【作者】 许尚杰；

【导师】 党发宁；

【作者基本信息】 西安理工大学 ， 岩土工程， 2010， 博士

【摘要】 本文针对土坝的特点,在前人工作的基础上,把土坝的质量评价改为质量与使用寿命评价并举,把盲数理论与土坝安全耐久性分析有机结合,建立了适合土坝特点的耐久性评价体系、坝坡稳定性可靠度分析、渗透稳定性可信度评价分析、以浑水渗流理论为基础的浑水防渗措施等有关土坝的安全耐久性评价方法及工程应用,初步取得了以下成果：1、系统的论述了不确定性的分类,工程中的主要不确定性因素及其特点,有关不确定性的计算和评价方法,并阐述了盲信息和盲数理论,为盲数在土坝安全耐久性评价中的应用奠定了理论基础。2、搜集了国内外溃坝数据,详细分析了溃坝的原因,并以山东省土坝为基础对病害类型和现状进行了调查。认识到溃坝的规律和特点,对土坝的老化现状、病害类型有了一个明确的认识,为建立适合山东水库特点的土坝安全耐久性评价体系提供了基础资料。3、提出了以土坝的耐久性为评价标准的评价方法。该法以层次分析法原理为基础,以渐进性老化状况过程为评价依据,建立了老化系数与耐久性的关系,确立了土坝评价指标体系和指标的评价方法,并进行了指标量化,客观化,减少了人为的主观行为,得到的结果具有科学性、合理性和可比性。该法能较为客观地分析大坝的现状和未来的状态,并给出了耐久性评价值,便于工程的横向比较,为工程的质量评价开辟了一个新的途径。4、系统分析评价坝坡稳定的各种计算方法和特点,根据库水位骤降过程孔隙水压力的消散,非饱和土范围的变化对土体的抗剪强度的影响,提出采用基于有限元应力分析的圆弧滑动法对坝坡稳定进行分析,该法比较真实的反应滑面的应力状态,根据抗滑理论能容易建立起可靠度功能函数,把土坝边坡稳定的定值分析和可靠度分析有机结合,更易于坝坡稳定的评价分析。5、分析了基质吸力的影响因素、测量方法,建立了BP神经网络推求吸力内摩擦角的方法；采用盲数理论对抗剪强度试验数据进行整理和分析,即可提供丰富的试验数据,也避免了以往统计方法造成数据信息的丢失,为边坡稳定的可靠度分析提供基本数据。6、采用盲数理论对土坝的渗透稳定性进行评价分析,不但能清楚地知道渗透稳定性的安全程度,并且可知评判结果的可信程度,避免了平均意义的判断结果,使结论更加具有参考价值。本文把可信度理论渗透稳定性判定方法应用于工程实例,在观测资料的基础上评价了坝基管涌、坝后流土发生的可能性及其结论的可信程度,并用观测资料分析和反演计算两种方法预测了高水位的渗透稳定性,为土坝的渗透稳定评判提供了科学依据,因此可以说盲数理论为我们进行土坝渗透稳定性不确定性评价分析提供了一种切实可行的方法。7、从防渗措施的耐久性出发,详细论述了国内外防渗措施的研究现状,提出了基于浑水理论的浑水淤积层防渗措施。系统地分析了黄河泥沙物质组成的稳定性、下游引水的泥沙含量、颗粒组成随季节的变化规律,并进行了室内试验,验证了浑水淤积层的防渗性能。利用浑水渗流理论对库坝的渗漏量、浸润线的变化进行了理论分析,并应用于工程实践,证明利用引黄河浑水能形成一定厚度的淤积层作为库坝防渗的措施不仅能满足土坝的防渗要求且耐久性好,浑水防渗措施可为类似工程借鉴。更多还原

