OPTIMAL DESIGN OF STRENGTHENING WIND EXPOSURE RESISTANCE OF VERTICAL WHIPSTITCH MENTAL ROOFING BOARD

The domestic public buildings with vertical whipstitch metal roofing board designed before 2012 have suffered wind damage due to the obvious low negative wind pressure by the design according to the 2006 load code. Strengthening its wind exposure resistance is very important for the safe use of this kind of existing public buildings. The combination of vertical whipstitch mental roofing board system has now widely been used in the practice of roofing systems for public buildings. This article expounds the wind exposure principle of the vertical whipstitch metal roofing board system and makes a preliminary analysis on the wind exposure resistance of the key components of the vertical whipstitch metal roofing board system under complex stresses as well as extreme storm conditions, based on the actual needs of the reinforcement design case after the destruction of the existing vertical whipstitch metal roofing board system in Terminal T2 of Changbei Airport. Through the analysis of the force transfer path and failure characteristics of the vertical whipstitch metal roofing board system, the idea of strengthening design optimization has been formed for what the existing vertical whipstitch metal roofing board system should ensure the key area, take into account the general area, and should be determined by the physical anti-wind exposure contrast test, and the method has been put forward for the evaluation and concrete optimization through the physical anti-wind exposure test. Through a series of comparative tests on the load-bearing performance of wind exposure, an effective method is also put forward for adding different spacing fixtures on the supports of the existing vertical whipstitch metal roofing board in the general area and the reinforced area, respectively. Particularly, it is proposed to further improve the anti-hatching ability at the head of existing vertical whipstitch metal roofing board for avoiding the ‘tearing-paper-damage chain effect’. It can not only provide the scientific basis for the reinforcement design of this kind of existing roof, but also provide a valuable reference for the design of new metal roofing construction projects similar as large stadiums.