MAIN CONTENTS OF THE STANDARD FOR WIND LOADS ON ROOF STRUCTURES

This paper comprehensively introduces the main contents of the Standard for Wind Loads on Roof Structures. Regarding the wind-induced response analyses and wind-resisting design for main load-resisting structures of roofs, the nominal values of wind loads on the main structures are expressed by the sum of mean wind pressures and equivalent static wind pressures. The equivalent static wind pressures correspond to extreme responses induced by fluctuating wind loads, which can be obtained by the proposed method for single or multiple targets. On these bases, the design figures and tables of shape factors for the mean wind pressures and equivalent pressure factors for fluctuating wind responses considering multiple targets are presented for different types of roof structures. These include plane truss structures, beam string structures, grid truss structures, spherical/cylindrical shell structures, saddle structures and overhanging structures. The extreme wind pressure coefficients are estimated based on specified methods, which are applicable to different cases of short/long wind pressure samples, to consequently determine the nominal values of wind loads on cladding and components. Furthermore, the design figures and tables of corresponding extreme wind pressure coefficients are proposed for mono-slope, gable, hip roofs of low-rise buildings; roofs of middle-/high-rise buildings; open roofs and overhanging canopies. Generally, in the current Standard for Wind Loads on Roof Structures, the Chinese wind-resisting design specifications for roof structures have been improved by introducing the concepts of equivalent pressure factors for the wind-induced fluctuating responses of main load-resisting structures and the extreme wind pressure coefficients of cladding and components.