Study On The Modification And Application Of Asphalt Mixture By SBS

With the development of our country national economy, road traffic is developing constantly; pavement is required stricter criteria, the traditional asphalt pavement having already been not adapt to nowaday need. As for such a condition, at home and abroad, asphalt material has been carried out thorough research. At present, modified bitumen has improved pitch quality effectively, and therefore it has got the extensively approval and apply, and has got fairly better use effect. Stiff segment being composed of polystyrene and soft segment being composed of polybutadiene in SBS give the modified body the unique nature function, whose adaptability is the strongest ;whose effection is best ;whose application prospect is vast.The paper relying on project practice of the express highway from Taiyuan to Changzhi of Shanxi Province, according to demanding of "Technical Specifications for Construction of Highway Asphait Pavements ", combining with own region climate characteristic and concrete design, and construction request, it has carried out SBS modified studying on shell-90# asphalt, so drawing a conclusion:1. Having studied the quantity of SBS modifier's effect on the temperature sensibility, the high temperature stability, the low temperature resistance to cracking , elasticity and the durability of asphalt ,meanwhile, having studied the quantity of SBS modifier's effect on the water stability, the high temperature stability , the low temperature resistance to cracking of asphalt mixture, having compared SBS modified bitumen's various function. As a result ,when the amount of SBS added is 5% , every function is comparatively even. Combining with the area that Taichang express highway rest on, it has hot summer and cold winter and heavy traffic,in 'addition to the request on practical construction technical and economy, the amount of SBS in modified asphalt should be 5% .2. Making use of Marshall to ascertaine the grading of mixture and the optimum pitch dosage, to the bitumen asphalt, the optimum proportion of oil to stone is 4.6%; to. the modified bitumen mix the optimum proportion of oil to stone is 5.0%. Having studied the bitumen asphalt mix and 5% SBS modified bitumen mix 's road-used property on the basis. Results is indicated: by SBS modification , the modified asphalt's rut moving degree of stability increases 3.6 times, compared with that of bitumen asphalt. The asphalt's high temperature function has been improved noticeably; the maximum stress born by modified asphalt mixture has been advanced; the limited strain and deformable ability have been risen, as indicates the asphalt's low temperature resistance to cracking has got rising , and the SBS modified asphalt mix's water stability has also risen to diverse extent, compared with that of bitumen asphalt mix. Therefore, SBS modified bitumen mixture is suitable to the area.3. On the basis of experiments, tried pavement of Taichang express-way is constructed when the content of SBS is 5%. The pavement technology is confirmed and the performance of pavement is tested. It is found that the property of SBS modified asphalt can satisfy the design. Only for 2 years are the road situation fine , and happened there no early disease.