How Is an LNG Terminal Structurally Engineered in Louisiana?

The delta soil profile drives every foundation decision at a Louisiana LNG terminal. Soft clays with low shear strength and high compressibility extend dozens of feet down, the water table sits near grade, and the whole coast is subsiding - so shallow foundations are out of the question for heavy structures. The geotechnical investigation maps each stratum with borings, cone penetration tests, and laboratory consolidation testing, giving the structural engineer the skin friction and end-bearing values needed to size piles and predict settlement over the facility's multi-decade life. Pile installation gets intense quality control because the tanks cannot tolerate surprises. Test piles with dynamic or static load testing confirm capacity before production piling, driving records are reviewed for every pile, and integrity testing checks for defects. Where schedule allows, the site may be surcharged - loaded with fill to squeeze water from the clays before construction - so that most consolidation settlement happens before the tanks arrive rather than under them. Settlement monuments and piezometers then monitor the ground through construction and into operation.

Full-containment tanks earn their name: the outer concrete tank is a complete secondary container, not just a dike. Its prestressed walls and roof are designed for the hydrostatic and thermal loads of a full inner-tank release, plus the environmental loads - hurricane wind on a 200-foot-diameter cylinder is enormous, and seismic design must account for the sloshing mass of thousands of tons of liquid. The annular insulation, typically expanded perlite, keeps heat leak low enough that boil-off gas stays within the handling system's capacity. The marine facilities face the open waterway's forces. Trestles and loading platforms stand on piles designed for vessel berthing impact, mooring line pulls, hurricane surge, and ship-collision considerations at the berth. Fenders absorb berthing energy, and the loading arms that transfer LNG to carriers need precise alignment - so the dolphin structures are designed for tight deflection limits. Every in-water structure also goes through the Corps of Engineers and Coast Guard reviews that govern work in navigable waterways.