【作者】 唐晓玲；

【导师】 黄质宏； 严景明；

【作者基本信息】 贵州大学 ， 矿业工程， 2007， 硕士

【摘要】 粉煤灰是燃煤发电过程中的副产品，世界上每年粉煤灰的排放总量估计高达10亿多吨，仅我国粉煤灰的年排放总量目前已达到1.8亿吨以上，而且还在不断增长，目前我国虽然已着手进行粉煤灰的综合利用，但年利用量不及年排放量的40％，因此电厂只能通过修筑贮灰坝来存放粉煤灰。贮灰坝是火电厂的重要组成部分，随着电厂规模的不断扩大，要求贮灰场的库容量也不断增加，相应的贮灰坝也愈建愈高，和水利工程中的拦水大坝相比较，粉煤灰灰坝等固体渣坝的设计技术、施工质量控制，运行管理水平还有一定差距，致使灰场溃坝事故时有发生，给国家和人民的生命财产造成重大损失。可以这样说，贮灰坝的安全与否关系重大，对贮灰坝运行是否稳定的评价也至关重要。粉煤灰的物理力学特性决定了灰坝的安全，与贮灰场的渗流分布密切相关，渗流稳定问题解决不好，将导致不可估量的损失。因此只有深入分析贮灰场的渗流分布，才能确保灰坝安全，确定合适灰坝型式、排渗设施及其合理尺寸。本文以某发电厂燃煤锅炉所排放的粉煤灰为试验研究对象，通过级配、击实、直剪、三轴剪切试验和现场碾压试验，对其物理力学性质及其影响因素作了较为细致的分析和研究，并对灰坝的渗流及稳定进行计算分析，期望为灰坝的设计、施工和运行提供可靠的依据。本论文的主要内容有：1、粉煤灰物理力学指标的确定。本文通过对某发电厂粉煤灰的室内土工试验和现场碾压试验，确定其粉煤灰物理力学指标，为灰坝的渗流、稳定计算提供参数。2、灰坝的渗流计算。本文利用有限元计算软件，对灰坝及灰场内的饱和—非饱和渗流场进行了分析计算，确定浸润线位置、渗流自由面及渗流逸出点位置，分析影响贮灰场渗流分布的主要因素，提出了可供工程借鉴的建议，以期对灰坝设计、灰场建设及运行管理有所帮助。3、灰坝坝体的静力稳定分析。采用理正计算软件对灰坝进行稳定计算分析，确定灰坝在不同工况下的安全系数，为灰坝的设计、施工提供参考。更多还原

【Abstract】 Fly ash is the by-product in the process of coal-burning power generation. The total amount of the fly ash discharged in the world is estimated up to 1 billion tons every year. Only in our country the total annual amount has reached over 0.18 billion tons, and is still increasing continuously. Our country has already begun the comprehensive exploitation of the fly ash, but the annual utilization accounts for 40% less than the annual discharge amount. Therefore power plants can only construct ash dams in order to store fly ash.Ash dams are an important part of thermal power generation station. With power plant scale enlarging continuously, the ash storage capacity needs to increase and the height of corresponding storing ash dams also grows continuously. Compared with the water dams in hydraulic engineering, there is still a difference in the technical design of the solid residue, construction quality control, management level of fly ash, which causes occasional collapses of ash fields and causes heavy losses to the people’s lives and property. The safety of ash dams is of great importance, so is the steady appraisement on operations of ash dams.The physical mechanics characteristic of fly ash decides the safety of ash dams, which is closely related to the seepage distribution of ash fields. If the problems of the stable seepage cannot be resolved well, it will cause immeasurable losses. Therefore only thorough analysis on the distribution of the seepage of ash fields can insure the safety of ash dams and decide suitable pattern, seepage facilities and reasonable size for ash dams.This text takes fly ash discharged from a coal boiler in some power plant for the object of study, making careful analysis and study on physical mechanics property and its modifying factors and carrying on calculation and analysis of the seepage and stability of ash dams in the hope that it can provide a dependable basis available for the design, construction and operation of ash dams.The main contents of this thesis include:1. The determination of physical mechanics index of fly ash. Through the experiments, this text decides its physical mechanics index to provide parameter for the seepage and stable calculation of ash dams.2. The calculation of the seepage of ash dams. This text makes use of finite element calculating software, analyzing and calculating the saturated and semi-saturated seepage field in ash dams, determining the position of saturation line, analyzing the main factor influencing the distribution of the seepage in ash dams and providing the suggestion in the hope that it can be helpful to the design, construction and management of ash dams.3. The analyses on the static stability. Using computer software to calculate and analyze the static stability of ash dams, to give the safety coefficient of ash dams in different operating conditions and provide references for its design and construction.更多还原