【作者】 曾健新；

【导师】 文江泉； 吴俊猛；

【作者基本信息】 西南交通大学 ， 地质工程， 2012， 硕士

【摘要】 红层是红色陆相沉积为主的碎屑沉积岩层,岩性以砂岩、泥岩、粉砂岩和页岩等为主。红层软岩具有透水性弱、亲水性强,遇水易软化,失水易崩解,强度低、易风化等特性,其工程地质问题非常突出。达成线扩能改造工程地处川东红层地区,由于红层地区软岩所具有的特殊工程特性,较大的影响和制约着铁路的修建和运营。因此本文基于对该线区域地质调绘、勘探、原位测试及室内外试验、实验,采用数理分析与工程实例相结合,对川东红层地区工程地质问题进行了系统的研究。本文通过对沿线岩土的物质成份、岩土物理力学参数的统计,以及对代表性段落取样进行崩解、蠕变实验所获得的实验数据进行数理分析；系统的阐述了红层工程地质性质与其物质组成、结构特征等因素有关,揭示了红层的物质结构特征是决定其物理力学性质的内因,对红层工程地质性质起主要的控制作用。同时本文还通过对沿线水化学特性的统计分析,阐述了水对红层的物化效应及对混凝土的侵蚀性影响。结合达成线扩能改造工程存在的主要工程地质问题,例举工程实例,系统的阐述川东红层工程地质特性在铁路建设中对路基、桥梁、隧道的影响,以及红层作为路基填料路用局限,并给出了相应的治理对策和建议。更多还原

【Abstract】 Red layers are predominantly fragmental sedimentary rocks of red continental deposit, which typically consist of sandstone, muddy siltstone, siltstone, and shale, etc. Red layers are low in permeability, high in hydrophilicity, low in strength, easily soften in water and disintegrated if dehydrated, so the slopes of red layers are easy to slide, which causes lots of geologic hazards during construction. Expansion and reconstruction railway project from Dazhou to Chengdu is located in the eastern part of Sichuan where red layers are well developed. Due to special engineering characteristic, it results in greater influences on construction and operation of the railway. Based on regional geology investigation, exploration, in-situ testing and laboratory and field experiments along the line, detailed studies have been carried out on engineering geology characteristics of red layers in the eastern part of Sichuan with the combination of mathematical analysis and engineering example in this paper.Compositions, constitutional features and physical mechanic properties of red reds and relations between them were systematically studied with statistics and analysis of material composition, rock and soil physical and mechanical parameters as well as results from representative sample disintegration and creep experiments, which reveals that the physical structures of red beds are the inner to determine physical mechanic properties, and play a key role in the engineering geological properties. At the same time, the physical and chemical effects of water on the red layer and the erosion of water on the concrete were also studied with statistics and analysis of water chemical characteristics along the line.At last according to the main engineering geological problems of red layers along the line, the effects of red layers on roadbed and bridge, tunnel, and the limitations as subgrade filling with engineering examples, and the corresponding countermeasures and suggestions were given.更多还原