Research On Crack Resistance Property Of Road Cement Concrete Under Freeze-Thaw Cycling

Concrete pavement freeze-proof durability has become a hot spot in the study of civilengineering at home and abroad. Two-thirds of the country’s territory area is seasonalfreezing in our country, where a large proportion of the highway roads are different degreesuffered ordinary freeze-thaw damage and salt frozen damage. But so far, the cementconcrete pavement freeze-thaw damage is not effectively resolved and the model is not reallyunderstand, it is not enough in researching how to prevent frozen damage, it is necessary tofurther explore the influence factors of freeze-proof durability of concrete road and thechanging regularity of pavement performance after suffered the freeze-thaw damage in orderto provide the reference for pavement design, maintenance for later.This article in view of the problems of concrete pavement become destroied afterlong-term undergo the freeze-thaw cycle in cold area. Starts from the freeze-thaw mechanism,through the test, summarizes the influence factors of freeze-thaw destroy and the decay lawof the road performance. Analyzes the influence factors of salt frozen, suggest someimprovement measures and design standard about the deicer-frost resistance of the pavementconcrete, Aims for providing the theory basis of pavement concrete durability design andassessment in cold area.This paper analyzed how the different water cement ratio, different air content andstomatal structure influence the frost resistance of concrete through the experiment, damagedegree of concrete is known after200times trial. Test performance after the specimens sufferfrom50to200times repeat freeze-thaw cycle test, compared the quality loss rate, dynamicmodulus of elasticity, flexural tensile strength, compressive strength, crushing ratio, waterabsorption between the initial specimen and freeze-thaw cycles specimens, summarizing thedecay law of the performance that the road in frost environment.Analyzed what factors influence the durability when concrete in the deicing saltenvironment, such as the salt solution types, salt concentration, water cement ratio, aircontent. Put forward some improvement measures to improve the frost resistance. Accordingto the method provided by Specifications of Cement Concrete Pavement Design forHighway,calculate the usage life span of road after freeze-thaw cycling.Calculate the freeze-thaw cycling damage of typical area cement concrete pavement which suffer naturalfreeze-thaw conditions,the results demonstrate that the freeze-thaw cycling damage is seriousto cold cement concrete pavement.