干湿循环对水泥改良土疲劳强度影响的试验研究

通过振动三轴试验,研究干湿循环过程对水泥改良粉质粘土和水泥改良粉土疲劳强度的影响。结果表明:在动应力作用下,两种改良土的破坏均为脆性破坏;干湿循环次数对水泥改良土疲劳强度的影响与土类有关,而改良粉质粘土疲劳强度经1次干湿循环后,趋于稳定,而改良粉土疲劳强度经2次干湿循环后才趋于稳定;稳定后的疲劳强度大约下降为静强度的38%左右。水泥改良土的破坏塑性应变随干湿循环次数增加有所增加,但是不超过2%。

Test Study on the Effect of Cyclic Dry-wet Process on the Fatigue Strength of Cement-soil

The effects of cyclic dry-wet process on the fatigue strength of the cement silt clay and the cement silt are researched by cyclic triaxial tests. Research results show that the failure styles of two kinds of cement-soil under dynamic load are brittle failures. The effects of cyclic dry-wet process on the fatigue strength depend on the kind of soils. The change of the fatigue strength of the cement silt clay will tend to stability after one cycle of dry-wet process. The change of the fatigue strength of the cement silt will tend to stability after two cycles of dry-wet process. The fatigue strength will degrade about 38% of the static strength after stabilization. The failure plastic strain of cement soils will be increased with the increase of cycles of dry-wet process. But it is no larger than 2%.