Research On Cracking Prevention Of Two-ash Crushed Stones Base Course

Because of high bearing capacity, availability of materials conveniently and simple construction, semi-rigid base course is applied extensively. Two-ash crushed Stones is a kind of semi-rigid base course, which is a mixture made of lime and fly ash in a certain proportion, and joined with a certain amount of crushed stones. Making a reasonable use of the industry discards and residues, lowering cost of construction projects and reducing pollution to the environment, so two-ash crushed stones are a common material of highway construction. However, this material is so easy to cracking that the life of pavement is lower. So how to prevent two-ash crushed stones from cracking is a key problem. Exploring and studying for many years, cracking of two-ash crushed stones base course is prevented by adjusting synthetically grading, construction process and asphalt sealing. Test roads of two types of two-ash crushed stones base course were paved from Dongyin to Qingzhou in Shandong province. By comparing the test road performance, a kind of the two two-ash crushed stones base course is choose as recommended value, which is the type of dense grading, less drying and thermal shrinkage coefficients and high strength. Meanwhile, to be better to prevent cracking of two-ash crushed stones base course, construction process is adjusted correspondingly. The test road has been in service for about 7 years. The cracking is well prevented. So the grading and construction process of two-ash crushed stones base course are suitable to recommend. The technology is not only solving the cracking of two-ash crushed stones base course, but also segregation, evenness and strength of two-ash crushed stones base course. The research results are of guiding significance to application of two-ash crushed stones base course in Shandong province.