Test Research On The Mechanics Characteristics Of Rock-soil Aggregate Mixture

Preestimate the intensity of rock-soil aggregate mixture quickly and accuracy is not only propitious to design and calculate, but also to establish the construction scheme and choose properly compacting method, while the mixture are broadly used in roadbed, dykes and dams, and foundation engineering. But the category existed are always set about from the grain composition, and can not predict its strength. The article supported by West-construct science and technology Item of ministry of communications: study on the construct technology of rock-soil roadbed, based on shear-test on site, lab large-scale shear test, compaction test and numerical simulation by PFC3D, assort the mixture into different levels and kinds according to the intensity of rock and soil, the ratio of rock to soil and the fraction eigenvalue of granule, put forward the diversity on intensity of different kinds mixture meanwhile. This assort method is convenient to apply in practice for the criterion of this method and representative strength of mixture are easy to get.Contrast with shear-test on site, lab triaxial test and numerical simulation, we adopt lab large-scale shear test to research the mechanics character of different kinds mixtures, though it is slightly departure from its test principle——Mohr-Coulomb law. To correct this problem of shear test, we improved the equipment of lab large-scale shear test and developed an especially new one which overcome the disadvantages of normal equipment, make the result more accuracy and can do more analyze about the shear surface, dilatability of the mixture only through shear test.We get the vary rules of mechanics character, study the dilatability and fractal characters of shear surface, analyzed the distortion manner of different kinds mixture, we build the forecast model though test results, while the results are generally same by different test ,so we can use the model to preestimate the mechanics index of mixture quickly.The originalities of the study consist: put forward integrate assort method of mixture according to lithology, rock-soil ratio and fractal character of granule composition, improve the equipments of shear test which can keep vertical stress invariableness and avoid eccentricity, get the vary rules of mechanics character through systematic and vast scale test, study the gurgitation character of the shear test surfers first and build the relationship between intensity index and fractal characteristic number through nonlinear fractal theory.