NIU Heng,SUN De'an,RUAN Kunlin.Mechanical Properties of Shanghai Soft Clay Mixed with Fly⁃ash and Lime Fly⁃ash[J].Journal of Disaster Prevention and Mitigation Engineering,2020,40(06):992-1000.
NIU Heng,SUN De'an,RUAN Kunlin.Mechanical Properties of Shanghai Soft Clay Mixed with Fly⁃ash and Lime Fly⁃ash[J].Journal of Disaster Prevention and Mitigation Engineering,2020,40(06):992-1000. DOI: 10.13409/j.cnki.jdpme.2020.06.019.
Mechanical Properties of Shanghai Soft Clay Mixed with Fly⁃ash and Lime Fly⁃ash
Fly-ash and lime fly-ash are commonly used for improving soft soil behavior. To investigate the improvement effects of the content and curing time of fly-ash and lime fly-ash on the mechanical behavior of Shanghai soft clay, secondary consolidation tests and direct shear tests were conducted. It was found that the coefficient of secondary consolidation of disturbed soft clay decreases obviously with increasing fly-ash or lime fly-ash content. Under the same condition, the content of lime fly-ash has a greater influence on the secondary consolidation coefficient. The mixture of fly-ash or lime fly-ash in Shanghai clay can improve the shear strength of the soft clay. With the prolonging of the curing time, the shear strength of the soft clay with different contents of fly-ash or lime fly-ash increases first sharply and then smoothly, and finally it tends to be stable at a certain curing time. The shear strength of Shanghai soft soil mixed with fly ash increases linearly with the content and the best curing age is 56 days. Adding 10% of lime and fly-ash can effectively improve the shear strength, and the best curing age is 28 days. These conclusions can provide a useful reference for soft soil improvement.
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