Key Achievements

• Efficiently installed and monitored vibro stone columns for large diameter steel tanks foundation in a variable ground condition where soil ranged from very soft to dense.

• Keller’s design and build capability helped in addressing critical geotechnical concern of differential and total settlement.

The Project

JBF Petrochemical industries Ltd proposed to construct new paraxylene terephthalic acid plant of 1.25 MMTPA capacity in Mangalore, India. The plant mainly comprised of structures like storage tanks, process plants, substations and other ancillary buildings. Keller was commissioned by the main contractor to design and execute ground improvement works for handling three paraxylene tanks and two fire water storage tanks of diameters 35 meters and 64 meters.

The Challenge

The subsoil condition at proposed site was soft to firm sandy with varying thickness layer followed by very dense silty sand or weathered rock. The challenge associated with the underlain soil was to enhance the bearing capacity of the variable soil profile whilst limiting the total and differential settlement of tank pad foundation. Along with ground improvement works, tank pad civil works were to be envisaged for three paraxylene tanks and two fire water storage, which was critical for project success.

The Solution

Keller designed a solution where ground improvement work was accomplished using dry bottom feed vibro stone columns to enhance the bearing capacity of the soil whilst limiting the total and differential settlement. Tank pad work included laying of stone blanket, HDPE membrane, sand pad and bitumen works.