采用室内三轴试验,研究了生物酶、石灰、水泥改良膨胀土的应力-应变曲线及强度特性,探讨了生物酶、石灰、水泥含量对改良膨胀土强度影响的变化规律.试验结果表明:1)改良膨胀土的偏应力随轴向应变的增加而增加,掺生物酶改性膨胀土的试验曲线表现为硬化型,掺石灰、水泥改性膨胀土试验曲线表现为软化型;2)掺生物酶、石灰、水泥能提高膨胀土体承受偏应力的强度,相同围压下,掺1∶300(酶与水的质量比)生物酶试样承受的偏应力最大,掺7%的石灰次之,最后为掺9%的水泥;3)通过比较分析强度提高系数R可知,掺1∶300(酶与水的质量比)生物酶对提高膨胀土抗剪强度效果最佳.以上研究结果为娄益高速处置膨胀土路基提供量化资料,同时也为其他膨胀土工程提供参考.%Laboratory triaxial tests were carried out in order to understand the stress-strain relationship and strength property of bio-enzyme-treated, lime-treated and cement-treated expansive soil.The effect change of biological enzyme, lime and cement content on the strength of expansive soil was studied.The laboratory test results show as follows: 1) With the increase in axial strain, the deviator stress increases, and the bio-enzyme-treated expansive soil relation curves of deviator stress and axial strain present as hardening type.The lime-treated and cement-treated expansive soil relation curves show softening type.2) The deviator stress of bio-enzyme-treated expansive soil, lime-treated expansive soil and cement-treated expansive soil is increased.Under the same confining pressure, the destructed deviator stress of 1∶300 bio-enzyme-treated sample is the biggest, the 7% lime-treated sample is middle and 9% cement-treated sample is the least.3) By analysis and comparison, the strength of mid-expansive soil after 1∶300 (enzyme to water mass ratio) bio-enzyme-treated is largely increased and 1∶300 (enzyme to water mass ratio) bio-enzyme is optimum added quantity.All results can provide the quantitative information for Louyi expansive soil, at the same time, it can also be used as p the necessary reference for other expansive soil area.
展开▼
