【作者】 陈廷方；

【导师】 崔鹏；

【作者基本信息】 西南交通大学 ， 岩土工程， 2009， 博士

【摘要】 工程建设对环境的影响越来越受到众多学者的关注。道路工程与地质环境的关系尤为密切。道路工程建设和地质环境的失调可导致地质环境的恶化,产生次生地质灾害。因此,对区域大开发、运输需求急剧增长而地质条件复杂的西部山区,加强对山区道路工程地质环境影响机制的研究,以期减少对地质环境的扰动及由此造成的次生地质灾害,保障工程建设与运营安全迫在眉睫。本文结合国家自然科学基金重点项目“西部地区重大道路工程与环境相互作用机制”,四川省交通厅项目“复杂地质条件区道路工程环境影响评价”及“西-攀高速公路地质灾害研究与对策”等科研项目,以西(昌)-攀(枝花)高速公路为背景,分析了山区道路工程建设环境背景条件,从道路沿线地质环境质量及道路工程建设对地质环境的影响因素的分析着手,研究了地质环境对山区道路工程的制约与影响、山区道路工程地质环境影响机制、道路工程与地质环境的相互作用及道路工程建设期间水土流失规律,建立了道路工程地质环境影响的评价指标体系和评价模型以及道路工程建设期间水土流失模型,提出了道路环境灾害防治对策。取得了如下研究成果：1、较为详细地分析了西(昌)-攀(枝花)高速公路所处区域的区域地质背景条件及道路沿线工程地质条件,认识到山区道路工程由于地质环境复杂,线路等级较低,施工条件差,加上施工不当等原因,使工程的抗灾能力低,山区道路工程具有明显的易损性。地质环境对山区道路工程的影响主要表现在：对线路走向的制约,对施工方法及施工条件的制约,对个体工程抗灾能力的要求高,对道路养护要求高。不同地质环境条件对道路工程影响的程度和方式不同。2、对道路工程建设环境影响机制进行了分析,道路工程对地质环境的影响体现在道路建设各阶段。例如,道路设计阶段,由于工程勘察的疏忽、选线及设计的不合理,均可造成各种短期的或潜在的地质环境影响和破坏；道路施工过程中,由于土石方工程的开挖、填筑及各种弃土的处治不当,将对地质环境产生严重影响。3、在道路沿线地质环境质量影响因素的分析研究的基础上,构建了包括地质构造、地形坡度、地层产状、地震、岩体结构、岩性组合、地质灾害等因素的地质环境质量评价指标体系；利用GIS数据库、层次分析模型、模糊综合评价模型等方法对西攀高速公路沿线2 km范围内地质环境质量进行了分区评价。4、通过道路工程建设对地质环境的影响机制分析,选择地质构造、地层产状、岩性组合和高填深挖等12个子因子,从地质体稳定性、岩土体稳定性、工程活动强度和地质灾害等4方面建立了公路工程对地质环境影响的评价指标体系和层次分析模型,利用GIS、模糊综合评判方法对公路工程建设对地质环境影响的程度进行了分区评价。5、对西昌-攀枝花高速公路不同下垫面边坡进行了天然降雨条件下水土流失观测试验,探讨了道路施工期不同人工边坡的土壤侵蚀规律并得到了施工期土壤侵蚀实验模型。实验结果表明：(1)高速公路建设期间不同人工地貌边坡水土流失主要以沟蚀为主,坡面冲刷物质大部分堆积在边坡坡脚(或边坡台阶)和施工便道上,随水流汇集到河网中的物质一般不超过侵蚀总量的10%。(2)路堤边坡土壤侵蚀强度主要影响因素为次半宽雨量,其侵蚀量及产沙量与次半宽雨量有较好的线性相关性；路堑边坡土壤侵蚀强度主要影响因素为次汇水面宽雨量,其侵蚀量及产沙量与次汇水面宽雨量有较好的线性相关性；具有汇水平台的弃土场边坡土壤侵蚀强度主要影响因素为次平台雨量,其侵蚀量及产沙量与次平台雨量有较好的线性相关性。(3)据初步实验研究结果,各种边坡的汇水面是影响土壤侵蚀的主要因素。因此,山区公路建设中作好各种汇水面的排水和防护是减少水土流失的重要措施。6、在分析了工程活动与地质环境相互作用机制基础上,探讨了道路工程与地质环境相互作用规律。分析了道路工程建设与地质环境之间的互馈关系。更多还原

