新型混合装配式混凝土剪力墙抗震性能研究

In order to break through key problems of precast shear wall, such as earlier cracking, poor energy dissipation and premature crushing of concrete, new hybrid precast concrete shear wall (NHPW), based on the combination technique of partially deboned of grouting-anchoring overlapping reinforcement, unbounded posttensioned connection and connected closed hoop, is put forward in this project. The seismic performance of NHPW is studied through two levels of section and component. The main content of this project is as following. 1) Introducing key parameters brought about by core technology, the stress calculation and parameter analysis on horizontal connection section under the combined compression and bending moment are carried out to grasp the section mechanism and establish its ductile failure mode. 2) With introducing nominal tension strain in tensile region of section and adopting the fiber model, the connection section is equivalently serialized. Then, parameterized model for the section is determined considering the parameter analysis results. 3) Based on the section's parameterized model, the theoretical analysis model on seismic mechanism for component is established which is in the form of multi-liner model and can reflect the mechanic behavior of component under horizontal load. Then parameter analysis is carried out using the component's theoretical analysis model. 4) Based on the results of numerical modeling and model test, the component's theoretical analysis model will be verified and revised. At last the preliminary and applicative seismic design procedure for NHPW component will be proposed by inverting analysis on the component's theoretical analysis model. The research achievements of this project are expected to resolve basic problems for NHPW's application in high-rise buildings in moderate and high intensity seismic fortification area and provide reference and theoretical basis for the in-depth application of NHPW in the seismic engineering.

为解决装配式剪力墙开裂较早、耗能能力较低、水平拼缝混凝土过早压溃等难题，集成局部无粘结浆锚钢筋间接搭接连接技术、无粘结预应力压接技术及扣接封闭箍筋技术，开发新型混合装配式混凝土剪力墙，并从截面与构件层次研究其抗震性能。 主要研究内容包括：1）通过水平拼缝截面在压-弯组合作用下的受力计算与参数分析，掌握其受力机理，提出其延性破坏机制；2）引入截面受拉区名义拉应变及其分布，基于纤维模型，将拼缝截面进行等效连续化，并建立拼缝参数化模型；3）基于拼缝参数化模型，建立反映构件在水平荷载作用下受力全过程的多线性模型，将其作为构件抗震机制的理论分析模型，通过参数分析掌握各参数对构件抗震性能的影响规律；4）基于数值模拟及模型试验结果，验证并修正构件理论分析模型，通过反演分析提出适用的构件抗震设计程序。 研究成果可望解决装配式混凝土剪力墙应用于中、高烈度抗震设防区高层建筑的基本问题，为深入工程应用提供依据。

由于建筑行业转型升级迫切需求，建筑工业化逐渐成为行业关注与研究热点，装配式混凝土结构则是建筑工业化发展的重要方向。我国中、高层建筑，尤其是建设需求量极大的住宅建筑，大量采用剪力墙结构，因此，装配式混凝土剪力墙结构成为我国当前发展重点，并形成了多种代表性的装配式混凝土剪力墙结构技术体系。.基于国外混合装配系统，为适应我国目前主推的“等同现浇”理念，提出了新型混合装配式混凝土剪力墙（New Hybrid Precast Shear Wall，以下简称NHPW），通过集成后张无粘结预应力技术、浆锚钢筋局部无粘结技术以及扣接封闭箍筋技术，以期解决既有的装配式混凝土剪力墙与现浇剪力墙相比存在的开裂较早、混凝土破坏相对集中等问题。为验证并探讨NHPW的抗震性能，项目针对性地开展了系列模型试验、有限元模拟及理论分析工作。项目的主要工作及成果如下：.（1）对8片足尺NHPW模型和1片现浇对比模型开展了低周反复荷载加载试验，模型设计中考虑了预应力筋面积、预应力筋初始预应力、浆锚钢筋无粘结长度以及轴压比参数的变化，系统分析了模型的破坏形态、承载力、刚度、延性、耗能、残余变形等抗震性能指标，探讨了各设计参数对NHPW模型抗震性能的影响规律。.（2）基于试验结果，采用有限元分析软件ABAQUS建立其有限元模型，并将分析结果与试验结果对比以验证有限元模型对试验结果的再现性。并基于有限元模型，通过参数分析，将试验未考虑的参数取值进行补充分析，进一步验证或拓展试验得到的各设计参数对NHPW抗震性能的影响规律。.（3）基于既有受弯构件计算理论，探讨NHPW模型在开裂、屈服、极限等关键阶段或受力特征点的荷载与刚度计算方法。将初步计算结果与试验结果对比，根据参数影响规律的结论，采用数值拟合法，将对各强度、刚度理论解影响敏感的参数考虑进理论计算公式中，最终得出适用于NHPW、且与试验数据吻合良好的强度与刚度修正计算方法。.通过上述试验研究与理论分析工作，对NHPW的抗震性能有了较为深入的了解，为NHPW后续进一步研究及工程应用奠定了数据与理论基础。