湖南大学博士学位论文砌体结构基本受力性能的研究姓名：刘桂秋申请学位级别：博士专业：结构工程指导教师：施楚贤20050416博士学位论文 I摘 要 本文综述国内外砌体结构基本理论的研究现状和发展趋势，对砌体受压本构关系、破坏准则、受压及受剪性能进行了较系统的研究。 通过对国内外学者提出的不同受压本构关系进行比较和分析，提出了包括砖砌体和混凝土砌块砌体在内的受压本构关系表达式，首次给出了合理的对应于峰值应力的应变0与极限压应变u的比值。简化了 M.J.N. Priestley 等提出的无约束混凝土砌块砌体本构关系下降段的下降斜率表达式，简化后的表达式更直观、简单。根据本文提出的砌体受压本构关系，块体、砂浆、砌体变形协调条件以及砌体弹性模量实测结果统计，采用这三种方法推导得到砌体弹性模量表达式，并由实测结果经统计回归得到砖、砌块、砂浆弹性模量的表达式。 依据库仑理论、主拉应力以及主压应力强度理论，首次在国内较系统地建立了剪压状态下砌体的破坏准则，该准则能反映剪压状态下砌体可能出现的三种破坏，并明确提出了划分滑移破坏、受拉破坏及受压破坏的界限值。该破坏准则能反映不同受力阶段竖向压应力对砌体抗剪强度的影响规律，由该破坏准则推导的砌体抗剪强度计算值不仅与试验结果吻合较好，而且与骆万康提出的相关曲线基本吻合。 本文从砌体受压时的平衡条件、变形协调条件以及破坏准则建立了包括砖砌体、未灌芯和灌芯混凝土砌块砌体在内的砌体抗压强度计算公式，该公式较全面反映了块体、砂浆、灌芯混凝土的强度、弹性模量、泊松比、几何尺寸对砌体抗压强度的影响；简化后的计算公式形式简单，改进了现行规范计算公式不连续、计算方法烦琐等存在问题。简化后的计算结果与试验结果、规范取值吻合良好。 本文分析并总结了影响砌体剪力墙抗剪性能的主要因素；利用 ALGOR FEA软件和本文建立的剪压状态下砌体破坏准则，分析了无洞及开洞墙的开裂荷载、裂缝分布及其出现的顺序。采用 MSC. Marc 软件并选用二维的四节点单元和本文提出的砌体受压本构关系、砌体破坏准则对砌体剪力墙受力及变形进行弹塑性有限元分析，墙体开裂荷载、极限抗剪承载力以及对应的墙顶最大水平位移预测值与实测值吻合较好。在国内外较全面、系统地建立了无洞、开洞及无筋与水平配筋砌体剪力墙的抗剪承载力计算公式。该公式考虑了影响墙体抗剪承载力的主要因素，力学概念清楚，满足无洞、开洞及无筋与水平配筋砌体剪力墙的边界条件，具有连续性，计算方法简单、便于应用；并弥补了现行规范未考虑墙体高宽比影响的不足，扩大竖向压应力较大时的应用范围。本文提出了提高墙体裂后变形能力及维持墙体整体性所需的水平钢筋最小配筋率。 关键词：本构关系；破坏准则；受压性能；受剪性能；弹塑性有限元分析 砌体结构基本受力性能的研究 IIAbstract The current situation and developing trend of research on the basic theory of masonry structure at home and abroad are summarized. The compressive stress-strain relations, failure criteria, compressive and shear behavior of masonry are studied systematically. The expressions of compressive stress-strain complete curve with inclusion of brick and concrete block masonry have been put forward through comparison and analysis of different compressive constitutive relations put forward by scholars at home and abroad. The reasonable ratio u0/ is provided for the first time, which equals to 1.6 for brick masonry, 4.0 for concrete block masonry. The expression of descending slope of descending stage provided by M.J.N. Priestley is simplified by this paper. The simplified expression is more audio-visual and simple. Three kinds of expressions of masonry elastic modulus are derived on the basis of the compressive stress-strain relation of masonry put forward by myself, deformation coordination among block, mortar and masonry and the experimental results statistic of masonry elastic modulus. The formulae of elastic modulus of brick, block and mortar are also derived on the basis of statistic regression of testing results. The failure criteria of masonry have been founded systematically at home for the first time according to Mohr-Coulomb theory, principal tensile and compressive theory. These failure criteria can reflect probable three kinds of destruction of masonry in compression-shear, in the meanwhile provide definitely boundary values to divide failure modes of slipping, tensile and compressive failure. These failure criteria bring to light the failure mechanism and influencing law of vertical compressive stress on shear strength of masonry. The calculating values of shear strength of masonry derived from these failure criteria not only agree well with experimental results, but also coincide with the interrelationship curves basically put forward by Luo WanKang. The calculating formulae of compressive strength of masonry are founded on the basis of equilibrium condition, deformation coordination and failure criteria with inclusion of brick, ungrouted and grouted concrete block masonry. These formulae reflect more comprehensively influences of strength, elastic modulus, Poisson ratio of block, mortar, grout concrete on masonry compressive strength. The form of 博士学位论文 IIIcalculating formulae simplified is simple. This method improves existing questions of current code such as uncontinuity of formulae and troublesomeness of calculating method. The main influencing factors on shear behavior of masonry shear wall are analyzed and summarized. The cracking load, crack distribution and its appearance sequence of wall with or without holes are analyzed using ALGOR FEA software and the failure criteria of masonry in compression-shear founded by this paper. The elasto- plastic finite element analysis on the force and deformation of masonry shear wall has been made by using MSC. Marc software and adopting two-dimensional four-node element, compressive stress-strain relation and failure criteria of masonry put forward by this paper. The predicted values of cracking load, ultimate shear load-bearing capacity and maximum horizontal deformation of wall agree better with testing results. The calculating formulae of shear load-bearing capacity of unreinforced and reinforced masonry shear wall with or without holes have been founded more comprehensively and systematically at home and abroad for the first time in which main influencing factors on shear load-bearing capacity of wall are considered. These formulae are successive and boundary condition can be satisfied. The method is clear, simple and easy to be applied. It also compensate incompleteness of current code in which th