Strength failure of spatial reticulated structures under multi-support excitation

Abstract

Under strong earthquakes, long-span spatial latticed structures may collapse due to dynamic instability or strength failure. The elasto-plastic dynamic behaviors of three spatial latticed structures, including two double-layer cylindrical shells and one spherical shell constructed for the 2008 Olympic Games in Beijing, were quantitatively examined under multi-support excitation (MSE) and uniform support excitation (USE). In the numerical analyses, several important parameters were investigated such as the peak acceleration and displacement responses at key joints, the number and distribution of plastic members, and the deformation of the shell at the moment of collapse. Analysis results reveal the features and the failure mechanism of the spatial latticed structures under MSE and USE. In both scenarios, the double-layer reticulated shell collapses in the "overfl ow" mode, and the collapse is governed by the number of invalid plastic members rather than the total number of plastic members, beginning with damage to some of the local regions near the supports. By comparing the numbers and distributions of the plastic members under MSE to those under USE, it was observed that the plastic members spread more suffi ciently and the internal forces are more uniform under MSE, especially in cases of lower apparent velocities in soils. Due to the effects of pseudo-static displacement, the stresses in the members near the supports under MSE are higher than those under USE.

Study of Seismic Resistance of Kiewit-8 Dome Considering Key Structural Design Parameters

“…According to the LPGA changing to the cubic curve model is the best model among several different models of curve estimation with a very small variance 0.1122. Referring to Equation (11), the relationship between the lower bound collapse loads and rise to span ratios could be given by: where RSR ∈ [0.1, 0.5] is the rise to span ratio.…”

“…Referring to Equation (11), the relationship between lower bound collapse loads and rise to span ratios could be given by:…”

“…Single-layer domes are adopted worldwidely as long-span roofs in recent decades [1][2][3] because of their advantages, such as their good aesthetic appearance, large space coverage capability and sound structural performance. Current research work is mainly focused on the structural response [4][5][6][7][8][9][10], collapse [11][12][13] of the steel structure under different loads through experiment and numerical simulation analysis [14][15][16][17][18], considering stability and buckling [19][20][21][22]. Only few reports have investigated the structural dynamic failure modes [17,19,23,24] and the seismic failure loads when the single-layer reticulated shells are subject to earthquakes.…”

Comparison of seismic responses of a reticulated dome under stochastic uniform and spatially correlated and coherent multiple-support excitation for a scenario seismic event

“…12 The coherence models are often considered in the estimation of the seismic responses of structures or structural systems with multiple supports. [13][14][15][16][17][18][19] In these studies, simulated ground motion records are used since the available historical records are insufficient for selecting the records matching inter-support distances of a structure, desired seismic magnitude (or intensity) and site to seismic source distance. For example, ground motion records are simulated for a target power spectral density (PSD) function and a predefined coherence function for analysing the response of the transmission line towers in Yang et al, 20 for multi-span bridges in Soyluk and Sicacik, 16 and for spatial reticulated structures in previous studies.…”

“…For example, ground motion records are simulated for a target power spectral density (PSD) function and a predefined coherence function for analysing the response of the transmission line towers in Yang et al, 20 for multi-span bridges in Soyluk and Sicacik, 16 and for spatial reticulated structures in previous studies. 17,18,21,22 The flexibility of substructures can also influence the responses of latticed shells. [23][24][25] The records simulated and used in these studies cannot reproduce the observed spatial correlation of ground motion measures or the Fourier amplitude spectrum (FAS), and are not directly linked to scenario events that are often characterized by the combination of the earthquake magnitude and site to seismic source distance.…”