Study On Typical Structure Of Asphalt Pavement And Road-building Materials In Tibet

In recent years,China's investment in highway construction in Tibet has continued to increase.However,due to the special climate and environment in Tibet,the research on the materials and structures of road materials for asphalt pavement is not comprehensive enough,which has resulted in the cracking of road surfaces in the Tibet region.,so pavement structure and road building materials were studied to find pavement paving materials and structures suitable for use in Tibet to provide assistance for the construction of highways in Tibet in the future.In this paper,we can see from the results of the road survey that road surface cracking in Tibet is one of the major road surface diseases in this area.Therefore,this paper addresses the problem of road surface cracking in Tibet from two aspects.On the one hand,by looking for materials with high crack resistance and simultaneously taking into account the high temperature stability and water stability of the mixture,on the other hand,the road surface structure suitable for the region is selected for each region in Tibet.Pavement paving materials This article through comparison and selection,the final choice of compound rubber powder dry mix modified asphalt mixture for indoor testing,by changing the amount of rubber powder on the mix of road performance.In terms of crack resistance,low temperature bending test and fatigue test were used to verify the low temperature crack resistance and fatigue cracking resistance of the mixed materials respectively.Rutting test and freezing and thawing cracking test were used to verify the high temperature performance and water stability of the mixture,according to the test results.The applicability of mixture properties in Tibet is judged.For the selection of the pavement structure,this paper first collects and investigates climatic data in Tibet,and according to the collected climatic data,uses SPSS classification for climate zoning and divides Tibet into several different climatic zones.According to the results of the partition,different parameters of the pavement structure layer are selected,and the selected combinations of different pavement structures are numerically simulated.The material parameters of each zone are selected according to the climate of the region.Finally,the road surface structure in each region of Tibet is recommended through numerical simulation calculation.According to the results of the laboratory test in this paper,it can be seen that the modification of the asphalt mixture with the compound powder is beneficial to improve the road performance of the asphalt mixture,the crack resistance performance and the high temperature stability performance are obviously improved,and the water stability is also slightly improved.The election,this article thinks that 22% rubber powder content of modified asphalt mixture is more suitable for Tibet.Based on the numerical simulation results,this paper presents the corresponding pavement structure recommendations for the secondary and sub-secondary highways in various regions of Tibet,and verifies the conclusions of this paper based on the paving results of the test roads.