【摘要】 常规交叉网格结构侧向刚度高、材料利用效率高，但是在地震中的延性和能量耗散能力较低，摩擦耗能节点可以改善此类问题。广州三一集团华南总部、树根互联总部双子塔项目采用混凝土核心筒和周边六边形钢管混凝土网格双重体系，六边形网格在水平段中央布置了摩擦耗能节点。当节点竖向剪力超过摩擦耗能器预设的摩擦阈值时，节点左右两侧将相对滑动，从而耗散地震能量并防止相邻构件中的力继续增加。为了研究摩擦节点在高层交叉网格结构中的消能减震效果，进行了摩擦材料性能试验，研究了摩擦材料的特性，验证了所采用的摩擦装置的出力稳定性，并确定了设计采用的摩擦系数。对预设的摩擦阈值进行了研究，确保节点在小震下不发生滑动，而在约80%中震时发生滑动。采用有限元分析方法考察了重力、温度、地震等工况下带来的节点附加轴力对摩擦力的影响，并在设计中进行考虑。采用非线性时程分析研究了结构在罕遇地震下的性能，结果表明摩擦节点在大震中按预期发生滑动并耗散能量，摩擦节点消耗的总能量接近结构非线性耗能的50%。施工图设计阶段减少了摩擦节点数量，但是分析表明依然可以在地震中有效耗能。更多还原

【Abstract】 Conventional cross-grid structures exhibit high lateral stiffness and use material efficiently,but have low ductility and energy dissipation capability during seismic events. This situation can be improved with friction energy dissipating nodes. The structural system for SANY iRootech Twin Towers in Guangzhou,utilizes a concrete core and a peripheral hexagonal steel tube concrete grid. Friction energy dissipation nodes were centrally arranged within the horizontal sections of the hexagonal grid. When vertical shear forces at the nodes exceed the preset threshold of the friction energy dissipator,relative sliding occurs between the left and right sides of the node. Thus,seismic energy was dissipated,preventing further force increse in adjacent members.To investigate the energy dissipation and seismic mitigation performance of friction nodes in high-rise cross-grid structures,friction material tests were conducted. The material characteristics were examined,the force stability of the friction devices was validated,and the design friction coefficient was determined. The preset friction threshold was studied to ensure nodes remain non-sliding during frequently occurred earthquakes while initiating sliding at approximately 80% of design basis earthquake intensities. Finite element analysis was used to examine the influence of additional axial forces on friction caused by gravity,temperature,and seismic loading,incorporating these effects into the design. Nonlinear time-history analysis was performed to elevate the structural performance in rarely occurred earthquakes.The results show that friction nodes slip in rarely occurred earthquakes and dissipate energy as expected,accounting for about 50% of the total seismic energy dissipated by structural nonlinearity. In the construction drawing design stage,the number of friction nodes was reduced,but can still increase the energy dissipation in earthquakes.更多还原