Structural performance evaluation of a precast prefabricated bridge column under vehicle impact loading

International Journal of Impact Engineering

2016

107

A B S T R A C TAlthough precast concrete segmental columns have been more and more widely used in constructions, there is a lack of study on its behaviour under dynamic loading especially impact loading. In this paper, the fundamental behaviour of precast segmental columns under impact loading is investigated through laboratory tests. Scaled precast segmental columns with unbonded posttensioning tendon were constructed and tested using pendulum impact system. Two segmental columns of the same height, but with different numbers of precast segments were designed and tested. A conventional monolithic reinforced concrete (RC) column was also casted and tested as a reference column to compare the performance with segmental columns under impact loading. The impact load time history and column displacement time histories at column top, mid-height and column base were recorded. The deformation-to-failure processes of the columns were monitored by a high-speed camera, and used to investigate the response of different columns under impact loads. The test results showed the segmental column is more flexible than monolithic column, which leads to lower peak impact force, but longer duration compared to those on the monolithic RC column. It was also found that compared with monolithic columns, segmental columns show better performance against impact load with better self-centring capability, similar energy dissipation capability and less residual displacement and concrete damage.

Section: Impact Load Time Historymentioning

confidence: 99%

“…The only article available in the literature is a recent numerical study on segmental columns under vehicle impact [12]. A precast segmental column 2.3 m in diameter and 16.25 m high together with a detailed truck was modelled in the analysis.…”

Section: Introductionmentioning

confidence: 99%

Experimental investigation of the response of precast segmental columns subjected to impact loading

Zhang

International Journal of Impact Engineering

2016

107

“…It is, therefore, necessary and important to properly understand the response of segmental column under impact loading. Recently, Chung et al (2014) reported their numerical study on bridge pier made of segmental concrete elements with post-tensioning tendon under vehicle impact. A relatively large segmental pier and a small truck striking at low velocity were modelled and studied.…”

Section: Introductionmentioning

confidence: 99%

The effect of concrete shear key on the performance of segmental columns subjected to impact loading

Zhang

Advances in Structural Engineering

2016

Conventional precast segmental columns with seismic resistance design consist of only flat concrete segments with prestress tendon. This is because friction between adjacent segments is sufficient to resist the lateral forces from earthquake-induced actions. However, the friction between segments is not necessarily sufficient to resist lateral impact loads such as vehicle impact the column might experience during its service life. This article investigates the effectiveness of using concrete shear key in segments of precast segmental column in resisting the lateral impact loading. The precast reinforced concrete segments were designed with concrete shear keys to improve the column shear resistance capacity and minimize the relative displacement between adjacent segments. Two groups of segmental columns with and without shear key were designed and tested using a pendulum impact system. The effectiveness of shear key in resisting lateral impact loads was analysed by comparing the performance of the two groups of segmental columns. The testing results revealed that by introducing concrete shear key to segmental column, the relative displacement between adjacent segments could be effectively reduced. However, the large concrete shear key increased stress concentration in the concrete segments. Relatively, more severe damages to concrete segments were found on the columns with shear key. Further improvements on shear key designs should be made for better performance of segmental columns against impact loading.

“…However, amplified moment would be experienced by the column because of P-delta effect. Study on response of segmental columns against impact loading is still limited (Chung et al, 2014;Zhang et al, 2016aZhang et al, , 2016b. Since the loading amplitude, duration, and action location on the column from impact load are all very different from that of seismic loading, the response and failure mode of a segmental column under impact loading is likely to be different from that under seismic loading.…”

Section: Introductionmentioning

confidence: 99%

Multi-hazard resistance capacity of precast segmental columns under impact and cyclic loading

Xi-hong

International Journal of Protective Structures

2018

Using precast segmental concrete columns in structures improves the construction efficiency and site safety, leads to better construction quality, and reduces the construction cost, site disruption and environmental impact. The performance of segmental columns to resist earthquake and impact loads is not well studied yet. As a structure might be subjected to such loads during its service life, understanding its resistance capacities is essential for structural safety. This article reports the findings of our recent studies on the response of precast segmental columns with unbonded prestress tendons. Pendulum impact test and uniaxial cyclic test were conducted on quarter-scale segmental columns. The seismic performance and impact-resistant capacity were evaluated experimentally and compared with a reference conventional monolithic column. Test results showed that under cyclic loading, segmental columns exhibited better deformation ability and smaller residual drift; under impact loading, segmental columns also showed better self-centring capacity and less residual displacement. By introducing concrete shear key, the shear resistance at segmental joint could be improved; however, shear key would also result in more concrete segment damage owing to stress concentration.