| Semi-rigid base has been widely used in China’s highway construction, of which more than90%are semi-rigid base asphalt pavement structure, to become China’s major highway structure. Semi-rigid base is superior, but there are some defects, for example, poor tensile strength, easy to crack, so the flexural tensile performance of the semi-rigid base is very important.In this paper, the splitting strength test and flexural tensile strength test are used to predict the flexural tensile performance of cement stabilized macadam. The influence of cement dosage, curing age and specimen size on splitting strength are analyzed by splitting strength test, which show that the splitting strength increase with the growth of cement dosage and curing age and that splitting strength size effect exists by the contrast of the strength of cylinder specimen and cube specimen. The non-standard beam specimens40x40x200mm, which are cut from beam specimens100x100x400mm, are used in the flexural tensile test. The loading mode in the test is center loading mode. The test analyzes the variation of flexural tensile strength with cement dosage, curing age as well as curing temperature. The test results show that flexural tensile strength of cement stabilized macadam present growth trend with the increase of cement dosage and curing age and that lower temperature isn’t benefit to the formation of flexural tensile strength. And the laws are consistent with the laws of standard flexural tensile strength. In addition, the correlation of splitting strength and flexural tensile strength are studied, which discover that splitting strength is lower than the flexural tensile strength and that the ratio don’t have significant change with the variation of cement dosage and curing age. The results illustrate that the growth rate of the strength with age is basically the same, and by the impact of cement dosage. Last, calculated by the finite element model, splitting strength, flexural strength and compressive strength was further analyzed.By the experimental study, a better understanding of the flexural tensile performance of cement stabilized macadam is acquired and a new test method of flexural tensile strength is put forward, which can provide a reference for laboratory test. |
