摘要
为研究型钢超高强混凝土(SRHC)框架中节点的抗剪承载力,对12榀SRHC框架中节点试件进行低周反复加载试验。试验结果及相关文献分析表明轴压力系数、配箍率及型钢是影响节点抗剪承载力的主要因素。建立考虑以上因素的SRHC框架中节点抗剪承载力计算模型,分别考虑型钢腹板、核心区与非核心区混凝土斜压柱以及桁架机制对节点抗剪的贡献。选取包括文中试验在内的3组型钢混凝土框架中节点试验,分别采用文中抗剪模型和我国相关规范中的计算公式预测其抗剪承载力。对比研究表明:规程JGJ 138—2001能合理地预测普通强度混凝土的SRC柱-RC梁框架节点的抗剪承载力,但对于高强或超高强混凝土的SRC柱-SRC梁框架节点的计算偏于不安全;规程YB 9082—2006计算结果过于保守;文中模型的抗剪承载力计算公式能合理地预测不同混凝土强度的型钢混凝土框架中节点的抗剪承载力,适用于SRHC框架中节点的抗剪设计。
Twelve interior steel reinforced high strength concrete （SRHC） beam-column joints were tested under lateral cyclic force and constant axial load. Based on experimental results and relevant literatures, it is found that axial pressure coefficient, volumetric ratio of stirrups and structural steel are the main factors affecting the shear strength of joints. A model was developed to determine the shear strength of interior SRHC beam-column joints considering the main factors, with the contributions of steel web, inner and outer concrete diagonal struts and truss mechanism to the shear strength of joints considered. Three groups of tests, including the one designed in this study and the other two, were selected for the comparison study. The shear bearing capacities of these joints were evaluated by the model and code formulas, respectively. Comparison study shows that Code JGJ 138-2001 may reasonably predict the shear strength of SRC column-RC beam joints made by normal strength concrete, but may overestimate the strength of SRC column-SRC beam joints made by high strength concrete. While Code YB 9082-2006 underestimates the shear strength of joints made by concrete with various strength. Comparatively, the proposed model may predict the shear strength of joints made by concrete with various strength reasonably, and hence it is suitable for the shear design of interior SRHC beam-column joints.
出处
《土木工程学报》
EI
CSCD
北大核心
2013年第10期1-8,共8页
China Civil Engineering Journal
基金
国家自然科学基金(50878037
51078059
51178078)
关键词
型钢超高强混凝土
中节点
抗剪承载力
抗剪机制
steel reinforced high strength concrete
interior joints
shear strength
shear-resistance mechanism
