Study On Damage Of Concrete Surface Dry Ice Cleaning

With the rapid development of national economy, and the improvement ofpeople’s living level, the tunnel cleaning has become a topic of concern. The dry icecleaning technique that has researched in this paper is a kind of method with feature ofenvironmental protection, efficient, fast and safe. The dry ice cleaning used in tunnelcleaning can make tunnel safe, comfortable and open, thus can create a beautifulenvironment for people to travel.This paper used the ANSYS numerical simulation to study the effect of dry icemicro-explosion on concrete and its surface pore. Through dry ice cleaning concreteexperiment, this paper study the impact of dry ice cleaning on concrete from cleaningeffect, compressive strength and surface damage and so on. The main research resultsare as follows.State the physical mechanic feature of the concrete briefly. Meanwhile from themechanism and effect size to analyze the influencing factors of the concrete dry icecleaning.Due to the deformation of concrete is little, the dry ice micro-explosion is basicallyno influence on concrete and its surface pore.The test of concrete dry ice cleaning results show that dry ice cleaning caneffectively remove the dirt on the surface of concrete, has little effect on thecompressive strength of concrete, and due to the density and surface regularity ofconcrete is relatively low, the concrete surface appear hole after dry ice cleaning.The range analysis results shows that the most important factor to the surfaceporosity growth is dry ice flow, with the dry ice flow increase, the surface porositygrowth increased, and the surface porosity growth will leap when the dry ice flow isgreater than1.54kg/min; the injection angle has obvious influent on the surface porositygrowth, when injection angle is in the scope of55°~60°and85°~90°,the amount of poreis more than in the scope of65°~70°and75°~80°; the influence on the surface porositygrowth of cleaning distance and cleaning time is not obvious. By linear regressionanalysis and AHP can obtain the weights on the surface porosity growth of four factorsthrough which can get the primary and secondary order of each factor, and the result isconsistent with the range analysis. As a new cleaning technology, dry ice cleaning technology will experience a longprocess from known, trial, testing and use to widely spread. The dry ice cleaningtechnology is used in the tunnel also need more study and practice.