侵蚀条件下板式天然橡胶支座受力性能研究

发布时间：2018-04-22 20:48

本文选题：天然橡胶支座 + 极限抗压强度　；参考：《沈阳建筑大学》2014年硕士论文

【摘要】：板式天然橡胶支座由多层均匀分布的橡胶与钢板叠合而成,是公路桥梁重要的承力和抗震减振装置,近20年来在我国得以广泛应用,其质量优劣和工作应力直接影响着支座的作用、功能和桥梁结构的安全可靠度与使用寿命。根据调查发现,自产品标准JT/T4-93及相应规格系列颁布以来,几乎每条高速公路上的橡胶支座都有不同程度的劣化,使用寿命远远低于设计寿命,现在已发展到未通车的在建桥梁的板式橡胶支座安装后就大量损坏。影响质量的因素是多方面的,有施工质量方面的问题,也有支座生产厂家生产工艺的问题和选用原料(胶料、填充剂等)质量的问题,也有桥梁设计(包括支座的设计与选用)的问题。针对橡胶支座日益被广泛应用的趋势,其性能的优劣直接影响到我们的日常生活甚至生命财产安全。本文综合当今多种主要环境因素,从湿热环境、酸雨环境(包括硝酸型酸雨、硫酸型酸雨及硝硫混合型酸雨)、冻融环境、盐冻环境及热老化环境等,研究板式天然橡胶支座在各种环境因素单独影响下,其力学性能及耐久性的改变,从而改进橡胶支座的缺损状况评定方法,制定出新的技术状况评定标准,为日后公路桥梁橡胶支座的检验检测提供相关的依据。为研究板式天然橡胶支座在高温、潮湿的环境下能否按预定的要求起到其应有的效果,及力学性能的改变情况,设计将一批橡胶支座置于高低温交变湿热试验箱中,控制一定的温度与湿度,分别进行20天、40天、60天、80天和100天的处理,模拟自然界中南方高温潮湿环境及西北高温干燥环境对天然橡胶支座的影响。对经处理过的试件分别进行抗压与抗剪试验,从极限抗压强度、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方面研究其力学性能的变化。采用最小二乘法建立天然橡胶支座的衰减模型,推导出相应的拟合曲线及衰减函数,用于粗略估算环境因子对于橡胶支座力学性能的改变情况。为研究板式天然橡胶支座在酸雨环境下能否按预定的要求起到其应有的效果,及力学性能的改变情况,设计将一批橡胶支座浸泡于一定浓度(pH=4.5)的硝酸溶液、硫酸溶液和按1：1体积比配比的硝硫酸混合溶液中,分别进行20天、40天、60天、80天和100天的处理,模拟自然界中硝酸型酸雨、硫酸型酸雨及硝硫混合型酸雨环境对天然橡胶支座的影响。对经处理过的试件分别进行抗压与抗剪试验,从极限抗压强度、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方面研究其力学性能的变化。采用最小二乘法建立天然橡胶支座的衰减模型,推导出相应的拟合曲线及衰减函数,用于粗略估算环境因子对于橡胶支座力学性能的改变情况。为研究板式天然橡胶支座在冻融交替循环环境下能否按预定的要求起到其应有的效果,及力学性能的改变情况,设计将一批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次、50次、75次、100次和150次冻融循环处理,模拟自然界中我国北方大部分地区冬季冻融交替环境对天然橡胶支座的影响。对经处理过的试件分别进行抗压与抗剪试验,从极限抗压强度、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方面研究其力学性能的变化。采用最小二乘法建立天然橡胶支座的衰减模型,推导出相应的拟合曲线及衰减函数,用于粗略估算环境因子对于橡胶支座力学性能的改变情况。为研究板式天然橡胶支座在盐冻环境下能否按预定的要求起到其应有的效果,及力学性能的改变情况,设计将一批橡胶支座置于浓度为3%的NaCl溶液中浸泡,然后将其放置在高低温试验箱中进行冻融循环,分别进行20天、40天、60天、80天和100天的盐冻处理,模拟自然界中盐冻环境对天然橡胶支座的影响。对经处理过的试件分别进行抗压与抗剪试验,从极限抗压强度、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方面研究其力学性能的变化。采用最小二乘法建立天然橡胶支座的衰减模型,推导出相应的拟合曲线及衰减函数,用于粗略估算环境因子对于橡胶支座力学性能的改变情况。
[Abstract]:The plate type natural rubber bearing is made of laminated rubber and steel plate. It is an important load bearing and seismic vibration damping device for highway bridges. It has been widely used in China in the past 20 years. Its quality and working stress have a direct impact on the function of the support, the safety reliability and service life of the function and bridge structure. Now, since the product standard JT/T4-93 and the corresponding specification series are promulgated, almost every highway rubber bearing has different degrees of deterioration, the service life is far lower than the design life, and now it has developed to the large amount of damage after the plate type rubber bearing of the bridge is not opened. The factors affecting the quality are many aspects. The problem of the quality of the work quality, the problem of the production process of the supporting manufacturer and the quality of the selection of raw materials (glue material, filling agent, etc.), and the problem of bridge design (including the design and selection of the support). In view of the increasingly widely used trend of the rubber bearing, the quality of its sexual ability directly affects our daily life and even life. In this paper, a variety of major environmental factors, including wet and hot environment, acid rain environment (including nitric acid rain, acid rain and nitrate sulphur mixed acid rain), freezing and thawing environment, salt freezing environment and thermal aging environment, are used to study the mechanical properties and durability of the plate type natural rubber bearing under the influence of various environmental factors. To improve the evaluation method of the defect condition of the rubber bearing and establish a new standard of technical condition assessment for the inspection and inspection of the rubber bearing in the future highway bridge, it is necessary to study whether the plate type natural rubber bearing can have its due effect and the change of mechanical properties in the high temperature and damp environment. A batch of rubber bearing is placed in a high and low temperature alternating damp heat