Reactive Powder Concrete

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Submitted By shivaramvarma
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Concrete Repair, Rehabilitation and Retrofitting II – Alexander et al (eds)
© 2009 Taylor & Francis Group, London, ISBN 978-0-415-46850-3

Performance of Reactive Powder Concrete (RPC) with different curing conditions and its retrofitting effects on concrete member
T.P. Chang, B.T. Chen, J.J. Wang & C.S. Wu
Department of Construction Engineering, National Taiwan University of Science and Technology,
Taipei, Taiwan, ROC

ABSTRACT: The material performance of Reactive Powder Concrete (RPC) with two different curing conditions, water-curing of 25ºC and steam-curing of 85ºC and 95% relative humidity, were studied experimentally. The reinforcing effects of the RPC with two wrapping thicknesses of 10 and 15 mm, respectively, on the surface of cylindrical concrete specimen were evaluated. Major experimental results show both the engineering properties and indices of durability of RPC with steam-curing at four different ages have substantially increased except for the supersonic pulse velocity and dynamic moduli of elasticity and shear. The ratio of increase of compressive strength of cylindrical specimens retrofitted with 10 and 15 mm of wrapping RPC are in the range of 9.5 to 38.0%.
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INTRODUCTION

Reactive powder concrete (RPC), a cement-based composite material well known for the ultra-highstrength, high-durability and low-porosity, made its international debut in 1994 (Richard, 1994). The advance mechanical and physical properties of RPC are obtained by optimizing packing density of concrete mixture with precise gradation of all mix particles, and by using highly refined silica fume to improve the microstructure of hydrated cement pastes through the pozzolanic reaction. To produce a very high compressive strength of RPC, applications of pressure before and during setting and heat-treating after setting are normally required. Compressive…...

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