关于调整博士学位论文送审方式的通知

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1 附件二 : 博士学位论文公示材料学生姓名于建军学号二级学科结构工程导师姓名王连广论文题目预应力冷弯 U 型钢 - 混凝土组合梁试验与理论研究论文关键词冷弯 U 型钢 ; 预应力组合梁 ; 承载力与变形 ; 界面滑移 ; 剪力滞效应 ; 非线性分析论文摘要 ( 中文 ) 预应力冷弯 U 型钢与混凝土组合梁是通过剪力连接件将冷弯 U 型钢梁与混凝土连接起来并施加预应力的一种组合梁, 这种组合梁除了具有能充分利用钢所具有的优越抗拉性能和混凝土所具有的优越抗压性能优点外, 还有施工方便适应性强节省材料, 降低工程造价等突出优点目前, 国内外对普通钢与混凝土组合梁的力学行为做了相当研究, 而对轻型钢与混凝土组合梁的力学行为研究相对较少, 特别是, 对预应力冷弯型钢与混凝土组合梁的受力性能研究更为少见本文采用试验研究理论分析及计算机模拟相结合的方法, 研究预应力冷弯 U 型钢与混凝土组合梁的力学性能通过试验, 研究预应力冷弯 U 型钢与混凝土组合梁的工作机理和破坏模式, 试验结果表明 : 承受正弯矩作用的冷弯 U 型钢与混凝土组合梁和预应力冷弯 U 型钢与混凝土组合梁均以受拉钢板屈服和受压区混凝土压碎为破坏特征试件的荷载与变形关系呈现直线的弹性微弯曲的弹塑性及直线的强化三个阶段, 两种组合梁的受力性能均良好 ; 承受负弯矩作用的预应力冷弯 U 型钢与混凝土组合梁中混凝土板开裂比较早, 在接近极限状态时, 跨中钢板出现局部屈曲, 上 ( 下 ) 翼缘均屈服, 而钢梁腹板未屈服, 混凝土板顶面裂缝主要分布在荷载作用点附近 ; 预应力冷弯 U 型钢与混凝土连续组合梁, 混凝土裂缝首先出现中支座附近, 在极限状态时, 组合梁以部分混凝土压碎和受拉钢屈服为破坏特征, 跨中变形较小, 钢梁上翼缘均未屈服, 钢梁下翼缘屈服 ; 在整个受力过程中, 所有试验试件中的预应力筋均处在弹性工作阶段, 没有达到极限抗拉强度针对预应力冷弯 U 型钢与混凝土组合梁的结构特性, 分别给出了无粘结预应力和有粘结预应力组合梁不同受力阶段的截面应力和极限抗弯承载力计算公式, 理论公式计算结果与试验结果吻合良好利用弹性理论与变分理论, 建立了预应力冷弯 U 型钢与混凝土组合梁的界面滑移截面轴向力和变形计算公式, 计算结果表明 : 对称集中荷载和均布荷载作用下的组合梁界面相对滑移截面轴向力沿梁长分布规律类似界面连接刚度对组合梁的界面滑移 ( 轴向力 ) 影响较大, 钢板厚度和预应力增量对组合梁的界面滑移 ( 轴向力 ) 影响不是很明显利用纤维模量法, 编制预应力冷弯 U 型钢与混凝土组合梁非线性分析程序, 计算结果表明, 钢板厚度混凝土强度等级钢梁下翼缘宽度及预应力度等参数对预应力组合梁的承载能力和刚度影响较大, 而混凝土翼缘板的宽度和厚度对组合梁的承载能力和刚度影响不明显依据能量变分理论, 建立了基于不同位移函数的预应力组合梁的剪力滞效应位移控制方程, 给出不同荷载下的位移和应力的计算公式计算结果表明, 在集中荷载作用下, 简支组合梁剪力滞效应仅对沿跨径方向局部段有影响, 作用点越靠近支座处剪力滞效应越大 ; 在均布荷载作用下, 剪力滞效应主要出现在支座处, 剪力滞系数由支座向跨中逐渐减小 ; 组合梁的跨宽比和宽高比对剪力滞系数影响较大, 钢腹板厚度对腹板区内的混凝土翼缘板剪力滞系数有明显影响 ; 混凝土翼缘板悬臂长度腹板倾斜度混凝土翼缘板厚度和钢翼缘板厚度对剪力滞系数的影响不明显利用有限元软件 ABAQUS, 建立了适合于预应力 U 型钢与混凝土组合梁的有限元计算模型, 计算结果表明, 组合梁的混凝土板和受拉钢梁翼缘板的应力沿宽度分布不均匀, 但是, 钢梁受拉翼缘的应力分布相对混凝土翼缘板较为均匀, 腹板位置附近的混凝土板应力较大 ; 组合梁跨中截面应力明显高于四分之一和八分之一截面 ; 集中荷载越接近支座, 剪力滞系数越大, 并且, 剪力滞效应影响组合梁的范围较小 ; 宽跨比对剪力滞效应的影响较明显, 宽跨比越大, 剪力滞效应越明显 ; 悬臂长度与腹板倾斜度对剪力滞效应有一定的影响, 并且对钢梁下翼板影响较混凝土翼板更为明显 2

