Wind-Resistant Analysis for Large-span Single-layer Reticulated Shells

Abstract

Single-Layer Reticulated Shells are a kind of space-latticed system with the features of bar system structures and thin shells. For their structural design, wind loading is very important since they are sensitive to external loading distribution and stability is an important, even dominant problem. Generally, nonlinear dynamic time-history analysis is an effective way to give a convinced result, but the time-consuming computation and the cost for obtaining the time-series data of wind pressure from wind tunnel tests should be considered at first. At present, usually equivalent static methods based on the quasi-steady assumption are used in the structural wind-resistant design in practice. However, the estimated equivalent static wind loading distribution may not reflect the actual effects of fluctuating wind loading on stability of shells, which may lead to an unsafely higher limit load-carrying capacity. In this paper, wind pressure distribution on a spherical shell model was measured simultaneously in wind tunnel first. A framework for nonlinear dynamic time-history analysis of wind-induced vibration for single-layer reticulated shells was introduced. Based on the measured wind pressure data, nonlinear time-history analysis, including dynamic instability analysis of a single-layer reticulated spherical shell was conducted as an example. Then, several equivalent static wind loading estimation methods were discussed and compared, including a new simple method presented by the authors from the stability point of view. Finally, with comparison analyses, it was proved that the presented method can be used to improve the efficiency of the effective static loading distribution estimation, as well as to give a conservative estimation of the effects of wind loading on single-layer reticulated shells, especially in stability analysis.