【作者】 张国军；

【导师】 刘伯权； 白国良；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2003， 博士

【摘要】 在大型火力发电厂主厂房结构中，由于其高度较大，且竖向荷载较大(如层间布置有煤斗等质量过于集中的设备)，故抗震问题较为突出。纵、横向框架柱具有与一般框架柱不同的特点，如柱截面高宽比较大，且承受很大的竖向荷载，其轴压比设计问题是柱设计的一个非常重要的因素。经常出现的情况是：框架柱的断面由轴压比限值确定，而框架柱的配筋由构造配筋率决定，这其中存在着不合理的地方。应用高强混凝土可以显著减小构件的截面尺寸，减轻结构自重和钢筋用量，具有明显优点，可获得较高的经济效益。但高强混凝土的脆性引起人们对其用于抗震结构的担心，强度等级愈高，胞性愈大。因此，在大型火力发电厂主厂房结构框架柱中应用高强混凝土，需研究改善高强混凝土柱抗震变形能力的有效措施。本文主要研究的内容有： (1) 首次针对火电厂主厂房结构框架柱的特点，对9个高轴压比高强混凝土框架柱和6个高轴压比普通混凝土框架长柱进行了低周反复水平加载试验，获得混凝土等级、轴压比、长细比、配箍形式及配筋率等对框架柱的抗弯及抗剪承载力、抗震变形能力的影响因素。在试验研究的基础上，提出高强混凝土框架柱正截面和斜截面承载力计算的建议公式，且给出了满足延性要求的C60混凝土框架柱轴压比限值和箍筋加密区箍筋的最小体积配箍率。 (2) 在试验研究和理论推导的基础上，给出了高轴压比下框架柱恢复力模型的骨架曲线，与试验骨架曲线吻合较好。为高强混凝土整体结构抗震性能和动力反应计算提供基础资料和依据。 (3) 混凝土用三维实体单元、钢筋用空间杆单元对钢筋混凝土框架柱进行三维建摸，而且同时考虑了钢筋和混凝土的粘结性能，通过合理的单元选取、网格划分及荷载步的确定，模拟了单调荷载作用下钢筋混凝土框架柱的荷载啦移曲线、开裂荷载、屈服荷载及最大荷载、裂缝发展规律、计算破坏裂缝图，并与相应的试验结果进行了比较分析。在有限元模拟试验框架柱的基础上，还对未做试验的框架柱进行了骨架曲线的模拟，从而对影响框架柱的各因素进行了综合分析。 (4) 计算出高强混凝土试验框架柱的累积滞回耗能随加载循环水平的变化，通过对各损伤模型的比较分析，提出了高强混凝土框架柱的损伤模型，为进一步进行损伤分析打下了良好的基础。更多还原

【Abstract】 In the main factory building structure of large-scale thermal power plants, due to its great height and large vertical loads (such as a furnished for arranging coal bucket between interstory, whose mass is too concentrating), anti-seismic problem is much outstanding. The characteristics of longitudinal and lateral frame columns are different from general frame columns, due to the high depth-to-width ratio of cross-sections and withstanding large vertical loads. The axial compressive ratio is a very important factor in columns design. Problems are often occurred: cross-section of frame columns depends upon the limit of axial compressive ratio, the constructional reinforcement ratio becomes the ratio of longitudinal reinforcing steel bar of frame columns, such problems are not reasonable. The use of high strength concrete in building constructions has many advantages, such as reducing sectional size of component evidently, alleviating the structure self weight and retrenchment the use of reinforcing steel bar, thus the economic benefit is distinct But the brittleness of high strength concrete causes anxious about its use in the earthquake-resistant structure. The intensity of concrete is higher, and the brittleness of concrete is bigger. Therefore, applying the high strength concrete in the main factory building structure frame columns of large-scale thermal power plants needs to research the valid measure that improves the and seismic deformation capability of high strength concrete frame column. The main contents are followed below:(1) For the aim of knowing the characteristics of main factory building structure frame columns of large-scale thermal power plants, nine high strength concrete frame columns with high axial compression ratio and six slender ordinary strength concrete frame columns with high axial compression ratio were tested under low reversed cyclic horizontal loading for the very first time, and thus the influencing factors of normal section bearing capacity, such as concrete intensity grade, axial compressive ratio, slendemess ratio, the type of stirrups and stirrup ratio, etc, the anti seismic deformation capability of frame columns were acquired. Based on the tests, the advised formula of normal section bearing capacity and inclined section bearing capacity of high strengthen concrete framecolumns are put forward, and the limit of axial compressive ratio and the minimum stirrup ratio in the encrypted region which meet ductility requirement to C60 concrete frame columns are given.(2) Based on the tests and theoretic derivation, skeleton curve of restoring force model of frame column with high axial compression ratio is got. It provides basic data and references to anti-seismic performance and dynamical calculation of high strength concrete monolithic structure.(3) Reinforced concrete frame columns modeled by using three-dimensional solid element to concrete and three-dimensional bar to reinforcing steel bar, and at the same time consideration the adhesive bond between reinforcing steel bar and concrete, the FEM is used. By choosing reasonable element, determining mesh division and load steps, simulation of load-displacement, cracking, yielding and ultimate load, crack development history, and calculating fail crack diagram of reinforcement concrete frame columns under laterally monotonic load are conducted. The analyses are compared with the experimental results. Based on finite element simulating tests of frame columns, load-displacement of frame columns without tests are simulated, and the influencing factors of frame columns are synthetically analyzed.(4) It was figured out that variational history of incremental dissipated hysteretic energy of high strength concrete tentative frame columns under different loading cycle levels; through analyzing all sorts of damage models comparatively, damage model of high strength concrete frame column are put forward, which offers good basement for further damage analysis.更多还原