型钢再生混凝土柱抗震性能及设计计算方法研究

发布时间：2018-06-02 18:50

本文选题：型钢再生混凝土 + 柱　；参考：《西安建筑科技大学》2013年博士论文

【摘要】：型钢再生混凝土组合结构融合了普通型钢混凝土结构承载能力高、抗震性能好的优点和再生混凝土节能环保、可再生利用的显著特点，不但可以提高建筑结构的抗震防灾能力，还符合国家绿色环保和可持续发展的战略，因此具有广阔的发展应用前景。本文通过试验和理论手段，系统研究了型钢再生混凝土柱在低周反复荷载下的力学性能，并提出了相关设计计算理论。根据再生混凝土特点和组合结构要求，设计配制了满足强度要求的再生混凝土材料。在此基础上，本文共设计制作了17个型钢再生混凝土柱试件，设计参数主要包括再生粗骨料取代率、剪跨比、轴压比以及体积配箍率；通过各柱构件的低周反复荷载试验，主要研究了柱构件的破坏过程及破坏形态特征；分析了柱构件在反复荷载作用下的滞回曲线与骨架曲线。在此基础上，对柱构件的抗震承载力、刚度退化、强度衰减、耗能能力、延性以及侧移角等进行了详细研究，并分析了设计参数对型钢再生混凝土柱抗震性能的影响。结合型钢再生混凝土柱构件的特征，并进行一定的简化处理，采用OpenSees软件对型钢再生混凝土柱在低周反复荷载下的滞回性能进行了模拟分析，主要获取了柱构件的滞回曲线及骨架曲线，并将模拟结果与试验结果进行了对比，，验证了有限元分析结果的合理性。在此基础上，分析了再生混凝土强度、型钢强度、配钢率以及箍筋强度对柱构件抗震性能的影响。根据型钢再生混凝土柱滞回性能特点，建立了适合于型钢再生混凝土柱的恢复力模型，该模型采用刚度退化四折线模型，包括骨架曲线模型、刚度退化规律以及滞回规则。利用理论推导和统计回归的方法确定了骨架曲线模型中各个特征点，即开裂点、屈服点、峰值点以及极限点，且相应的给出了加载刚度和卸载刚度，并对计算骨架曲线与实测骨架曲线进行了对比，验证了恢复力模型的合理性。根据延性系数给出了保证型钢再生混凝土柱具有较好抗震性能的试验轴压比限值。依据偏心受压柱大小偏心受压界限破坏理论，推导了发生弯曲破坏的型钢再生混凝土柱轴压比限值的计算方法，并结合试验结果给出了相应的轴压比限值；根据试验轴压比与延性的关系，给出了发生剪切斜压破坏的型钢再生混凝土柱轴压比限值。在分析体积配箍率对柱构件抗震延性有利影响的基础上，给出了不同体积配箍率下型钢再生混凝土柱的轴压比限值。根据试验结果，研究了型钢再生混凝土柱的水平承载力，并分析了再生粗骨料取代率、剪跨比、轴压比以及体积配箍率对柱构件水平承载力的影响。根据型钢、箍筋以及纵筋的应变变化规律，研究了它们各自抵抗水平荷载作用的特点，并分析了型钢再生混凝土柱在水平荷载作用下的受力机理。依据发生不同破坏形态的柱构件受力机理特征，理论推导了柱构件相应的水平承载力计算公式；并提出了型钢再生混凝土柱水平承载力的实用计算公式。根据型钢截面受力特征，给出了型钢与再生混凝土之间粘结应力的计算公式。通过在型钢翼缘外侧粘贴电阻应变片以获得型钢翼缘应变分布情况，分析了型钢翼缘应变的分布规律，并对其进行多次回归分析，获得型钢翼缘在不同荷载数级作用下的各应变点组成的数学描述曲线，并对该曲线进行求导，最后利用所给公式计算得到型钢翼缘外侧的等效粘结力。分析了型钢再生混凝土柱粘结应力分析规律及特征；根据型钢再生混凝土柱在反复荷载作用下的粘结退化机理及特征，并结合试验结果，给出了柱构件的粘结应力退化计算表达式。结合试验研究，分析了型钢再生混凝土柱在低周反复荷载作用下的地震损伤特点，并对柱构件的地震损伤进行了量化处理。在分析归纳现有地震损伤模型的基础上，结合型钢再生混凝土柱的特点，建立了基于变形和累积滞回耗能非线性组合的型钢再生混凝土柱地震损伤模型。对计算损伤指数和试验损伤指数进行了比较，验证了柱构件地震损伤模型的合理性；分析了再生粗骨料取代率、剪跨比、轴压比以及体积配箍率对型钢再生混凝土柱地震损伤性能的影响。
[Abstract]:The reinforced concrete composite structure combines the advantages of high bearing capacity , good aseismatic performance and the remarkable characteristics of recycled concrete energy saving , environment protection and sustainable development . It can not only improve the seismic disaster prevention capacity of the building structure , but also meet the national green environmental protection and sustainable development strategy . Therefore , this paper studies the mechanical properties of the SRC column under repeated loading at low cycle and puts forward the relevant design calculation theory .