test box to control certain temperature and humidity for 20 days, 40 days, 60 days, 80 days and 100 days respectively, to simulate the effect of high temperature and humidity in the south of the world and the influence of the northwest high temperature drying environment on the natural rubber bearing. With the shear test, the change of mechanical properties is studied from the aspects of ultimate compressive strength, ultimate shear strength, compressive modulus of elasticity, shear modulus of elasticity, vertical stiffness and horizontal equivalent stiffness. The attenuation model of natural rubber bearing is established by least square method, and the fitting curve and attenuation function are derived for rough estimation of the environment. In order to study the change of mechanical properties of rubber bearing, in order to study whether or not the plate type natural rubber bearing can have its due effect in the acid rain environment, and the change of mechanical properties, a batch of rubber bearing is soaked in a certain concentration (pH=4.5) of nitric acid solution, sulphuric acid solution and the ratio of 1:1 volume ratio. In the mixed solution of sulfuric acid, the treatment of 20 days, 40 days, 60 days, 80 days and 100 days was carried out to simulate the effects of acid rain, acid rain and nitrate sulphur acid rain environment on natural rubber bearing in nature. The compression and shear tests were carried out on the treated specimens, from the ultimate compressive strength, the ultimate shear strength and the compression elasticity. The change of modulus, shear modulus, vertical stiffness and horizontal equivalent stiffness are studied. The least square method is used to establish the attenuation model of natural rubber bearing, and the corresponding fitting curve and attenuation function are derived, which can be used to estimate the change of the mechanical properties of rubber support by environmental factors. In the environment of freeze-thaw alternate cycle, can the natural rubber bearing have its due effect, and the change of mechanical properties. A batch of rubber bearing is put in a standard freezing thawing test box to control certain temperature and humidity, and 25, 50, 75, 100 and 150 cycles of freezing and thawing are treated respectively in the natural environment. The effect of freezing thawing alternate environment on natural rubber bearing in most parts of North China in winter. The compressive and shear tests were carried out on the treated specimens. The changes of mechanical properties were studied from the aspects of ultimate compressive strength, ultimate shear strength, compressive elastic modulus, shear modulus of elasticity, vertical stiffness and equal effect stiffness. The least square method is used to establish the attenuation model of natural rubber bearing, and the corresponding fitting curve and attenuation function are derived, which can be used to estimate the change of the mechanical properties of rubber bearing in a rough estimate. A batch of rubber bearings were placed in a NaCl solution with a concentration of 3%, and then placed in a high and low temperature test box for freezing and thawing cycles for 20 days, 40 days, 60 days, 80 days and 100 days, respectively, to simulate the effect of salt freezing environment on natural rubber bearing in nature. The change of mechanical properties is studied from extreme compressive strength, ultimate shear strength, compressive modulus of elasticity, shear modulus of elasticity, shear modulus of elasticity, vertical stiffness and horizontal equivalent stiffness. The attenuation model of natural rubber bearing is established by the least square method, and the corresponding fitting curve and attenuation function are derived, which is used for rough estimation of the ring. The influence of environmental factors on the mechanical properties of rubber bearings.

【学位授予单位】：沈阳建筑大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU352.12

【参考文献】