鄂北地区膨胀土强度特征及其改性研究

以鄂北地区膨胀土为研究对象,对其进行了天然状态击实试验,研究了其物理力学特性,试验发现其工程特性难以满足填筑工程要求,需要改性处理。根据设计的石灰改性膨胀土(4%、5%、6%、8%掺合比)、粉煤灰改性膨胀土(30%、40%、50%、60%掺合比)和4∶40∶56石灰粉煤灰改性膨胀土击实试验及其物理力学试验,研究发现改性效果明显,各方案均能满足填筑工程要求;其中6%掺合比石灰改性膨胀土、40%掺合比粉煤灰改性膨胀土和4∶40∶56石灰粉煤灰改性膨胀土方案相对较优。最后提供了较优方案的击实试验和强度参数供类似工程设计参考。

Modified Treatment and Strength Features of Expansive Soil in North of Hubei Province

Expansive soil in north of Hubei province is studied.Then,compaction test of the raw soil is done,whose physical and mechanics features are studied.It is found from these experiments that the engineering features of the raw soil are not fit for reclamation requirement.And the soil disposed can be used.According to the compaction and other tests designed such as modified treatment by lime with 4%,5%,6%,8% mixture ratio,fly-ash with 30%,40%,50%,60% mixture ratio and lime and fly-ash with 4∶40∶56 mixture ratio,their physical and mechanics characteristics are studied,Found that the modified effect is apparent and all schemes can meet the project requirement,And 6% lime,40% fly-ash and 4∶40 lime-flyash schemes are better than others.Finally,the compaction test and strength parameters of these optimal modified treatments are presented to supply design reference to similar projects.