Experimental study on the mechanical properties of lead rubber bearings in acid rain environment

Abstract

In order to study the law of the mechanical properties of lead rubber bearing (LRB) after being corroded by acid rain, the artificial acid rain corrosion solution with pH of 4.5 and 3.0 was used to conduct corrosion tests on 9 LRBs with a diameter of 300▒mm for a total duration of 92 days. During the test period, the basic properties of LRB were tested regularly, and the test results before and after the experiment were compared. Through the analysis of the results, the law of the mechanical properties of the LRB with the increase of acid rain corrosion time was obtained. The test results show that, the effect of acid rain corrosion on the vertical compression stiffness of LRB is about 10%. The effect of acid rain corrosion on the compressive performance of LRB is not obvious. The yield force (Q d), and horizontal equivalent stiffness (K h), the equivalent damping ratio (h eq) of the LRB, will decrease at first and then increase with acid rain corrosion time. When the shear strain is 100%, the maximum decrease of Q d are 15.483%, 21.827%, and 14.388%, respectively. When the acid rain is strong, the degradation of K h is more obvious. The Q d, K h,h eq of the unprotected support decreases faster, indicating that the shear performance of LRB is more sensitive to the corrosive effect of acid rain. Actually, we found the degree of shear performance degradation is strongly influenced by the acidity, the presence of the protective layer.