盐冻条件下四氟滑板橡胶支座轴压力学性能研究

Compression Tests of PTFE Slide Rubber Bearings under Salt Freezing Cycle Condition

四氟滑板橡胶支座易受外界气候影响的影响，为研究四氟滑板橡胶支座经过盐冻处理后的承载力变化情况，采用标准冻融箱和质量分数为3．5％的NaCl溶液对四氟滑板橡胶支座分别进行20、40、60、80和100天盐冻处理，并进行轴压力学性能研究。通过对比分析盐冻处理对承载力、极限抗压强度、竖向刚度、弹性模量等性能的影响。在加载过程中，四氟滑板橡胶支座一般在上侧内陷，下侧鼓起，四个角部有翘曲，四个侧面具有凸起，而盐冻处理后的试件比标准试件更易发生脆性破坏，且钢板外露、裂缝等破坏现象更严重。四氟滑板橡胶支座的抗剪承载力、极限抗剪强度、水平等效刚度、抗剪弹性模量都随盐冻时间增加而降低。采用最小二乘法得出50年抗压强度的衰减曲线和衰减公式，其变化趋势基本符合幂函数规律。

Effects of PTFE slide rubber bearings support vulnerable to external climate impact, for the study of PTFE slide rubber bearings capacity changes after salt freezing, using standard freeze-thaw box and the mass fraction of 3.5% NaCl solution of PTFE slide rubber bearings are respectively 20, 40, 60, 80 and 100 days of salt freezing treatment, and axial compressive performance study. Through the comparative analysis of influence of salt freezing treatment on bearing capacity, ultimate strength, stiffness, elastic modulus and other properties. In the process of loading, PTFE slide rubber bearings in the side of invagination, the other side up, four comers with warping, four side has a convex, But salt freezing treatment of the specimens than standard specimens are more susceptible to brittle failure, and plate exposure, cracks and other damage phenomenon more serious. Shear strength, shear strength, horizontal stiffness, and shear modulus of elasticity with the salt freezing time decrease with the increase of PTFE slide rubber bearings support. Attenuation curve by the least square method those 50 years of compressive strength and attenuation formula, the trend is basically accord with power function law.