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An experimental investigation was conducted to identify the characteristics of crack growth in high performance concrete (HPC) subjected to fire, including two parts of work, i.e. crack growth resistance determinations and cracking observations, using concrete of three strength grades 40 MPa, 70 MPa, and 110 MPa. The crack growth resistance curves (R-curves ) of HPC subjected to high temperatures were determined using notched three-point bend beam specimens of 100 mm×100 mm×300mm. The R-curve (crack growth resistance curve) flattening shows that the crack growth resistance has been significantly reduced by elevated temperature. Concrete with a higher strength grade has a steeper R-curve, with a higher fracture toughness but a shorter critical crack growth. The shorter critical crack growth means that concrete of a higher strength grade has a more brittle behavior. The concrete cracking observations reveal that the consequences of rapid heating are quite different from those of slow heating. For slow he
An experimental investigation was conducted to identify the characteristics of crack growth in high performance concrete (HPC) subjected to fire, including two parts of work, ie crack growth resistance determinations and cracking observations, using concrete of three strength grades 40 MPa, 70 MPa, and 110 MPa. The crack growth resistance curves (R-curves) of HPC subjected to high temperatures were determined using notched three-point bend beam specimens of 100 mm × 100 mm × 300 mm. shows that the crack growth resistance has been significantly reduced by elevated temperature. Concrete with a higher strength grade has a steeper R-curve, with a higher fracture toughness but a shorter critical crack growth. strength grade has a more brittle behavior. The concrete cracking observations reveal the the following of rapid heating are quite different from those of slow h For slow he