2 论文摘要 ( 英文 ) Prestressed composite girder of cold-formed steel U sections and concrete is a type of the composite girders which connects the cold U-formed steel to the concrete by shear connectors and then applies prestress to the girder. This type of composite girder has many advantages include full use of the tensile property of steel and the compressive property of concrete, construction conveniently, strong adaptability, saving material, reducing engineering cost and so on. At present, there are many researches on the mechanical behavior of steel and concrete composite girders, but there are a few of studies on the mechanical behavior of formed steel and concrete composite girders, especially on the prestressed composite girders of cold-formed steel U sections and concrete. This paper used experimental study, theoretical analysis and computer simulation to study the mechanical properties of prestressed composite girder of cold-formed steel U sections and concrete. Through experiments, the working mechanism and failure mode of prestressed composite girder of cold-formed steel U sections and concrete were studied. The results showed that the failure modes of composite girder of cold-formed steel U sections and concrete and prestressed composite girder of cold-formed steel U sections and concrete were both concrete being crushed. Load and deformation relationship of the specimens showed linear elasticity, slightly curved elastic-plastic and linear strengthening. The mechanical behavious of two kinds of composite girders were good. The concrete slab of prestressed composite girder of cold-formed steel U sections and concrete appeared cracks early. When the load reached the ultimate load, the medium steel plate appeared buckling partly, the top and bottom flange plates both yielded, but the web didn t yield, the top cracks of the concrete slab distributed near the load point. As for the prestressed cold-formed steel U sections and concrete continuous composite girders, the cracks of the concrete slab appeared near the intermediate support. When the load reached the ultimate load, the failure modes were concrete being crushed and steel plate yielded. The mid-span deformation was small. The top flange plate didn t yield, but the bottom flange plate yielded. All tendons of specimens were in the state of elasticity in the test. According to structural characteristics of prestressed composite girder of cold-formed steel U sections and concrete, the formulars of strain and ultimate bearing capacity of prestressed composite girders with prestress without bond or prestress with bond were presented. The calculated results agreed well with the test ones. 3

3 The formulars of interface slip, axial force and deformation of prestressed composite girder of cold-formed steel U sections and concrete were presented according to elastic theory and variation theroy. The results showed that the regulars of interface slip and axial force along the length of the girders were similar under symmetric concentrate load and distributed load. The interface coupling stiffness had significantly effect on the interface slip. The thickness of steel plate and the increment of pretress had a little effect on the interface slip. According to the fiber modulus method, nonlinear analysis of prestressed composite girder of cold-formed steel U sections and concrete was estabilshed. The results showed that the thickness of steel plate, the strength grade of concrete, the width of under flange of steel plate and the pretress had significantly effect on carrying capacity and stiffness. But the width and thickness of concrete slab had a little effect on carrying capacity and stiffness. By energy variational principle, the deformation control formula of prestressed composite girders shear lag effect based on different deformation function was established. The calculation formula of deformation and stress under different load was presented. The results showed that under concentrated load, the shear lag effect of simply supported composite girders only affected the local section along the span direction. When the load point closed to the support, the shear lag effect researched maximum. Under distributed load, the shear lag effect was mainly appeared in the support. The shear lag coefficient decreased from support to mid-span. The width-span ratio and width-height ratio of composite girders had great influence on shear lag coefficient. The thickness of the steel web had significant effect on the shear lag coefficient of concrete flange in web zone. The cantilever length, the web inclination, the thickness of the concrete flange and steel flange thickness had little effect on the shear lag coefficient. Using finite element software ABAQUS, the model of prestressed composite girder of cold-formed steel U sections and concrete was established. The results showed that the stress distribution of concrete and tensile flange of steel beam was not uniform along the width. However, compared with concrete flange, the stress distribution of tensile steel girder flange was uniform. The stress of concrete slab which was nearby the web location was larger. The stress of composite girder in mid-span section was significantly higher than that in quarter section and that in one eighth section. When the concentrated load point closed to the support, the shear lag effect coefficient researched maximum. Shear lag effect little affected the scope of composite girder. The width-span ratio affected the shear lag effect obviously. The shear lag effect increased with the 4

