Investigate the applicability of different structural configurations for bridge/ via duct pier in local expressway

Abstract

Piles with tie beams are mostly used as a practice in the expressway bridges in Sri Lanka. Even though it seems to be cost effective, the reliability of the substructure in some soil conditions, might be quite low when compared to other structural configurations like piles with pile cap. A study on this matter will be helpful to identify a suitable structural configuration for substructure in terms of structural, geotechnical, and economical aspects. For this study, a bridge located in the Central Expressway project in Sri Lanka was considered. Pile with tie beam configuration and 4 other possible alternative configurations for the selected bridge were identified. All five structural configurations were analysed under 3 different soil profiles which are taken from some of the locations in the Central Expressway in Sri Lanka. Some empirical equations were used to assess geotechnical aspects in terms of load carrying capacity and the expected settlement. Meanwhile, Midas Civil 2020 software was used for the structural analysis, while Euro code was referred for the structural design. Based on the results presented in this paper, it is evident that, pile cap with friction piles can be used conveniently, if proper controlled driving of piles is done.