Study On Mechanical Properties Of Plain Chloroprene Rubber Bearings Under Erosion Condition

Neoprene bearing is composed of uniform thin plate and uniform distributed neoprene layer.It is an important seismic apparatus in structural for its high elasticity and higher deformation ability. In addition to having excellent physical properties of other material support,neoprenebear ings has the advantages that is replaceable, simple structure, buffer shock. But the neoprene bearings are used in external environment for a long time, all the physical properties will be damaged after corroded by the external environment.Neoprene bearings were used widely because of it has many advantages. So after the neoprene bearings were eroded by the external environment, many researchers pay a attention to the change rules of the mechanical propertie.Now, the earth has been pollutted seriously, the frequency of acid rain is more and more big, neoprene bearings will suffer serious acid corrosion,with an increasing number of cross-sea bridge and river acrossing, the mechanics performance of the neoprene bearing corroded by sea water and salt solution for long-term has great research significance. Neoprene bearing need a moderate temperature,and it has high requirements for mechanical property in the large change climate, the climate in most regions of China is usually cold winter hot summer. So study on the mechanical properties of Neoprene bearing has great significance. Research on rubber bearing has a lot at home and abroad, but research on neoprene bearing performance is relatively single. So, the systematically studied of neoprene bearings mechanical properties which under freeze-thaw cycle and hot corrosion, salt-freezing, acid nitric acid, nitric acid, hot and humid conditions offers references for the construction of highway Bridges in the future. The main content of the research are as follows:In order to study whether the neoprene bearing is achieving predetermined requirements in acid rain environment and the change of it's mechanical property, the specimen are immersed in a certain concentration of nitric acid, sulfuric acid solution and the 1:1 volume ratio of mixed solution of sulphate nitrate for 20,40,60,80 and 100d,then compressed axially and sheared horizontally. The changes of neoprene bearing mechanical properties can be studied from ultimate compressive strength, ultimate shearing strength, compressive elastic modulus, shearing elastic modulus, vertical stiffness, level equivalent stiffness etc. The attenuation model of neoprene bearings created by the least square method.In order to study the force performance change rules of the neoprene bearing under hot and humid corrosion condition. Specimens were putted in the high and low temperature alternating humid heat test box for 20d,40d,60d,80d,100d. then compressed axially and sheared horizontally. Its changes of the mechanical properties can be studied from ultimate compressive strength, ultimate shearing strength, compressive elastic modulus, shearing elastic modulus, vertical stiffness, level equivalent stiffness etc. The attenuation model of neoprene rubber bearings created by the least square method can be used to derived the fitting curve and the attenuation function.In order to study the force performance change rules of the neoprene bearing under hot corrosion condition. Specimens were putted in the constant temperature of drum wind drying oven for 20d,40d,60d,80d,100d. then compressed axially and sheared horizontally. Its changes of the mechanical properties can be studied from ultimate compressive strength, ultimate shearing strength, compressive elastic modulus, shearing elastic modulus, vertical stiffness, level equivalent stiffness etc. The attenuation model of neoprene rubber bearings created by the least square method can be used to derived the fitting curve and the attenuation function.In order to study the force performance change rules of the neoprene bearing under low temperature condition. Specimens were putted in the standard freeze-thaw test chamber for 20d,40d,60d,80d,100d. then compressed axially and sheared horizontally. Its changes of the mechanical properties can be studied from ultimate compressive strength, ultimate shearing strength, compressive elastic modulus, shearing elastic modulus,vertical stiffness,level equivalent stiffness etc. The attenuation model of neoprene rubber bearings created by the least square method can be used to derived the fitting curve and the attenuation function.In order to study the force performance change rules of the neoprene bearing under salt freezing condition. Do the full immersion treatment for 20d,40d,60d,80d,100d on neoprene bearing using 3% salt frozing solution. then compressed axially and sheared horizontally. Its changes of the mechanical properties can be studied from ultimate compressive strength, ultimate shearing strength, compressive elastic modulus, shearing elastic modulus, vertical stiffness, level equivalent stiffness etc. The attenuation model of neoprene rubber bearings created by the least square method can be used to derived the fitting curve and the attenuation function.