4 increment of width-span ratio The cantilever length and the web inclination had certain influence on the shear lag effect, and that impact on the bottom flange of steel beam were more apparent than concrete. 5

5 论文主要创新点 1. 完成承受正弯矩作用的 ( 预应力 ) 冷弯 U 型钢与混凝土组合梁承受负弯矩作用的预应力冷弯 U 型钢与混凝土组合梁及预应力冷弯 U 型钢与混凝土连续组合梁的试验研究, 重点研究其工作机理混凝土裂缝变化应变分布及破坏模式 2. 利用弹性理论, 建立了预应力冷弯 U 型钢与混凝土组合梁的界面滑移和截面轴向力计算公式, 并计算主要设计参数对界面滑移和截面轴向力的影响依据附加变形法弹性理论法及变分理论, 建立了可以充分考虑界面相对滑移和预应力度影响的预应力冷弯 U 型钢与混凝土组合梁的变形计算公式 3. 依据能量变分理论, 建立了基于不同位移函数的预应力组合梁的剪力滞效应位移控制方程, 给出不同荷载下的位移和应力的计算公式计算分析了主要设计参数对剪力滞系数的影响 4. 利用纤维模量法, 编制预应力冷弯 U 型钢与混凝土组合梁非线性分析程序, 计算计算主要设计参数对组合梁的承载能力和刚度影响利用有限元软件 ABAQUS, 建立了适合于预应力 U 型钢与混凝土组合梁的计算模型, 计算分析组合梁中混凝土翼缘板和钢梁受拉翼缘的应力分布及主要设计参数对其影响攻读博士期间取得的学术成果注 : 按有关规范填写本人为第一作者或导师是第一作者本人为第二作者, 且第一署名单位为东北大学的研究成果 1 预应力冷弯 U 型钢与混凝土组合梁变形计算, 哈尔滨工业大学学报,2012( 增 ) [ 第 4 章 ] 2 Axial force of prestressed composite girders with steel U-shape girders under uniformly distributed load, Beijing: 9th International Conference on STEEL, SPACE & COMPOSITE TRUCTURES, 2007.(EI 收入 ) 3 预应力 U 型钢与混凝土组合梁滑移计算, 哈尔滨工业大学学报,2011( 增 ) [ 第 4 章 ] 4 基于能量法的悬臂金属拱型波纹屋面的剪力滞分析, 钢结构,2010(11) 5 基于能量法的冷弯 U 型钢与混凝土组合梁界面剪力分析, 沈阳建筑大学学报,2010(1)[ 第 6 章 ] 6 无粘结预应力 U 型钢梁与混凝土简支组合梁抗弯性能, 建筑技术,2007(10) [ 第 3 章 ] 7 大跨度预应力型钢与高强混凝土组合梁桥关键技术研究, 辽宁省科学技术奖三等奖,2013 年, 排名 : 第一 8 新型 GFRP 管钢骨高强混土组合构件关键技术研究, 辽宁省科学技术奖二等奖,2010 年, 排名 : 第四 9 客运专线 CRTSⅢ 型无碴轨道混凝土轨道板预制施工综合技术, 沈阳科学技术奖一等奖, 辽宁省科学技术奖三等奖,2013 年, 排名 : 第六 6

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Maup re,,,,,, ;,,,,,,,,,, PC 1985 Cognac,, 80, [ 526 ], 420m 160m [ 728 ], PC,,,,,,,,, , [ 3 ] 3008mm, 488mm, 222mm, ( ) 2880mm , 4914, 6 29 1 Vol129, No11 2008 2 Journal of Building Structures Feb1 2008 : 100026869 (2008) 0120075208, (, 350002) :, 3,,, ;, ; : ; ; ; ; : TU39819 TU31711 : A Experimental studies on concrete filled steel tubular