【作者】 王国光；

【导师】 龚晓南；

【作者基本信息】 浙江大学 ， 岩土工程， 2002， 博士

【摘要】 对于土、岩石和陶瓷等工程材料，在受拉和受压时表现出不同的性能，抗拉强度与抗压强度相差悬殊，抗拉弹性模量和抗压弹性模量也是不同的。经典弹性理论无法考虑材料的这种特殊性质。对于涉及这种材料的问题，如果延用经典弹性理论的解答，有可能产生较大的误差。为了有效解决拉压性能不同材料的工程问题，对拉压性能不同理论的研究具有重要的意义。 半无限空间内部作用竖向集中力问题是弹性理论的典型问题，经典弹性理论的解答即Mindlin解在解决工程问题时得到了广泛的应用。本文考虑材料的拉压性能不同的特点，对半无限空间内部作用竖向集中力问题进行了新的研究，做了如下工作： (1)引入Heaviside函数，建立了不能承受拉应力材料的弹性理论解； (2)基于不能承受拉应力材料的弹性理论解和Mindlin解，建立了拉压模量不同材料的弹性理论解； (3)将拉压模量不同材料的弹性理论解应用于桩基应力分析； (4)将拉压模量不同材料的弹性理论解应用于桩基沉降分析。 应用表明，基于拉压模量不同弹性理论解的桩基分析方法给出了合乎实际的规律性分析，同时对已有计算方法出现的问题作出了合理的解释。可以认为，拉压模量不同是土的重要性质，拉压模量不同弹性理论解答的提出是合理的。基于拉压模量不同弹性理论解的方法能够合理解决桩基沉降计算问题，而且对岩土工程其它问题和其他领域工程问题也有广阔的应用前景。更多还原

【Abstract】 Such engineering materials as soil,rock and porcelain,they present different properties in tension and compression. Not only their strengths but also elastic moduli are not equal. These properties are beyond the research of classic theory of elasticity. The errors may be not allowable if theory of elasticity is employed in the problems concerning these materials. The study on theory with different properties in tension and compression is important to engineering practice.Vertical concentrated load acting into semi-infinite elastic body is a basic problem in theory of elasticity. Mindlin’s solution is used broadly to solve engineering problems. This paper focuses on the problem of semi-infinite elastic body filled with the material which behaves differently in tension and compression. The contents include:(1) The solution of elasticity theory for the material incapable in tension is established by introducing Heaviside function;(2) The solution of elasticity theory with different modulus in tension and compression is established based on the solution of elasticity theory for the material incapable in tension and Mindlin’s solution;(3) The solution of elasticity theory with different modulus in tension and compression is employed to analyze the stress of pile foundation;(4) The solution of elasticity theory with different modulus in tension and compression is employed to analyze the settlement of pile foundation.The applications in analysis of pile foundation show that the method based on the solution of elasticity theory with different modulus in tension and compression gives reasonable results and the method can explain the questions of some methods in existence logically. It can be concluded that difference between tensile modulus and compressive modulus is an important property of soil and the solution of elasticity theory with different modulus in tension and compression is necessary and reasonable. The method based on the solution of elasticity theory with different modulus in tension and compression not only solves the problem of settlement calculation of pile foundation,but also can play an important role in other engineering field.更多还原