粉煤灰复掺碳纳米管改性黏土力学性能研究

Research on Mechanical Properties of Clay Modified by Fly Ash Mixed with Carbon Nanotubes

利用TSZ全自动三轴仪分别对碳纳米管掺量为0、0.5%、1.0%、1.5%和2.0%的粉煤灰复掺碳纳米管改性饱和黏土进行了围压为100 kPa、200 kPa、300 kPa和400 kPa的不排水不固结三轴剪切试验,研究改性饱和黏土的力学性能。试验结果表明:随着碳纳米管的掺入,改性饱和黏土的抗剪强度先增大后缓慢减小,峰值达到561.3 kPa,总体上试验土体的抗剪强度得到提升;内摩擦角先由11.41°减小至9.05°后迅速增大;黏聚力先增大后略微减小,峰值超过170 kPa,总体上试验土体的黏聚力得到了提升。综上可知粉煤灰复掺碳纳米管后能很好地提升饱和黏土的力学性能。

The TSZ automatic triaxial instrument is used to carry out undrained and unconsolidated triaxial shear tests on the modified saturated clay with carbon nanotube content of 0,0.5%,1.0%,1.5%and 2.0%under the confining pressure 100 kPa,200 kPa,300 kPa and 400 kPa to study the mechanical properties of modified saturated clay.Experimental results show that with the addition of carbon nanotubes,the shear strength of the modified saturated clay increases first and then decreases slowly,and the peak value reaches 561.3 kPa.The overall shear strength of the tested soil is improved.The internal friction angle of the modified saturated clay is first reduced from 11.41°to 9.05°,and then increases rapidly.The cohesion force increases first and then decreases slightly,with the peak value exceeding 170 kPa,and in general the cohesion of the test soil has been improved.In summary,it can be seen that fly ash mixed with carbon nanotubes can well improve the mechanical properties of saturated clay.