Enhancement of seismic damage endurance of large-span lattice shells with replaceable fuse-type components

Abstract

Most large-span public buildings in highly seismic regions are supposed to play the role of post-earthquake emergency relief centers or shelters, in addition to their original functions. As one type of commonly-used structural systems in those buildings, large-span lattice shells are required to retain some post-earthquake seismic damage endurance. To reach this goal, a new replaceable bi-functional stiffness-damping component with the use of low-yield point (LYP) steel element is developed. To determine the placement of fuse-type components in lattice shells rationally, the plastic limit theory of equivalent continuum shell is employed for the classification of primary-secondary structural systems. The proper proportion of fuse-type components and their connection constraints with primary structural system is further clarified by an accompanied parametric study. The assessment on seismic damage endurance and reserve strength of lattice shells with fuse-type components is finalized with the residual seismic capacity ratio and seismic damage model proposed previously. The effectiveness of the proposed seismic damage endurance enhancement strategy for lattice shells with the use of replaceable fuse-type components is fully demonstrated on a case study on a 121.5m-span single-layer Kiewitt lattice shell. In this study, the effects of layout of fuse-type components, V/H ratio and spectral characteristics of ground motion, LYP yield strength, normalized length of ‘fuse’ elements are identified from the aspects of ultimate earthquake resistance, the maximum nodal displacement, seismic damage development, residual seismic capacity and reserve strength. • A seismic damage endurance enhancement strategy for lattice shells is proposed. • A new replaceable fuse-type component using low-yield point steel is developed. • Fuse-type components are replaced using the equivalent continuum shell theory. • Four performance regions are divided by relation between RSC and reserve strength.