Researching Explosive Spalling

This article examines the issue of explosive spalling of concrete tunnel linings during a fire, and the use of polypropylene fibers to combat the problem. Recent tunnel fires have shown that explosive spalling of concrete has caused significant and costly damage to as well as risk to human life. In 2003 the NewCon Project was launched to examine the influence of polypropylene fibers on explosive spalling. The author reviews small- and large-scale tests that have been conducted, including TNO tests, CETu tests, and toxicity analysis. The article includes a number of tables and graphic representations.