冻融条件下板式天然橡胶支座力学性能试验研究

Testing study on mechanical performance of natural rubber plate bearing under the condition of freezing and thawing

以宁夏六盘山东毛高速公路桥梁工程为依托,通过室内试验,将一批板式天然橡胶支座置于标准冻融试验箱中,控制一定的温度与湿度,分别进行25,50,75,100,150次冻融循环处理,模拟宁夏高原地区冬季冻融交替环境对天然橡胶支座的影响.试验得到了其极限抗压强度、极限抗剪强度、抗压弹性模量、抗剪弹性模量、竖向刚度及水平等效刚度等力学性能方面的变化,并采用最小二乘法建立天然橡胶支座的衰减模型,推导出了相应的拟合曲线及衰减函数.

In order to simulate the effects of freeze-thaw alternative circumstance on natural rubber bearings during the winter of Ningxia plateau areas, laboratory test was adopted based on highway bridge engineering of Liupan Mountain in Ningxia Province. A batch of bearings were put into standard freeze-thaw test chamber, and 25, 50, 75, 100, 150 times of freeze-thaw cycling treatments were conducted seperatedly under certain temperature and humidity. Mechanical performance variations, such as ultimate compressive strength, ultimate shear strength, compressive elastic modulus, shear elastic modulus, and vertical and horizontal equivalent stiffness, were obtained in the test, then attenuation model of natural rubber bearing was established via adopting least square method. Finally, corresponding fitting curve and attenuation function were deduced.