According to the characteristics of recycled concrete and the requirements of combined structure , the recycled concrete material meeting the strength requirement has been designed and prepared . Based on this , 17 sections of recycled concrete column specimens have been designed and fabricated . The design parameters mainly include the substitution rate of recycled coarse aggregate , the shear span ratio , the axial compression ratio and the volume matching ratio .
Through the low - cycle repeated load test of each column component , the damage course of the column component and the characteristics of failure morphology are studied .
In this paper , the hysteretic curves and skeleton curves of column members under repeated loading are analyzed . On the basis of this , the seismic bearing capacity , stiffness degradation , strength attenuation , energy dissipation capacity , ductility and lateral displacement angle of column members are studied in detail . The influence of design parameters on the seismic behavior of SRC columns is analyzed .

Combined with the characteristics of SRC column components , the hysteretic behavior of SRC columns under low - cycle repeated loading is simulated and analyzed by OpenSees software . The results of simulation are compared with the experimental results , and the rationality of the results of finite element analysis is verified . On the basis of this , the influence of strength of recycled concrete , steel strength , steel distribution rate and hoop strength on seismic behavior of column members is analyzed .

Based on the characteristics of hysteretic behavior of SRC column , a model of restoring force suitable for SRC column is established . The model adopts four - fold model of stiffness degradation , including skeleton curve model , stiffness degradation law and hysteresis rule . The method of theoretical derivation and statistical regression is used to determine each feature point in skeleton curve model , namely , crack point , yield point , peak point and limit point , and the load stiffness and unload stiffness are given , and the calculation skeleton curve is compared with the measured skeleton curve , and the rationality of the restoring force model is verified .

According to the ductility coefficient , the limit value of the axial compression ratio of the reinforced concrete column with better seismic resistance is given . According to the eccentric compression limit damage theory of the eccentric compression column , the calculation method of the axial compression ratio limit of the SRC column with bending failure is deduced , and the corresponding limit value of the axial compression ratio is given in combination with the test results .
Based on the relationship between axial compression ratio and ductility , the limit of axial compression ratio of SRC column with shear slope failure has been given . On the basis of analyzing the influence of volume matching ratio on seismic ductility of column members , the axial compression ratio limits of SRC columns with different volume ratios are given .

According to the experimental results , the horizontal bearing capacity of SRC column is studied , and the influence of the substitution rate of recycled coarse aggregate , the ratio of shear - span ratio , axial compression ratio and the volume matching ratio on the horizontal bearing capacity of column members is analyzed . According to the rule of strain law of section steel , stirrup and longitudinal bar , the characteristics of their respective resistance to horizontal load are studied , and the stress mechanism of SRC column under horizontal load is analyzed .
A practical formula for calculating the horizontal bearing capacity of SRC column is presented .

According to the characteristic of section stress of section steel section , the formula for calculating the bond stress between section steel and recycled concrete is given . The distribution rule of strain distribution of section steel flange is analyzed by sticking resistance strain gauge on the outer side of section steel flange . The mathematical description curve of section steel flange ' s strain distribution under different loads is analyzed . Finally , the equivalent cohesive force on the outer side of section steel flange is obtained by using the given formula . The law and characteristics of bond stress analysis of SRC column are analyzed .
According to the mechanism and characteristics of bond degradation under repeated loading of SRC column , the calculation expression of bond stress degradation of column members is given .

Based on the analysis of the existing seismic damage model , the seismic damage model of the SRC column based on the combination of deformation and accumulated hysteretic energy consumption is established . The calculation damage index and the test damage index are compared , and the rationality of the seismic damage model of the column member is verified .
The influence of the substitution rate of recycled coarse aggregate , the ratio of shear span ratio , axial compression ratio and the volume matching ratio on the seismic damage performance of SRC column was analyzed .
【学位授予单位】：西安建筑科技大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU398.9;TU352.11

【参考文献】