基于可拓学的公路边坡稳定性评价与防治策略研究
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摘要
随着我国山区高等级公路建设的发展,复杂高边坡稳定性评价问题以及边坡治理中的各种矛盾问题日益突出。由于边坡工程是复杂的系统工程,这些问题难以运用单一学科的理论与方法来解决,这已成为边坡工程研究者的共识。为了从新的角度来探索和解决这些问题,本文引入可拓理论,从复杂公路边坡稳定性评价和边坡工程防治中矛盾问题的处理策略两大方面进行了研究。主要工作和研究成果如下:
     (1)将公路边坡工程学与可拓学结合起来进行研究,对公路边坡工程可拓设计进行了定义,通过对诸多实例的分析研究,归纳总结了基元的发散分析、相关分析、蕴含分析、可扩分析、共轭分析、可拓变换等原理,以及菱形、传导、逆向、共轭等思维模式在公路边坡工程设计中的应用方法,从而初步构建了公路边坡工程可拓设计的基本方法体系。
     (2)将公路边坡工程学和基元的相关分析原理、蕴含分析原理结合起来,建立了一般条件下的公路边坡稳定性相关网和蕴含系,为特定边坡的分析提供了一个基础模型。相关网和蕴含系是辅助分析边坡稳定性和边坡治理中矛盾问题求解思路的有效工具,对于待分析边坡,根据其具体工程条件和特征,在此基础模型上进行基元的适当增减就可以形成新的相关网和蕴含系。
     (3)基于可拓学的基元理论和关联函数理论,分析了边坡稳定性评价指标的选取原则、关联函数的选用方法,计算关联度时最优点的确定原则,并引入边坡工程可拓设计方法体系中基元的相关分析和蕴含分析方法,提出了一套“用综合关联度确定边坡稳定等级——用相关网辅助分析边坡失稳机制——用蕴含系辅助分析保证边坡稳定的措施”的公路复杂边坡稳定性综合评价方法体系。这种方法具有评价过程形式化、可传达性好、逻辑性强等优点,边坡稳定性相关网与蕴含系的引入,为分析边坡可能的破坏机制和保证边坡稳定的方法提供了一种形式化、易描述、有条理、能运算的有效工具。
     (4)分析了公路边坡治理中常见的目标、条件及其界定方法,边坡工程防治中矛盾问题及其核问题界定时的注意事项。结合公路边坡工程的特点,提出了求解公路边坡治理中不相容问题的可拓策略生成方法与流程、求解对立问题的转换桥构造方法与流程,并分析了原来的问题解决以后,由基元的相关性产生的传导矛盾问题。
     (5)将本文提出的边坡稳定性综合评价方法和求解边坡治理中矛盾问题的策略应用于云南某高速公路边坡工程中。通过综合关联度的计算,确定了边坡稳定等级,用相关网方法分析了边坡可能的破坏机制,用蕴含系方法分析了保证边坡稳定的措施,所得结论与边坡实际情况相符。针对边坡治理中出现的矛盾问题,对目标、条件和问题进行了界定,用本文所提出的方法求解了该问题,给出了解决矛盾问题的多种方案,验证了所提出方法的正确性和可操作性。
     可拓方法用形式化的模型表达各种信息元,并将其置于可描述,可运算,可拓展,可收敛,可变换的环境中,从而用以分析和解决矛盾(或创意)问题。在提倡新理念公路设计的背景下,基于可拓学的公路边坡稳定性评价方法与边坡治理中矛盾问题的求解方法,对于科学地评价复杂公路边坡的稳定性,以及解决边坡治理中的矛盾问题,形成边坡工程中的各种设计新理念、新方法、施工新技术、新工艺都具有重大的实用价值。
Problems of complex high slope stability evaluation and contradictory problems in slopecontrol become increasingly serious as high-grade highway construction in mountain areas isdeveloping in our country. It becomes a consensus that these problems can’t be sloved by usingsingle discipline easily because slope engineering is complex system engineering. In order toexplore and slove these problems from a new perspective, the author introduces extensiontheory to study complex highway slope stability evaluation and processing strategy ofcontradiction problems in slope prevention. The main results of the study are as follows:
     (1)Integrating Highway Slope Engineering with Extenics, the definition of extensiondesign on highway slope engineering was given in this thesis, application methods of basicelement analysis principle, extension transformation principle and extension thinking mode tohighway slope design were also summarized by researching large quantity of examples, thusbuilt basic method system of extension design on highway slope engineering preliminarily.
     (2)Net of relationships and implication system about highway slope stability under generalconditions were established in order to provide a basic model to analyze certain slope byintegrating Highway Slope Engineering with correlation analysis principle and implicationprinciple. Net of relationships and implication system are effective assistant tools for analyzingslope stability and solutions about contradictory problems in slope control, for a certain slope,new net of relationships and implication system could be formed based on this model accordingto its actual engineering conditions and features.
     (3)Based on basic element theory and dependent function theory of Extenics, selectingprinciple of evaluation index in slope stability, selecting method of dependent function,determination principle of optimal point when calculating relational grade were analyzed, bythe introduction of correlation analysis and implication analysis method in extension design onhighway slope engineering, a set of comprehensive evaluation method of complex highwayslope stability as "determine slope stability grade using comprehensive relational grade, analyzeinstability mechanism using net of relationships assistantly, analyze assurance measures ofslope stability using implication system assistantly" was proposed in this thesis. This methodhas advantages of formalization, communicableness and strong logicality, etc. An effective toolwhich was formalized, expressive, methodic, and countable was provided to analyze failuremechanism of slopes and ways to keep them stable by introducing net of relationships andimplication system about slope stability.
     (4)Usual goals, conditions and their definition methods in highway slope control, pointsfor attention in definition of contradictory problem and its core problem were analyzed. Bycombining features of highway slope engineering, the extension strategy generating method andprocess for solving incompatibility problem, transforming bridge construction method andprocess for solving opposite problem were proposed, and conductive contradictory problems caused by correlation among basic elements after initial problem solving were also analyzed inthis thesis.
     (5)Correctness and operability of the forementioned slope stability evaluation method andstrategy for solving contradictory problems were verified by applying them to certainexpressway slopes in Yunnan Province. Slope stability grade was determined by calculatingcomprehensive relational grade, instability mechanism was analyzed by using method of net ofrelationships, and assurance measures of slope stability were also analyzed using implicationsystem method, these analysises had the same results as the fact. Goals, conditions and theproblem were defined about the contradictory problem in slope control, and solutions weregiven by using forementioned solving method.
     Extension method expresses information elements by formalized models, and leaves themunder expressive, communicable, extensionable, polymerizable and transformable circumstancethereby analyzes and solves contradictory (or creative) problems. Against the backgroundwhich new concept highway design is advocated, slope stability evaluation method and solvingmethod to contradictory problems based on Extenics have great practical value in slopeengineering on evaluating stability of complex slope scientifically, solving contradictoryproblems in slope control, and forming new design concepts, new methods, new techniques andtechnology.
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