The Behavior of High Performance Structural Lightweight Concrete at Elevated Temperatures

Results from a three year experimental study of the behavior of a high-strength (60 MPa) lightweight aggregate (LWA) concrete at elevated temperatures, including simulated hydrocarbon fire exposure, are described. Mechanical properties as a function of temperature (to 800 C) are also presented, as well as a summary of behavior in fire, and a comparison with normal density high performance and ordinary LWA concretes under similar conditions is made. In addition, a simple and practical method for limiting the propensity of very low permeability, high performance concretes to explosively spall at elevated temperatures is demonstrated. Finally, the first application of this concrete in a major floating oil platform, the quarter-million ton Heidrun TLP, is highlighted. High performance LWA concrete is shown to posses all the best physical, mechanical, and durability characteristics of normal density high performance concretes while still retaining the superior high temperature and fire resistance properties of ordinary lightweight concretes -- an ideal combination of properties for construction of offshore platforms.