Project Description

This project involved construction of a foundation for the fuel oil tanks (2 tanks 45 m diameter, 19 m high) which were part of the construction of a 2 * 341 MW Gas-Fuel Fired Power Plant.

The soil is made of a first very bad layer of clay in the upper 7 m followed by a very good sand layer 3 m thick and by sand and clay layers to a depth of 30 m. The initial design proposed the construction of a raft foundation resting on piles driven to 35 m through all soft soil layers.

DGI-Menard proposed an alternative solution which was more economical and less time consuming. This was particularly attractive since the foundations tasks where on the critical paths of the civil engineering tasks in the overall project schedule.

The tank was built on a simple concrete slab of 30 cm resting on a 40 cm layer of well-compacted sand supported by the upper soft soil layer reinforced by means of a network of Controlled Modulus Column (CMC) soil inclusions 8 meters deep, 400 mm in diameter installed on a 1.35 meter square grid down to the first good sand strata. CMC is the name of the DGI-Menard patented Controlled Modulus Column foundation system.

The DGI-Menard alternative resulted in substantial savings due to the reduced length of the CMC compared to the piles and to the simplification of the structure (no pile caps and only a concrete slab).