Proceedings of DFI-India 2018: 8th Conference on Deep Foundation Technologies for Infrastructure Development in India, (DFI)
Foundation Anchoring for Stability in Brownfield Site
Manos De, Soumik Chakraborty, Anup Kumar Mandal, Shuvranshu Rout and Pradip Kumar Nandi
Executing projects in brown field site conditions throws up many challenges requiring innovative approach for feasible solutions. In the present case foundation for a heavily loaded storage silo support structure was required to be designed at a site with numerous closely located existing services. The required foundation plan area was under adjacent existing road which was planned to be temporarily diverted. However at time of execution temporary shutdown of part of the road was not allowed by plant operation. Also during excavation presence of an underground water pipe was revealed and this pipe could not be diverted or temporarily rerouted since it was vital for operation of existing plant. The foundation layout had to be modified to avoid disruption to these facilities but because of the critical loading conditions from superstructure, reduction in foundation area was resulting in loss of required stability of the foundation. Since the governing condition for inadequate stability was found to be overturning effect from moment under seismic conditions, alternative design for the foundation within available footprint space was carried out by providing rock anchors. The anchors were provided along the periphery of the foundation to maximize the stabilizing effect. This paper presents the case study on the evaluation of the layout and construction restrictions on the designed foundation, planning and design of the alternative solution to suit site conditions and provide the required factor of safety for stability of the foundation, design of the anchors and installation procedure, load testing of anchors and finally constructing the foundation within the limitations. The implemented solution achieved the desired safety of the foundation while maintaining all facilities in the operating plant unhindered.
|article #3173; publication #1050 (India2018)|