through grout to sleeve are smaller than that in butting connector, so there is a lower requirement in anti-pull property of sleeve and bond property between grout and sleeve.When the sleeve length is short,slip in the interface of steel and grout increases the tension of middle steel, thus the resultant force of the sleeve and grout is pressure, on the contrary, the resultant force is tensile force. As the lap length increases, the maximum hoop compressive strain increases in the middle of the sleeve during the loading process. At ultimate load, as the lap length increases, the hoop tensile strain of the sleeve decreases.
出处
《湖南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2017年第9期82-91,共10页
Journal of Hunan University:Natural Sciences
基金
国家自然科学基金资助项目(51322803)~~
关键词
灌浆料膨胀
套筒环向压应变
搭接与对接
套筒偏转
微量滑移
expansion of grouting material
hoop strain of the sleeve
lapping and butting connector
deflection of sleeve
microslip
