【摘要】 低黏性粉质黄土的架空弱胶结微结构,导致这种黄土在动荷载作用下呈现出强度低、震陷变形大的现象,为黄土场地地基处理提出了挑战性的技术难题。黄土结构改性是通过改变其微观结构,达到有效降低震陷变形和湿陷性等为目的。本文采用酸改性方法处理黄土,即通过加入有较强分散和胶结效果的硼化合物作为主要改性物质;加入轻质碳酸钙等填料,调整原状土的颗粒粒径级配;以磷酸稀释液调解土的pH值。对改性土样进行震陷等试验测试对比,确定最佳配方,同时分析改性前后微观结构和能谱的变化。结果表明,酸改性方法能有效改善黄土的微观结构,使得土样的震陷变形系数明显降低。并且所添加的改性原料无毒,不会对土层产生污染。更多还原

【Abstract】 The loess with low viscosity and large number of powder particles,has weak-cemented and more frame-holes microstructure,which could lower its dynamic strength and induce large seismic subsidence deformation under dynamic loading.It brings some challenges technology problems for foundation treatment in engineering construction.The acidified modification method is through by changing the loess microstructure from base to reduce its dynamic deformation and collapsibility.The modification method is by adding below,the boron chemical compound,the main materials can produce strong dispersed and cemented effect,light calcium carbonate,to adjust the original loess particles size gradation,and the diluted phosphoric acid,to adjust the original loess pH value.Moreover,through contrasting the seismic subsidence test and others by different ingredients,then analyzing its microstructure and energy spectrum before and after modification,the best proportion of ingredient is determined.The study results show that the acid-modified method can change the loess microstructure and reduce the seismic subsidence conefficients effectively.In addition,the all modified adding materials have non-toxic,and have no pollution to the soil.更多还原