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为研究铝合金网壳箱形、工字形截面杆件盘式连接节点(又称TEMCOR节点、板式节点)的受力性能,对南京牛首山佛顶宫工程典型铝合金盘式节点足尺试件进行了静力加载试验,采用通用有限元程序ABAQUS对加载过程进行全过程数值模拟。在进行静力加载试验时,铝合金杆件端部采用铰接,在节点盘中心区域设置加载板进行竖向加载。研究结果表明:在节点盘中心竖向荷载作用下试件发生脆性破坏。对向两杆为箱形截面(试件JD1)时,箱形截面杆件下翼缘发生断裂,上下节点盘屈曲,且与断面相邻的螺栓被拉断;对向杆件为工字形截面(试件JD2)时,下节点盘发生块状撕裂,破坏时铝合金型材及螺栓均无屈曲和破坏。在极限荷载作用下,试件JD1杆件腹板及节点盘仍处于弹性工作状态,箱形截面中性轴位于截面中间;试件JD2铝合金型材处于弹性工作状态,工字形截面中性轴位于截面强轴以下1/6腹板高度处,下节点盘在α=60°及α=180°方向应力较大,接近屈服强度。试件JD1的极限荷载和初始刚度均约为试件JD2的1.5倍。根据对称性建立的节点试件数值模型分析所得的局部应力、荷载-位移曲线及弯矩-转角曲线与试验结果吻合较好,可以用于此类节点的数值模拟。
In order to study the mechanical properties of box-shaped and I-shaped section bar disk-type joints (also known as TEMCOR joints and plate joints) of aluminum alloy grid shells, the full-scale specimens of typical aluminum alloy disc joints The static loading test was carried out, and the whole process of loading process was simulated by the general finite element program ABAQUS. During the static loading test, the ends of the aluminum alloy rod are hinged, and the loading plate is arranged in the central area of the node disk for vertical loading. The results show that the specimen brittle failure under the vertical load of the center of the disk. When the two bars are box-shaped (test piece JD1), the lower flange of the box-section bar fractures, the upper and lower node discs buckle, and the bolt adjacent to the section is pulled off; the opposite bar is an I-shaped section (Specimen JD2), the underlying node plate occurred massive tearing, failure of aluminum alloy profiles and bolts without buckling and damage. Under the action of ultimate load, the webs and node plates of JD1 rod are still in elastic working state, the neutral axis of box section is located in the middle of the section; the specimen JD2 aluminum alloy is in elastic working state, the I-shaped neutral axis is in Below the strong axis of the cross section, the stress at the web height of 1 / 6th under the α = 60 ° and α = 180 ° joints is larger and the yield strength is close to the yield strength. The ultimate load and initial stiffness of the specimen JD1 are both about 1.5 times that of the specimen JD2. The local stress, load-displacement curve and bending moment-rotation curve obtained from the numerical model of the joint specimen established by the symmetry agree well with the experimental results and can be used for numerical simulation of such nodes.