| Road traffic noise pollution and scrap tire environmental pollution are potential health and ecological threats that have become more prominent with the acceleration of urbanization and population growth.Some researchers have begun to focus on porous elastic road surfaces because they can achieve excellent noise reduction function while consuming a large amount of waste tires.However,there is currently no mature method for designing porous elastic road surface mixtures,and their technical performance is complex,leading to shorter service life of test roads paved with these mixtures.Therefore,studying the design and technical performance of porous elastic mixtures is beneficial for gradually improving the durability enhancement technology of porous elastic road surfaces and promoting their role in building livable cities and reducing solid waste material pollution.This paper is based on the design principle of volume method,with mineral aggregate and rubber particles as the skeleton.Polyurethane and mineral powder are filled into the structure with the target of porosity rate.Considering the large rebound deformation ability of rubber particles,suitable mixture compaction methods are analyzed.The mechanical and road performance tests of the mixture were conducted to analyze and select the best ratio of mixture.The impact of rubber content on the noise characteristics of the mixture was studied in combination with noise reduction performance.The mixture used is called Polyurethane Porous Elastic Road Surface mixture,and the compaction method used is superpave gyratory compaction.Firstly,according to the structural characteristics of the mixture,raw materials such as feldspar,rubber particles,and limestone mineral powder were selected,and their key technical properties were experimentally analyzed.Suitable road use polyurethane was selected through mechanical performance and curing characteristics analysis.Secondly,based on the research experience of Polyurethane Porous Elastic Road(PERS)in Europe,two particle size ranges(2.36～4.75 mm,4.75～7.5mm)and three rubber particle contents(5%,10%,20%)of raw materials were determined.In order to explore the influence of instrument parameters on aggregate grading attenuation during the Marshall compaction and superpave gyratory compaction(SGC)molding processes,a large number of experiments were conducted to reveal the influence of rubber particle content and molding parameters on aggregate grading attenuation,quantify the impact of each factor on the volume indicators of the mixture,and determine the suitable molding method and parameters for Polyurethane Porous Elastic mixture.Specifically,the method is to use the SGC method with a rotation of 90 times,a pressure value of 200 k Pa,and a rotation angle of1.25°.To ensure the target porosity rate,a polyurethane skeleton void structure mixture was designed using the CAVF(Coarse Aggregate Void Filling)method,which is based on the extrusion of the main aggregate.The target mix ratio was designed based on the target void ratio.The effect of different rubber contents on the mechanical properties and deformation capacity of the mixture was studied by changing the proportion of the four components in the mixture.To ensure the road performance and noise reduction performance of the mixture,hightemperature performance,low-temperature performance,and water stability tests were carried out on mixtures with different rubber contents.The influence of aggregate particle size and rubber content on the anti-skid performance and texture of the road surface was investigated by analyzing the road surface texture using a laser texture scanner.Based on the noise reduction mechanism of porous elastic road surfaces,the sound absorption performance of the mixture was evaluated using an impedance tube,and the elastic performance of the mixture was evaluated using the rebound modulus.Finally,the noise reduction model was used to predict the overall noise reduction capability of the mixture. |
PDF Full Text Request