型钢混凝土空间边节点受力性能与抗剪强度研究

Mechanism Performance and Shear Strength Study of SRC Spatial Exterior Joints

基于已有试验建立型钢混凝土(SRC)梁柱平面节点有限元模型,在验证数值模拟准确性的基础上,建立SRC空间边节点有限元模型,分析空间加载角度和轴压比对该节点受力性能的影响。通过细化加载角度找出空间边节点柱端峰值荷载与加载角度关系的数学模型。将空间边节点分解为主轴方向的十字形和T形构件进行受力分析,提出空间边节点核心区受剪承载力计算公式,并利用数值模拟结果验证其准确性。研究结果表明:SRC空间边节点在两主轴方向水平荷载作用下的柱端极限承载力不相等,且正向加载下柱端极限承载力高于负向加载;柱端极限承载力与加载角度关系曲线为不对称的椭圆形,可利用椭圆形参数公式分段表示;节点在斜向荷载作用下,核心区抗剪承载力与柱端极限荷载成正比,椭圆形参数公式同样适用于核心区抗剪承载力;SRC空间边节点核心区在斜向加载下的抗剪承载力公式计算值与模拟值吻合良好。

A finite element model is presented to analyze the mechanical behavior of steel reinforced concrete (SRC) beam-column plane joints. On the basis of verifying the accuracy of numerical simulation, finite element models of SRC spatial exterior joints were established, and the influence of space loading angle and axial compression ratio on the mechanism performance of the joint was analyzed. The mathematical model of the relationship between the peak load and the load angle was found by refining the loading angle. The spatial exterior joint was decomposed into the cross-shaped and T shaped members in the main axis direction for force analysis, the calculation formula of the spatial joint core area shear capacity is proposed and its accuracy is verified with the numerical simulation results. The research results show that the peak load of the column end loaded along the two main axis directions is not equal, and the ultimate bearing capacity of the column end under positive loading is higher than that under negative loading;the relationship between the ultimate bearing capacity and the loading angle is asymmetric ellipse, and it can be expressed in sections by the ellipse parameter formula;the shear capacity of the joint core area under oblique loading is proportional to the ultimate load of the column end, and the formula is also applicable to the core area shear resistance bearing capacity;the calculated value of core area shear bearing capacity formula under oblique loading is in good agreement with the simulated value.