Foshan Steel Design Knowledge: Vertical regularity Tall buildings which seismic design points?
Vertical rules of Tall Buildings Seismic Design Essentials What?
Design elements:
Overrun 1) facade revenue caused by the layer structure should ensure that the shear capacity of not less than 80% on an adjacent floor, and structural changes in effect controlled within a reasonable range. Incorporated into the site of the vertical component and the floor should be strengthened. Facade revenue if the formation of migraine pain, the bottom of the structure changes due to greater internal forces, therefore, constructed around the bottom reinforcement member should be strengthened. Where possible, the facade should be used repeatedly stepped adduction. Structural analysis should focus on whether the mutation displacement inspection structure, structure stiffness along the height of the spread or without mutations alter the effect of whether the structure is controlled within a reasonable range.
2) One-piece construction joints and surrounding should be used to calculate the elastic plate, connected to the main body should adopt the weak link (eg: hinged), it should be possible to reduce the weight and priority should be constructed of steel. Seismic level connected with the main body and the adjacent structural members should raise the level of adoption.
3) open a large hole in the facade focus on strengthening the hole corners and edges around the hole to prevent cracking in the hole angle when a small earthquake.
4) For the cantilevered structure, the design should consider the vertical seismic action. The quality of the upper structure cantilevered structure is large, too large to change the moment of inertia, if there is quality migraine pain, it will have a serious effect change, the design should be avoided.
5) with a conversion layer structure, the upper and lower body as much as possible is arranged through a series of vertical structure, and down through the core tube should try to strengthen the lower body structure stiffness, weakened upper body structure stiffness, take measures to control the conversion layer up and down the equivalent stiffness ratio, increasing the proportion of the pillars bear the seismic shear box, improving ductility and seismic capacity of the box support layer. Can reduce the stiffness of the upper layers (such as partial use of short pier shear wall), lower than the equivalent stiffness and down conversion layer. Conversion layer, the greater the impact of higher modes, conversion layer between the upper and lower internal forces of mutation and drift more obvious, therefore, should be strictly controlled to set the height conversion layer.
6) the large multi-tower chassis, the design should consider increasing the carrying capacity of the chassis to prevent construction in the bottom of the first yield. Connecting the tower podium roof stiffness should be increased to ensure that the bottom of the skirt can bring together the upper part of the tower vibration. But the bottom will result in the strengthening of the weak layer shift that increases the displacement of the upper structure, which should be a good grasp of the bearing capacity of the strengthened measures to improve the chassis. To strengthen the weak parts of the tower were designed, the layer should be whole column stirrup high encryption, stirrups diameter increased, the level of shear reinforcement is also appropriate to strengthen.