聚丙烯纤维加固软土的试验研究

Experimental study on polypropylene fiber improving soft soils

为了研究聚丙烯纤维加固软土的效果和机制,改善石灰土和水泥土的脆性破坏形式。在试验中将纤维按质量百分比为0.05%,0.15%和0.25%的掺量分别掺入到素土、石灰土和水泥土中,按不同的配比配制了20组试样,进行了无侧限抗压强度试验。试验结果显示:纤维的加入能在小范围内提高素土的无侧限抗压强度,并且强度值随纤维掺量的增加而增加;而在石灰土和水泥土中只要掺入少量的纤维就能使无侧限抗压强度值得到极大的提高,增加了石灰土和水泥土的抗拉强度,改善了它们的脆性破坏形式,并使其水稳性得到改善。

For the purpose of improving the strength and stability of soft soil,studying the effects and mechanical properties of fibre reinforced soil;the polypropylene fibre has been chosen as the reinforcement material of soft soil.Therefore,in the present investigation,fibre was randomly included in to the raw soil,lime soil（with 5 % and 8 % lime content） and cement soil（with 5% and 8% cement content） at three different mass percentages of fibre content,i.e.0.05,0.15 and 0.25 %.Twenty groups of samples were prepared at different percentages of fibre,lime and cement and were subjected to the unconfined compression test;the main objective of this investigation had been focused on the effect and strength mechanism of the soil reinforced with randomly included fibre.The test results have clearly shown that increasing the fibre content resulted in a small increase in the unconfined compressive strength of raw soil;while the inclusion of little fibre dramatically enhanced the unconfined compressive strength of lime soil and cement soil,the brittle characteristic was weakened and the stability in water was improved with the addition of fibre in lime and cement soil.