【作者】 任新红；

【导师】 谢强；

【作者基本信息】 西南交通大学 ， 地质工程， 2013， 博士

【摘要】 新建南广铁路沿线岩溶发育强烈,地表岩溶塌陷特征明显,覆盖型岩溶成为新建南广铁路路基稳定性的潜在危害。论文以南广线工程建设为背景,结合室内外大规模试验及理论分析,针对铁路岩溶路基注浆效果检测标准及方法开展深入及系统研究。研究过程综合采用资料分析、室内试验、数值分析、现场监测等多种手段,完成的主要研究内容包括以下几方面：1)通过对南广铁路岩溶路基段工程地质背景的深入调研分析,确定现场试验区类型,并基于此建立了粘土覆盖层裂隙灰岩、含砂卵石覆盖层裂隙灰岩、粘土覆盖层溶洞灰岩3种典型地质概化模型。通过对岩溶路基注浆加固目的及检测深度的研究,确定以电阻率法、瞬态面波法、电磁波CT及压水试验法为主要研究的检测方法。2)通过室内模型试验,进行电阻率法注浆效果检测正演研究,研究了注浆前后不同岩溶路基地质概化模型的电阻率法检测效果及地下水位变化对其所产生的影响。研究了装置参数与测试深度的关系、地表覆盖层的影响、地下水位的影响,及不同岩溶路基地质概化模型的电阻率法检测效果与标准。3)通过南广铁路试验段电阻率法注浆效果检测的现场试验,对典型地质断面注浆前后电测深曲线、视电阻率等值线、注浆后不同时间检测效果及电阻率法检测标准进行了深入研究。4)通过室内试验,对现场典型地质介质对象的常规波速特征进行了测试。基于测试结果,结合有限元数值模拟,对不同地质概化模型的瞬态面波法注浆效果检测进行了正演分析。5)通过现场试验,对不同试验区典型地质断面注浆前后的瑞雷面波传播特征、地表质点振动特征及频散曲线变化特征进行深入研究,并结合注浆效果的现场验证,对瞬态面波法注浆效果检测标准进行了深入分析。6)通过进行不同粗糙度管道模型试验、水平线状单裂隙理想模型试验、水平线状裂隙理想模型试验、水平面状单裂隙理想模型试验及三组正交裂隙理想模型试验,对岩体裂隙分布与组合特征、裂隙长度与粗糙度、裂隙开度等因素对压水试验中岩体透水率的影响进行系统分析,并在此基础上对压水试验检测标准进行了研究。7)通过综合对比各种检测方法的检测效果及检测标准,深入研究了各检测方法的关系、综合运用方式及综合检测标准。更多还原

【Abstract】 Abstract:The problem of covered karst is becoming potential hazards of new Nanguang railway’s roadbed stability owing to the strong development of karst and clear features of its surface subsidence. This thesis is based on Nanguang railway construction project, combined with large-scale indoor and outdoor experiments and theoretical analyses. An in-depth and systematic analysis of testing standards and methods for railway karst roadbed grouting effect is carried out. The course of this study applies data analyses, laboratory experiments, numerical analyses, site monitoring and other methods. And the findings of the study are as follows:1. An in-depth investigation and analysis of engineering geologic background Nanguang railway’s karst roadbed defines the types of on-site testing areas. And three typically geological models are formed, the fractured limestone model with clay overburden, the fractured limestone model with sand and gravel overburden, the karst cave limestone model with clay overburden respectively. A study of the purpose of karst roadbed grouting reinforcement, as well as a research of the testing depth determines the testing methods for the resistivity method, transient surface wave law, electromagnetic wave CT and pressurized water testing method.2. Indoor model tests are employed to investigate the resistivity method grouting effect, and the influence of generalized model’s resistivity testing effect with different karst roadbeds before, after grouting and groundwater level changes on it. Another study is carried out, focusing on the relationship between device parameters and testing depth, cover layer’s impact, underground water levels’impact and different karst roadbed geological generalized model resistivity testing effect and standards.3. An in-depth analysis of the electrical sounding curve before and after grouting, the apparent resistivity contour before and after grouting, different time detection results after grouting, and the resistivity-method testing standards after grouting in the typical geological cross-section of the different pilot areas is presented via the grouting effect testing of Nanguang railway.4. Laboratory experiments are to test the conventional wave velocity characteristics of the scene typical geological media objects. And a detailed analysis of grouting effect testing standards with varying geological generalized models is presented based on the test results, combined with the finite element numerical simulation.5. An overall analysis of grouting effect testing standards with instantaneous surface wave method is employed, based on the field trials of the Rayleigh wave propagation characteristics of typically geological cross-section in different pilot areas before and after grouting, surface particle vibration characteristics and the variation of dispersion curves, united by site validation for grouting effect.6. A systematic analysis of the influence of fracture distribution and combination characteristics, fracture length and roughness, fissure opening degree on the rock permeability rate in water pressure testing is adopted, based on the pipe model test with different roughness, horizontal-lined single fractured deal model test, horizontal-surfaced single fractured deal model test,and three sets of orthogonal fissures ideal model test.7. An in-depth study of the relationship of various detection methods, integrated ways and full testing standards is accomplished through the comprehensive comparison of various detection methods and testing standards.更多还原