One of the largest commercial oil companies is developing a new grassroot Petroleum, Oils & Lubricants (POL) terminal at Motihari, Bihar as a first cross border transaction to enable fuel supply to Nepal. This prestigious project aspires to enhance the energy security of the region and substantially reduce the transit cost. Keller was awarded this project on competitive basis to design & execute the specialist ground improvement works to support the foundations of the structures at POL Terminal.
The challenges along the path:
The subsoil up to 30m deep consists of loose to medium dense sand and as the project location falls in highly seismic zone (zone IV) is prone to liquefaction in the event of an earthquake . The major geotechnical challenge was to mitigate the liquefaction potential of the subsoil. In addition to geotechnical challenges Keller also needed to import approximately 90,000cum of s aggregate required to execute the works within stipulated time period of 5months. With the closest material source being 500km from the site we managed the supply chain via a train/rail transport solution. .
Keller conducted extensive geotechnical investigation works by means of Standard penetration tests (SPT), electric Cone Penetration tests with pore pressure measurements (eCPTu), Dilatometer tests (DMT) and Cross hole seismic tests (CHST) to ascertain subsoil properties and to develop the Optimal foundation solution. Keller proposed a ground improvement technique using a combination of Vibro stone columns in the top silty sand where the fines are greater than 15% followed by Vibro compaction in sand layer till the liquefiable depth of 30m. This technique ensured that the required mitigation of liquefaction potential of the subsoil had been economically and technically achieved.
As normal for Keller we maintained a strong, well trained local workforce, with an uncompromising commitment to the HSEQ industry best practice. Our aim is to develop robust and economic geotechnical solutions using the range of techniques we have and to build them safely.