Effect of the measurement technique on the amount of maximum pore pressures measured inside concrete subjected to high temperatures

Title: Effect of the measurement technique on the amount of maximum pore pressures measured inside concrete subjected to high temperatures
Author(s): R.B. Mugume, T. Horiguchi
Paper category : conference
Book title: 2nd International RILEM Workshop on Concrete Spalling due to Fire Exposure
Editor(s): E.A.B. Koenders and F. Dehn
ISBN: 978-2-35158-118-6
e-ISBN: 978-2-35158-119-3
Publisher: RILEM Publications SARL
Publication year: 2011
Pages: 87 - 94
Total Pages: 8
Nb references: 10
Language: English

Abstract: Precise pore pressure measurement is one of the most important factors in understanding the mechanisms of spalling of concrete due to fire exposure. Different measurement techniques have been used by different researchers to measure pore pressure inside heated concrete. It was observed that some researchers measure rather low maximum pore pressures and still experienced explosive while other researchers measured high maximum pressures.

In this experimental study, the effect of the measurement technique on the amount of maximum pore pressures measured inside High Strength Concrete was examined. Three different gauges have been used with the first gauge made of only a tube, the second made of a tube which has a metal cup brazed on its top and the third made of a tube which has a metal cup brazed on its top and a sintered metal encapsulated in the metal cup. In order to study the effect of a medium used in the pipe to transform pressure to the outside of the specimen on the amount of pore pressures measured, silicon oil and air were used as the two media in the pipe.

Pressure gauge comprising of a sintered metal measured a higher amount of pore pressure compared to other two gauges examined which clearly showed that a sintered metal has a significant effect on the amount of pore pressures measured. Higher pore pressures were measured for specimens with gauges filled with silicon oil compared to specimens with empty gauges for all different types of pressure gauges used. Also pressure measurements for gauges without silicon oil resulted in unstable pore pressure results.
Therefore the pressure measurement technique which utilizes a sintered metal and silicon oil is the most effective technique for pore pressure measurement.

Online publication: 2012-01-17
Publication type : full_text
Public price (Euros): 0.00