Study About Road Performance And Bearing Capacity Mechanism Of Fly Ash

The emission amount of fly ash caused by thermal power plant annually and theaccumulated stockpiles ascended, with the sharp increase of energy consumption. As aresult of the fact, a series of environmental problems have attracted the attention ofthe whole society, the comprehensive utilization of fly ash becomes a matter of greaturgency. For the past few years, a good deal of fly ash were utilized in the rapiddevelopment of China’s highway construction, the available of fly ash accumulationsite treatment soared either. The bearing capacity of Fly ash sub-grade and buildingfoundations are affected by their shear strength. Moreover, water content and thedegree of compaction have a close relationship with the shear strength of fly ash.Meanwhile, the research of bearing capacity mechanism of fly ash around the worldlags far behind their engineering practice. Therefore, it is necessary to carry researchon the road performance and bearing capacity mechanism of fly ash, in order to bemore rational and effective in guiding the engineering practice.The road performance and bearing capacity mechanism of fly ash has beenstudied systematically in the thesis, by taking laboratory tests combined with relevanttheoretical calculations and analysis. A comprehensive review of the chemicalcomposition and microstructure of fly ash is proposed in the dissertation, at the sametime, a wide range of tests is conducted in explaining their basic physical propertiesand mechanical properties. The strength theory of fly ash soil is presented based onthis, which including Mohr-Coulomb failure criterion, the strength formationmechanism and their influencing factors. By performing triaxial compression tests,the influence of water content and degree of compaction on the strength of fly ash isdiscussed, and stress-strain characteristic of fly ash is analyzed. The results of testsindicate that along with the increase of water content under the test range, thecohesion of fly ash increase first and then decrease, however, angle of internal frictionreduced all the time.The shear strength formula of fly ash based on the water content is proposed inthe research by linear regression of the test results. The deviation of the formula iscontrolled under the allowable range of real project, and the calculation parametersare easily available. By conducting related models, the upper limit analysis methodand the Swedish slice method are adopted respectively in terms of calculating the bearing capacity of the fly ash foundation and analyzing the slope stability. What’smore, the compaction of water content on the bearing capacity of fly ash foundationand slope stability is investigated in the dissertation.