【Abstract】 Environment impact assessment is an issue of important study of highway construction project for the sustainable development. The road engineering construction cannot leave certain natural environment, also especially is close to the geological environment relations. The road engineering construction and the geological environment detuning may cause geological environment’s aggravation, as well as the secondary geological disaster. Therefore, as to the complex west mountainous area that in exploitation of western China and the transportation demands rapid growth, strengthens to the mountain road engineering geological environmental effect mechanism research in order to control or the reduction of the secondary geological disaster and creates from it to the geological environment perturbation is imminent. As a consequence, this article combines with the Supported by National Science Foundation of China "the western region of major road projects and environmental interaction mechanism", take the XiPan highway as example, analysis the context of the conditions of the built environment in the mountain road engineering. We start from the geological environment quality and impact factors of road construction projects on the geological environmental along the road, study the impact and constraints of geological environment to mountain road engineering and the mountain road engineering’ mechanism of environment affection, road engineering and geo-environment interaction and soil erosion law during the road construction projects. It has obtained the following research results:(1) The regional geology background condition and the engineering geology condition along the route of the highway from Xichang to Panzhihua has been Analyzed in detail; Due to the complexity of the geological environment of mountain road engineering, lower grades of the line, and bad construction conditions, together with the misconduct in construction and other reasons, the withstand disaster capacity of the project becomes low, and make mountain road obviously vulnerable. The impact of geological environment on the mountain road engineering construction mainly reflected in the following respects: constraints on the alignment of road and methods of construction along with construction conditions, the high request of individual project’s requirements as well as the road maintenance requirements. Different geological environment conditions to different extent and in different ways affect the road engineering.(2) The environmental impact mechanism of the road construction has been analyzed. The impact of the road construction on geological environment reflects in various stages of road construction. Road design stage, as a result of the negligence of engineering investigations, unreasonable route selection and design may cause varieties of short-term or potential destruction of the geological environment; during road construction process, due to the excavation of rock and soil and road making, improper treatment of the waste soil, which will have a serious impact on the geological environment.(3) Based on analysis of geological environment quality influence factor along the Xichang-Panzhihua freeway line assessment index system and hierarchal analysis model for geological environment quality was established. In establishment of the system and model above, eight factors such as geological construction, rock composite and so on was selected; The assessment of geology environment quality along the 2km scope of Xichang-Pangzhuhua highway was carried out with fuzzy synthetic evaluation method and GIS database.(4) Based on analysis of geological environment and engineering construction activities along the Xichang-Panzhihua freeway line assessment index system and hierarchal analysis model for impact of highway engineering on geological environment was established in four aspects of ground stability, rock and soil mass stability, engineering activities and geological disaster. In establishment of the system and model above,12 factors such as geological construction, rock composite and so on was selected. The assessment of influence degree of highway construction on geological environment was carried out with fuzzy synthetic evaluation method and GIS.(5) In order to investigate the behavior of soil erosion on the slope of the different underlaying surface during construction, the experiment with natural rainfall on Xi chang-Pan zhihua highway was conducted, to quantify the runoff and soil loss. The results show that:①During the expressway construction, the main type of soil erosion is gully erosion. The majority down wash of sloping surfaces accumulate at the base of slope (or pedestal sit of slope) and the pavement. But the mass which flow into the river system generally does not exceed 10% of the whole amount of soil erosion.②The half-width precipitation are the principal factors that cause soil erosion on the slope of the embankment. The amount of erosion and sand output has good linearity relativity with the half-width precipitation. The catchment area precipitations are the principal factors that cause soil erosion on the cutting slope. The amount of erosion and sand output has good linearity relativity with the catchment area precipitation. The platform precipitations are the principal factors that cause soil erosion on the catchment platform of the dumped soil area slope. The amount of erosion and sand output has good linearity relativity with the platform precipitation.③The experimental model to predict soil erosion on the slope has guiding significance to water and soil conservation during highway construction. According to the preliminary experimental study result, the catchment surface is the principal factors that cause soil erosion on the slopes. The drainage of catchment surface is important measure of reduce soil erosion in mountainous area highway construction.(6) Based on interaction mechanism analysis of road engineering construction and geological environment, we inquire the interaction law of road projects and the geological environment. Road construction and geological environment are inter-relationship and influence each other; road geological disasters’ adverse effects on geological environment is the deterioration of the geological environment, so is the decline of environment quality; geological environment’ adverse effects on road geological disasters is the deterioration leads the road geological disasters increased, along with the frequency and intensity increased.更多还原