Test methods for characterizing concrete properties at elevated temperature

Abstract

Summary Fire resistance of structural members is dependent on the thermal and mechanical properties of constituent materials and these properties vary as a function of temperature. Currently, there are limited standardized test procedures for evaluating thermal and mechanical properties of construction materials at elevated temperatures. This paper provides a review and assessment of test methods and procedures for evaluating high temperature thermal and mechanical properties of concrete. The drawbacks and variations in currently available test procedures and methods in standards are discussed. Recommendations on the most suitable methods and procedures for measuring thermal and mechanical properties at elevated temperature is presented. In addition, applicability of the proposed high temperature test methods and procedures is illustrated through a case study on conventional concrete specimens. Further, the need for developing standards by organizations such as American Society for Testing and Materials (ASTM), with standardized specifications and test procedures for measuring high temperature properties of construction materials, is laid out.

Study on the Thermodynamic Properties of Concrete Surface during Microwave Deicing of Airport Pavement

“…Hot blowing is a kind of deicing operation using a jet deicing vehicle which is equipped with an aeroengine as the power unit. In practical operation, the high-temperature and high-speed air flow can easily damage the concrete structure and affect the thermal and mechanical properties of concrete under elevated temperatures [6][7][8][9].…”

Advancements in evaluating the fire resistance of structures

“…After stringent peer review, 12 of the 17 oral presentations are presented here as full papers. The papers accepted for this issue were on the following topics[5][6][7][8][9][10][11][12][13][14][15][16] :Due to modern developments in the construction materials industry, to ensure design safety, we are being challenged with requiring significant understanding of new materials and their performance in fire. Since 1918, the standard fire time-temperature curve has been utilized to assess the fire resistance of building materials.…”

“…After stringent peer review, 12 of the 17 oral presentations are presented here as full papers. The papers accepted for this issue were on the following topics: Comparative Energy Analysis from Fire Resistance Tests on Combustible vs Non‐combustible Slabs The Discrepancies in Energy Balance in Furnace Testing, a Bug or a Feature? A New Test Methodology for Studying the Response of Walls to Real Fire Environments Simulating Real Compartment Fire Conditions in a Furnace Rectification of “Restrained vs. Unrestrained” Fire Resistance of Cold‐formed Steel Framed Shear Walls under various Fire Scenarios Development and Application of a Simulation Approach for Fire and Structure Interaction of Concrete Members subject to Spalling Test Methods for Characterizing Concrete Properties at Elevated Temperatures Evaluation of Standard and Real Fire Exposures on Thermal Response of Rail Car Floor Assembly Best Practices for Modeling Structural Boundary Conditions Due To a Localized Fire Flame Extension and the Near Field under the Ceiling for Travelling Fires Inside Very Large Compartments An Extended Travelling Fire Method (ETFM) Framework for Performance‐based Structural Design …”

Improving the Fire Resistance of Concrete Masonry Walls

“…They remain close to constant for the duration of the test. After the test was done and the walls had cooled completely the deflections decreased, but did In non-loadbearing tests, the specimens are built to fit tightly into a semi-rigid rectangular frame and the resistance provided by the frame makes it unlikely for any cracks to open up [5]. Also, because the frame restrains the walls "the main body of the wall curves in a spherical shape with cracks across the four corners".…”

“…There has been limited testing conducted on full scale masonry walls. A large portion of the research into concrete mix designs is conducted using small concrete cubes which are not always applicable to masonry blocks or masonry walls, and do not account for the effects of the mortar [3] [4] [5]. When research is conducted to investigate the effects of fire on masonry, the tests are normally conducted on small scale masonry walls (usually masonry prisms a few blocks high) [6] [7].…”