Proceedings of DFI-India 2019: 9th Conference on Deep Foundation Technologies for Infrastructure Development in India, (DFI)
Pile Foundation for Cable Support Structure in Brownfield Site with Underground Obstructions - A Case Study
Manos De, Vijay Bhatt and Shuvranshu Rout
The execution of projects in brownfield site conditions with restricted space throws up additional challenges especially in foundation construction and design. Engineering design for foundations of structures in such projects involves not only correctly applying the principles of science but also meeting unknown challenges posed by variations in assumed sub-surface conditions. This paper talks about a case study in an existing plant being retrofitted with new equipment where the pipe and cable supporting structures connecting the various units had to be located, designed and executed considering existing structure in the vicinity. However, even after careful planning and ground survey to locate the facilities at the most convenient location to meet design and construction requirements, there were unknown surprises thrown up during construction from unknown subsurface utilities. The location of the tower structure foundation was found to have numerous underground utility services like pipes and cables in live condition that could not be disturbed. There was no place to install the piles required for the foundation at the design location; also, it was not possible to reroute the new pipes or find alternate location for the structure. Solution to this seeming impasse was arrived at by innovative design of the foundation and superstructure that avoided the interference to piling operation posed by existing live service lines and without altering the location of the tower structure to preclude modification in the already fabricated pipe and cable gallery structure. The structure and foundation were redesigned to avoid the critical zone of interference to piling operation. This solution could be executed successfully through innovative concepts, careful planning, collection of survey data and continuous interaction with site.
|article #3310; publication #1059 (India2019)|