云桂铁路膨胀岩强度特性试验研究

Experimental Study on Strength Characteristics of Expansive Rock along Kunming-Nanning Railway

膨胀岩具有遇水膨胀、软化、崩解和失水收缩、开裂等特性,一直是工程应用中的难点。通过云桂铁路膨胀岩的室内试验研究,分析了膨胀岩的抗剪强度、抗压强度和膨胀力的特性;根据抗剪试验,分析了膨胀岩的抗剪特性,着重研究了水对膨胀岩抗剪强度的影响;同时提出了临界初始含水率的概念[1]。根据膨胀力的试验,分析了膨胀力与膨胀应力的关系,进一步建立膨胀岩的修正Huder-Amberg本构变形模型。成果为云桂铁路膨胀岩的处理问题提供设计施工依据。

Expansive rock will be expanded, softened, and disintegrated when in water and contracted and cracked when loss of water, which is always the difficulty in engineering application. Through the indoor experimental study for the expansive rock along Kunming-Nanning Railway, its characteristics of shearing strength, compressive strength and expansion force are analyzed. According to shearing test, the shearing resistance property is analyzed, especially the effect of water on shearing strength of expansive rock; and the concept of critical initial water content is proposed as well. According to expansion force test, the relation between expansion force and expansion stress is analyzed and the revised Huder-Amberg constitutive model for deformation of the rock is established further. By experimental study, the design and construction basis is offered for treatment of expansive rock along Kunming-Nanning Railway.