Study On Road Performance Of Solidified Muddy Soil By Fluidized Bed Combustion Fly Ashes

In recent years, with the rapid development of Chinese economy and thecontinuous expansion of the various types of infrastructure, lots of muddy soilcontinuous being produced and there being no place to pile up.On the one hand, itcauses environmental pollution, and occupies space of urban and farmland, on the otherhand，it affects continued development of the economy. In the many handled measuresof dealing muddy soil, solidification process is an economic and effective technicalone.China has rich coal mine, the structure of coal consumption is a dominant position.However, the raw coal combustion will produce large amounts of solid waste, such asFluidized Bed Combustion fly ashes(FBCF). Therefore,comprehensive utilization ofsolid waste has become an urgent problem.In this paper, utilizing the special composition and performance of FBCF and usingit as a muddy soil solidified material,as well as combining FBCF solidified muddy soilwith high embankment filler closely, by the indoor standard compaction test, theintensity test, water stability test,verify the feasibility of FBCF solidified muddy soil forembankment filler, and validate the conclusion by numerical simulation based onANSYS, the main contents of this article are as follows:1)First,it summed up the domestic and foreign research status of muddy soilsolidification materials and FBCF,then, by indoor experimental study, indicating thatthe adding of FBCF can substantially increase in soil compaction interval, with theincrease of FBCF in the mixture, the density will reduce, while the optimum moisturecontent will increase; solidified muddy soil have higher strength in the early time,thebest incorporation of FBCF is about20%, the further increase of FBCF, no significantincrease on the shearing stress，unconfined compressive strength, CBR value, resiliencemodulus；water stability test shows that20%FBCF solidified soil pre-absorbent islarger, the strength attenuation is also larger. Wet and dry cycling test shows that loss ofwater and intensity attenuation is very gentle.2) According to physical properties of the selected muddy soil,from the soilmineral composition and electrochemical properties, and also combine with chemicalcomposition and physicochemical properties of FBCF, lime and cement, study thechemical nature of solidifying muddy soil with single FBCF, FBCF and lime mixing system, as well as FBCF and cement mixing system,and explain the intrinsicmechanism of the strength of solidified soil from the microscopic morphology.3) The use of the D-P criterion provided by ANSYS simulated the change ofvertical displacement,horizontal displacement and shear stress of high embankmentunder different heights of filling, the results show that20%FBCF solidified muddysoil and plain soil are power series growth in the vertical displacement, horizontaldisplacement with the increase of filling height,but the displacement of stabilized soilare smaller than plain soil,the increase of XY plane shear stress of plain soil isaccording to logarithmic curve, but FBCF solidified soil is according to linear,theshear stress of plain soil is greater than stabilized soil.