【Abstract】 According to the features of earth dams, on the basis of the previous worker’s work, this article changes the evaluation of quality into that of both quality and service life, and composing actively the blind number theory and safety and durability analysis, sets up safety durability evaluation methods and engineering applications on earth dam as durability evaluation system, reliability analysis of dam slope, reliability analysis and evaluation of seepage stability, seepage control method based on muddy water seepage theory, complying with the features of earth dams. And the following achievements at the first stage were made:1、This article stated the categories of uncertainties, the main uncertain factors and the features in the project, the calculation and evaluation method of the uncertainty and presented the blind information and blind number theory, building up the theory basis for the application of blind number in the evaluation of safety and durability.2、This article collected the data of dam breach at home and abroad, analyzed the reason of dam breach in detail and carried out the survey of disease type and existing condition based on the earth dams in Shan Dong Province. Realizing the rule and features of dam breach and having a common knowledge of the aging state of earth dams and the disease types, it provided basic materials for the construction of earth dams safety and durability evaluation system which complies with the features of reservoirs in Shan Dong Province.3、This article proposed the evaluation method which takes the durability of the earth dams as the evaluation standard. Basing on the analytic hierarchy process and taking the progressive aging condition and process as the rule, this method sets up the relationship between the aging coefficient and durability, establishes evaluation index system of earth dams and the evaluation method of index and carried out the quantification and objectification and reduced the personal subjective behavior, and the results are scientific, reasonable and comparable. This method analyzed objectively the existing and the future conditions of the dams and provided durability evaluation value for the cross comparing of the project and the open of a new method for the quality evaluation.4、This article analyzed systematically various calculation method and features of the evaluation of the stability of the dam slope, and proposed to apply circular slide method based on finite element stress analysis to the analysis of the stability of the dam slope, according to the extinction of pore water pressure in the rapid drawdown of the reservoir and the impact that the unsaturated soil has on the shearing strength of the soil. This method reflects the real force state of the slide surface. It is easy to set up reliability function according to antiskid system. It is easier to carry out the evaluation and analysis of the stability of the dam slope by combining the definite analysis with the reliability analysis of the stability of the earth dam side slope.5、This article analyzed the influencing factor and measuring method of the matrix suction and built up the method of using BP nerve network to find the angle of internal friction with respect to the matrix suction; applied blind number theory to reorganize and analyze the test data of shearing strength, then, rich test data can be provided and the lost of data caused by the previous statistical method can be avoided, providing basic data for the reliability analysis of the stability of the side slope.6、This article evaluated and analyzed the seepage stability of the earth dam with blind number theory, not only the safety degree of the seepage stability was clear, but the reliability degree of the evaluation result can be known, avoiding the average judging result and making the conclusion have more referencing value. This article applied the judging method of the reliability theory seepage stability to the example of the projects, evaluated the possibility of piping of the dam foundation and soil flowing at dam toe and the reliability of the conclusion on the base of the inspecting materials and predicted the seepage stability of the high water level with two methods of inspecting material analysis and inversion calculation, providing scientific rules for the judgment of the seepage stability of the earth dams. Thus, we can say that blind number theory provided an available method for the uncertainty evaluation and analysis of the seepage stability of the earth dam.7、This article discussed in detail the research condition of the impervious methods at home and abroad based on the durability of the impervious methods and stated the muddy water silting bed impervious methods based on the muddy water theory. This article analyzed systematically the stability of the composition of the soil of the Yellow River, the soil content of the lower river, the law of the particle composition changing with the seasons and carried out room test to verify the impervious performance of the muddy water silting bed. It analyzed the change of leakage and saturation line of the reservoir dam with the muddy water with Percolation Theory and exercised in the project. It was proved that using silted bed which wad made by the diversion of the muddy water of Yellow River as the impervious method of the reservoir dam not only can meet the impervious demand of the earth dam but also the durability is good. The muddy water impervious method can be learned by the similar projects. Key Words:Earth dam;blind number;stability;durability;seepage failure;muddy water theory;reliability This research is supported by the National Natural Science Foundation of China (50879069) This work was supported by the ministry of water resources public sector research and special(2007SHZ1-200701004) This research is supported by the National Natural Science Foundation of China (50679073) This research is supported by the National Natural Science Foundation of China (90510017)更多还原