Lightweight Concrete: Mechanical Properties

Abstract

Much of the fundamental basis for the current lightweight concrete provisions in the AASHTO LRFD Bridge Design Specifications is based on research of lightweight concrete (LWC) from the 1960s. The LWC that was part of this research used traditional mixes of coarse aggregate, fine aggregate, portland cement, and water. Broad-based advancement in concrete technology over the past 50 years has given rise to significant advancements in concrete mechanical and durability performance. This document describes the mechanical property tests that were conducted as part of an overall FHWA research project on LWC. The FHWA test results are included in a sizable LWC database of mechanical properties from tests available in the literature. An analysis of the LWC database was used to develop potential revisions to provisions related to LWC within Chapter 5 of the AASHTO LRFD Specifications. A framework for addressing LWC in the specifications is proposed wherein the definition of LWC, the mechanical properties of LWC, and a modification factor relevant to LWC structural performance is discussed.\n