Experimental study of precast segmental columns with unbonded tendons under cyclic loading

Abstract

Precast segmental column has attracted a lot of interests over the past decade. It has become more and more popular in construction industry to achieve fast construction, improve construction quality and reduce environmental impact. Many factors including the energy dissipation bar, number of segments, prestressing force and shear keys could affect the performance of segmental column, but each of previous studies normally focused on investigating one or two of these factors. Since different previous studies used different materials, different structural dimensions, different axial loads and different testing methods, it is difficult to have comprehensive comparisons of the influences of these parameters on the performances of segmental columns. Moreover, limited studies indicated that shear keys had insignificant influences on performances of segmental columns subjected to cyclic loadings, while other studies revealed shear keys contribute to resisting impact loads but could lead to more severe damage due to stress concentration. In this study, cyclic tests were carried out to systematically assess the performance of segmental columns. Special attentions were paid on the influences of shear keys on column responses. Five scaled segmental columns with different designs were tested to study their damage mode, hysteretic behaviour, residual drift and energy dissipation capacity. One monolithic column was also tested as a reference. Test results showed that comparing with the monolithic column, the segmental columns exhibited better ductility and smaller residual drift, indicating better seismic performance, but segmental columns had less loading capacity and absorbed less energy. The influences of different designs including energy dissipation bar between adjacent segments, number of segments, prestressing force level in the tendon and concrete shear key on the seismic performance of segmental column were investigated and discussed.

Comparison study of time-varying seismic fragility of precast segmental and cast-in-place bridge columns in high-speed railway bridges

“…PSBC has a different structural composition than CPBC, which includes joints, energy dissipation (ED) bars and unbonded prestressed tendon (PT) strands (Li et al, 2017). Its working performance is very different from CPBC.…”

“…Due to the discontinuity between segments, the seismic performance of PSBC is recognized to be weaker than that of CPBC (Jia et al, 2020). Scholars at home and abroad have performed many studies on the working performance of PSBCs, such as cyclic load tests (Li et al, 2017), shaking table tests (Li et al, 2019), and impact tests (Do et al, 2019) and so on. The PSBC is more likely to show quasi -elastic behavior in medium and small earthquakes (Tong et al, 2021).…”

The mechanical performance of concrete shear key for prefabricated structures

“…Precast segmented concrete structures have gained much popularity in construction industry. Many studies have been conducted on precast segmented concrete structures to widen its applications (Kim et al, 2010; Li et al, 2018; Ou et al, 2007; Zhang et al, 2016a,b; Zhang et al, 2018a). Concrete shear key is one of the most common connections for precast concrete structure.…”

The response of precast concrete segmental columns subjected to near base impact

“…To widen the application of segmental column and apt to high seismic areas, many researches have been performed over the past decades on cyclic loading capacities of segmental columns, focusing on the evaluation and improvement of their seismic performance (Dawood et al, 2011; ElGawady and Dawood, 2012; Kim et al, 2010; Li et al, 2018; Ou et al, 2007; Shim et al, 2008; Zhang et al, 2018b). Different laboratory tests and numerical simulations have been performed.…”