Research On The Application Of SMA In Constructing An-bai Expressway

With the rapid development of the national economy, China's expressway construction has gained unprecedented large-scale development, an annual increase rate of several thousand kilometers. However, in the process of rapid development, some asphalt pavement and did not get a good road performance, gradually emerged in the use of a variety of pavement.in the northern, low temperature cracking occurs in winter and semi-rigid reflective cracking of the main crack.the reason for the lack of existing design, construction quality can not be guaranteed, there are road material performance issuesHorseshoe fat crushed stone mixture of asphalt (SMA) is very popular in recent years, an international road surface material. SMA is a kind of bitumen, fiber stabilizing agent, slag, and a small amount of fine aggregate component of asphalt filled with horse fat continuous gradation of coarse aggregate skeleton consisting of the gap and asphalt. It is sufficient asphalt binder and asphalt stiffness with considerable mastic mortar filled in the formation of coarse aggregate stone - stone embedded in the structure of the gap in the extruded form. Therefore, it has anti-wear, rut resistance, resistance to cracking, skid, waterproof, durable and other excellent road performance. Since the 60s of last century the world has begun to gradually get a wide range of applications. China Capital Airport Expressway in 1993, the first application of SMA, followed by another in many provinces of the country began to try to use the highway engineering SMA.In the northern, Chang-yu Expressway, da-guang section of highway Songliao, chang-ji Highway, North Lake highway construction and road reconstruction grew up, Shen-Da Expressway and other highway reconstruction projects using SMA. The use of these projects SMA, the SMA not only possess a good performance, but also use the SMA for the northern cold regions provides a valuable experience for reference.In this paper, Hunchun to Ulanhot White City Expressway to Highway Engineering Da-based, drawing on the surrounding areas of Jilin Province and the success of previous experience with SMA, according to the local climate characteristics, the actual situation of mineral aggregate was modified asphalt SMA technology study.The main contents are:1,SMA asphalt mixture strength of the structural characteristics and formation mechanism2,SMA mixture of elemental materials testing;3,With test section of highway safety and the SMA White Mixture design, including the target mix, the production mix design and production verification with the ratio (test road paving) This is the focus of this thesis research;4,in accordance with the SMA mix design results and the road to face the requirements of the structure, make the construction process, the SMA actual road paving;5,completed testing on the road, according to test results, the SMA pavement to evaluate the pavement performance.After the study, reached the following conclusions:1,In the course of using the SMA can not be copied blindly. In the specific project, it is necessary to be good at drawing and pay attention to innovation .For example, in this project, the first draw of the surrounding provinces of Jilin and SMA pavement with the design method, that the Marshall volume design, and a blend of the uniform design; Secondly, according to project specific design requirements, there are mixed on the SMA separate material mix design and checking.2,SMA mixture with the ratio of the design is simple to say that is the target mix, production mix and production mix verify the three-stage design, but each stage to do a lot of detailed work, and the design results of the SMA can play to their excellent have important influence on the performance. Target ratio is in the room with the results obtained under standard conditions, often can not be directly used for paving roads, in the production mix and production mix in the validation phase, the Marshall test to be repeated to verify the correctness of the design parameters, which have the standard for the actual production mix.3,SMA Mixture Design and Mixture of Asphalt design differences.4,Due to the special nature of SMA pavement structure, so the construction methods and ordinary asphalt different. In the mixing, transport, paving, rolling must ensure that all aspects of quality, in order to ensure access to excellent road performance of SMA. In the construction process, with particular attention to the temperature of mixture control and rolling process control.