冻融条件下公路桥梁板式圆形氯丁橡胶支座力学性能试验

MECHANICAL TESTS OF CIRCULAR PLAIN CHLOROPRENE RUBBER BEARINGS OF HIGHWAY BRIDGE UNDER FREEZE-THAW CYCLE CONDITION

公路桥梁橡胶支座比建筑橡胶支座更容易受到气候的影响,为了研究公路桥梁圆形氯丁橡胶支座在冻融循环后的力学性能,将圆形氯丁橡胶支座放入标准冻融试验箱中处理100次,而后对其进行轴心受压和抗剪试验,与标准试件进行对比分析,研究承载力、极限抗压和抗剪强度、竖向刚度、水平等效刚度、弹性模量等各项性能指标的变化。结果表明,圆形氯丁橡胶支座经过冻融循环处理,更易发生脆性破坏,破坏现象较标准试件更为严重。随着冻融程度的加深,圆形氯丁橡胶支座的极限承载力、极限抗压及抗剪强度、抗压及抗剪弹性模量都逐渐降低,整体稳定性变差。

The impact of climate is more serious to highway bridge rubber bearings than to building rubber bearings,in order to study the changes of capacity of circular plain chloroprene rubber bearings of highway bridge under freezethaw cycle condition,the circular plain chloroprene rubber bearings were processed for 100 times by freeze-thaw cycle in the standard freeze-thaw chamber,then the axial compression and shear tests were carried out,and compared with the standard test pieces,and the changes of the performance indicators of the bearing capacity,the ultimate compressive strength and shear strength,vertical stiffness,horizontal equivalent stiffness,and elastic modulus were studied.The results showed that,the circular plain chloroprene rubber bearings were more prone to brittle failures after the freeze-thaw cycle,the damages were more serious than the standard test pieces.With the deepening of the degree of freezing and thawing,the ultimate bearing capacity,ultimate compressive strength and shear strength,compressive elastic modulus and shear elastic modulus of the circular plain chloroprene rubber bearings decreased,the overall stability had become worse.