The Woodside Liquid Natural Gas extension IV project was an extension of the production facilities of the North West Shelf Project on the Burrup Peninsula in Northern Western Australia.

The temperature requirements of the specification involve the temperature differential between the interior and any outside face to be not greater than 17°C per 1 MPa of indirect tensile strength for a block type foundation with a smallest dimension up to 1 metre and 13°C per 1 MPa when the least dimension exceeds 1 metre.

The client required calculations to show the theoretical temperature differential for thick slabs of 900 mm thickness or greater and walls of 600 mm thickness or greater. Dr James Aldred working with Taywood Engineering conducted the calculations and thermocouple installation to confirm compliance for numerous elements in the on-plot and off-plot extension.

Below is an example of the measured peak and surface temperatures as well as the allowable differential. The concept of the allowable temperature differential increasing dependent on the tensile strength of the concrete helps account for the increased strain capacity of the concrete due to its in-situ maturity.