岩石溶蚀的表现特征及其对物理力学性质的影响

本文以微晶白云石大理岩和黏土质长石砂岩为研究对象,以现场实测及室内试验资料为基础,对岩石溶蚀的表现特征及其对表层物理力学性质的影响进行了研究。研究表明:1)在岩石发生溶蚀的区域,由表及里易溶性矿物成分和易迁移元素氧化物的含量逐渐增加、黏土矿物含量和烧失率逐渐减少,岩样的微观结构也发生了变化,主要表现为岩石表层溶孔、溶隙发育,易溶矿物颗粒表面出现溶孔、溶坑、颗粒间出现溶蚀裂隙等;2)溶蚀使岩石表层强度降低、吸水率增大,溶蚀愈严重表层强度越低、均匀性愈差,吸水率愈大;溶蚀还使岩石的孔隙度及孔隙尺寸明显增大。

Study on the Expressive Characteristics of Rock Corrosion and Its Effect on Physical and Mechanical Properties of Rock Surface Layer

In this paper,based respectively on the data of laboratory and on-the-spot test of two kinds of rock materials,clay feldspathic sandstone and microlite dolomitic marble,the expressive characteristics of rock corrosion and its impact on the physical and mechanical property of rock surface layer are analysed.The researches indicate that: 1)for the corroded part of rock,the content of soluble mineral ingredients and transportable element oxid increases gradually from the exterior inward,while the content of clay mineral and loss on ignition gradually decreases.In addition,the rock samples have completely changed in micro texture,which is mainly expressed by well-developed corrosion holes and corrosion fissures among particles,corrosion holes in the surface of soluble mineral particles;2)the corrosion causes a decrease in strength and an increase in the hygroscopic coefficient of rock surface layer.It is shown that the more severe the corrosion is,the bigger the hygroscopic coefficient and the worse the uniformity and strength of rock surface layer become.What’s more,corrosion makes the porosity and pore size of rock surface layer abviously increase.