Study On Development And Performance Of Freeze-thaw Permeability Concrete

With the acceleration of the urbanization process,the cement concrete pavement is laid in a large area,and the area of the permeable ground is gradually reduced.This has brought many unfavorable ecological environment.In the face of the increasingly serious water shortage and environmental problems,the application of ecological concrete is more Ecological civilization construction requirements,to improve the urban ecological environment,to achieve the recycling of water is of great significance.In this paper,based on the research of antifreeze permeable concrete,the existing strength of pervious concrete and the lack of antifreeze performance were studied on the basis of the previous research,the mechanical properties,frost resistance,water permeability and impact resistance of pervious concrete were studied by adding synthetic fibers and additives.By using the method of physical experiment and numerical simulation,discusses the effect of various addition materials on the performance of pervious concrete from the perspective of macro and micro properties of concrete failure mechanism,and provides a theoretical basis for the popularization and application of pervious concrete in a wider range,which provides a theoretical basis for the wider application of permeable concrete in a wider range of applications.First of all,by reference to the overall understanding of pervious concrete,understanding at home and abroad on the pervious concrete research methods,to determine the approximate range of the mixed material,and according to the research direction of evaluation indexes are selected to measure the performance of pervious concrete.Secondly,select the target of water cement ratio,porosity,plastic fiber and polyacrylonitrile fiber four control factors,and then we were studied with single factor water cement ratio,through the analysis of test results,the rate of water cement ratio range were determined in order to ensure the good strength and permeability,after that,based on the water cement ratio were investigated by single doped test steel fiber and polyacrylonitrile fiber,through the analysis of test results,to determine the approximate range of steel fiber and polyacrylonitrile fiber content.Then,on the basis of the results of the above single factor experiment,the orthogonal test of the mix proportion of pervious concrete is carried out to determine the proportion of the pervious concrete and optimize it.Based on the analysis of the results of orthogonal test,the effects of four factors on the compressive strength,permeability coefficient,permeability coefficient and frost resistance of pervious concrete are determined,Based on the analysis of test results,the proportion of pervious concrete is obtained,on the basis of the basis of the ratio of the optimization of the basic mix and measured the performance indicators after optimization and the optimization of the mix proportion is carried out.Finally,on the basis of the pervious concrete production of optimal proportion of impact test specimens,measured the anti shock performance of pervious concrete under different working conditions,analyzed the influence of materials on the anti shock performance of pervious concrete,the failure mechanism of pervious concrete.To provide a theoretical basis for the engineering application of pervious concrete.Through the experimental study,we get the following conclusions: The relationship between the water-cement ratio and the strength of the permeable concrete is different from that of the ordinary pervious concrete.After determining the relationship between the water-cement ratio,the strength,the porosity and the permeability coefficient,the optimum water-cement ratio is determined.The results show that the strength of pervious concrete is improved after the addition of fiber,which can improve the mechanical,antifreeze and impact resistance of pervious concrete effectively increased about 30%,the frost resistance increased by 55%,and the impact resistance was improved by 60%.The test method of fiber,rubber powder and sand composite enhanced the anti-freezing performance of pervious concrete,which created the conditions for the promotion of the northern cold areas.