冻-融循环作用下云南红土的高压压缩试验研究

Study on High-pressure Compression Tests of Yunnan Laterite under Freeze-Thaw Cycles

以云南红土为研究对象,以冻-融循环作为控制条件,考虑冻-融循环次数和不同固结压力2个影响因素,进行最大固结压力为3.2 MPa的单向固结压缩试验,研究冻-融循环作用下云南红土的高压压缩特性。结果表明,冻-融循环作用对红土压缩特性的影响在一定程度上受固结压力的控制,当固结压力较小时,冻-融循环作用对红土压缩特性的影响明显,高压条件下这种影响会变小;冻-融循环作用对红土压缩特性的影响在第1次时最为明显,反复冻-融循环作用下这种影响会减小。

Taking Yunnan laterite as the research object and the freeze-thaw cycle as the control condition,the compression test with a maximum consolidation pressure of 3.2 MPa is carried out to investigate the high-pressure compressibility of Yunnan laterite under freeze-thaw cycles,in which,two influencing factors of the number of freeze-thaw cycles and different consolidation pressures are taken into account.The results show that,(a)the effect of freeze-thaw cycling on the compressibility of Yunnan laterite is to some extent controlled by the pressure,and the effect of freeze-thaw cycling on the compressibility of laterite is obvious when the pressure is smaller,but the effect will become smaller under high-pressure condition;and(b)the effect of freeze-thaw cycling on the compressibility of laterite is most pronounced in the first instance and is reduced by repeated freeze-thaw cycling.