In this study,sprayable strain-hardening fiber-reinforced cementitious composites(FRCC)were applied to strengthen the concrete slabs in a concrete-face rockfill dam(CFRD)for the first time.Experimental,numerical,and a...In this study,sprayable strain-hardening fiber-reinforced cementitious composites(FRCC)were applied to strengthen the concrete slabs in a concrete-face rockfill dam(CFRD)for the first time.Experimental,numerical,and analytical investigations were carried out to understand the flexural properties of FRCC-layered concrete slabs.It was found that the FRCC layer improved the flexural performance of concrete slabs significantly.The cracking and ultimate loads of a concrete slab with an 80 mm FRCC layer were 132%and 69%higher than those of the unstrengthened concrete slab,respectively.At the maximum crack width of 0.2 mm,the deflection of the 80-mm FRCC strengthened concrete slab was 144%higher than that of the unstrengthened concrete slab.In addition,a FE model and a simplified analytical method were developed for the design and analysis of FRCC-layered concrete slabs.Finally,the test result of FRCC leaching solution indicated that the quality of the water surrounding FRCC satisfied the standard for drinking water.The findings of this study indicate that the sprayable strain-hardening FRCC has a good potential for strengthening hydraulic structures such as CFRDs.展开更多
Changes of the material fracture toughness with crack propagation can be described by a crack extension resistance curve,one of the fundamental fracture criteria in crack mechanics.Recently,experimental observation of...Changes of the material fracture toughness with crack propagation can be described by a crack extension resistance curve,one of the fundamental fracture criteria in crack mechanics.Recently,experimental observation of the fracture behavior in concrete was used to develop a new fracture criterion,the crack extension GR resistance curve,to analyze crack propagation during the entire concrete fracture process.The variation of the crack extension resistance is mainly associated with the energy consumption in the fracture process zone ahead of the stress-free crack tip.The crack extension resistance is then a function of the softening curve,which is a basic mechanical property in the fracture process zone.The relationship between the softening curve and the crack extension GR resistance curve is then analyzed based on results of three-point bending beams tests.The results indicate that the characteristic points of the crack extension resistance GR curve is closely related to the characteristic point on used tension softening curve.展开更多
基金This study was financially supported by the National Natural Science Foundation of China(Grant Nos.51978607 and 51878601).
文摘In this study,sprayable strain-hardening fiber-reinforced cementitious composites(FRCC)were applied to strengthen the concrete slabs in a concrete-face rockfill dam(CFRD)for the first time.Experimental,numerical,and analytical investigations were carried out to understand the flexural properties of FRCC-layered concrete slabs.It was found that the FRCC layer improved the flexural performance of concrete slabs significantly.The cracking and ultimate loads of a concrete slab with an 80 mm FRCC layer were 132%and 69%higher than those of the unstrengthened concrete slab,respectively.At the maximum crack width of 0.2 mm,the deflection of the 80-mm FRCC strengthened concrete slab was 144%higher than that of the unstrengthened concrete slab.In addition,a FE model and a simplified analytical method were developed for the design and analysis of FRCC-layered concrete slabs.Finally,the test result of FRCC leaching solution indicated that the quality of the water surrounding FRCC satisfied the standard for drinking water.The findings of this study indicate that the sprayable strain-hardening FRCC has a good potential for strengthening hydraulic structures such as CFRDs.
基金This paper was financially supported by the National Natural Science Foundation of China(Grant No.50438010).
文摘Changes of the material fracture toughness with crack propagation can be described by a crack extension resistance curve,one of the fundamental fracture criteria in crack mechanics.Recently,experimental observation of the fracture behavior in concrete was used to develop a new fracture criterion,the crack extension GR resistance curve,to analyze crack propagation during the entire concrete fracture process.The variation of the crack extension resistance is mainly associated with the energy consumption in the fracture process zone ahead of the stress-free crack tip.The crack extension resistance is then a function of the softening curve,which is a basic mechanical property in the fracture process zone.The relationship between the softening curve and the crack extension GR resistance curve is then analyzed based on results of three-point bending beams tests.The results indicate that the characteristic points of the crack extension resistance GR curve is closely related to the characteristic point on used tension softening curve.
