宁明膨胀土研究的新进展

广西宁明是著名的膨胀土分布区,20世纪70年代,宁明膨胀土曾造成该区大批工业民用建筑物的严重破坏,对此不少专家、学者曾进行深入的现场调查、变形监测和系统的试验研究。进入新世纪以来随着高速公路建设的迅猛发展,不少公路穿越膨胀土地区,南(宁)友(谊关)高速公路便是其中之一。由于膨胀土对公路的严重危害性以及高速公路对质量的高要求,结合南友路修建,再研究宁明膨胀土工程地质特性及对公路施工和运营的影响有着重要的理论意义和工程价值。另一方面,随着近20年来粘土矿物定量测试技术的进展和膨胀土基础理论研究的深入,再研究在对宁明膨胀土粘土矿物的组成、膨胀土的工程性质与成因关系、膨胀土的干燥活化效应以及改性膨胀土的效果等方面均获得新的进展。

New development in studies on Ningming expansive soils

Ningming county in Guangxi is famous for wide distribution of expansive soil.In the 1970s,lots of industrial and civil buildings were seriously damaged due to Ningming expansive soils.Therefore a detailed site investigation and deforemation monitoring as well as systematic theoretical researches on the expansive soils were carried out by many experts and scholars at that time.Since the beginning of the new century,the construction speed of expressway increased quickly,many expressways traverse through expansive soil regions,such as Nanning to you yi-guan expressway.Because of the special hazard features of expansive soils and the high quality standards of expressway contruction,the comprehensive study of the geotechnical properties of Ningming expansive soils and their influence on the construction and operation of expressway provided with important theoretical meaning and engineering value.On the other hand,with the progress in quantitative testing technology for the identification of clay mineral and the development in the basic theorefical researches on expansive soils in recent 20 years,this study made great progreses with the understanding of Ningming expansive clay minerals,the relationship between the engineering properties of expansive soils and their cause of formation,the drying and reactive action and the effect of the expansive soil improvement.