纤维石灰土工程性质的试验研究

Experimental study on engineering properties of fibre-lime treated soils

为了解决石灰改良引发的填筑土脆性破坏的问题,本文提出了将分散的聚丙烯纤维丝掺入到石灰土中的设想,并对不同纤维和石灰掺量的6组土样分别进行了无侧限抗压试验、剪切试验、膨胀率试验和收缩试验。试验结果表明,纤维的掺入不仅提高了石灰土的强度,而且还增强了石灰土的塑性,使其破坏形式从脆性破坏转变为塑性破坏。此外,在胀缩性方面,纤维的掺入减小了石灰土的膨胀性,但增加了收缩性。研究表明,纤维的强抗拉性是导致石灰土工程性质改变的主要因素。因此,纤维和石灰的混合掺入可以为填筑土工程性质的改良提供一个更加有效的方法。

For the purpose of preventing lime-treated filled soils from brittle failure, an attempt to admix discrete polypropylene fibre into lime soil was put forward. Six groups of soil samples were prepared at different percentages of fibre and lime content and were subjected to four tests including unconfined compression test, shear test, swelling percentage test and shrinkage test. It was indicated by the test results that the presence of fibre gave great rises to the strength and plasticity of lime soils, which changed the failure mode of lime soils from brittleness to ductility. Furthermore, addition of fibre caused a decrease in swelling potential of lime treated soils while led to an increase in shrinkage potential. It was shown that the improvement of engineering properties of lime soils was mainly attributed to the development of tension in fibre. It therefore was concluded that the addition of fibre and lime mixture could be considered as an efficient improvement method for engineering properties of filled soils.