In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive ...In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive damage evolution,hydrostatic pressure,strain rate,and the Lode angle effect.The proposed model was embedded in LS-DYNA software and then comprehensive tests were carried on a hexahedral brick element formulation under uniaxial,biaxial,and triaxial stress states to verify its rationality through comparisons with results determined by the HJC and Karagozian&Case(K&C)models.Finally,the proposed model was used to simulate the damage caused to UHTCC targets subjected to blast by embedded explosive and projectile penetration,and predictions were compared with corresponding experimental results.The results of the numerical simulations showed that our proposed model was more accurate than the HJC model in predicting the size of the crater,penetration depth,and the distribution of cracks inside the target following the blast or high-speed impact loading.展开更多
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
基金Project supported by the National Natural Science Foundation of China(Nos.51678522 , 51878601)。
文摘In this study,an explicit dynamic constitutive model was established for ultra high toughness cementitious composites(UHTCCs).The model,based on the Holmquist–Johnson–Cook(HJC)model,includes tensile and compressive damage evolution,hydrostatic pressure,strain rate,and the Lode angle effect.The proposed model was embedded in LS-DYNA software and then comprehensive tests were carried on a hexahedral brick element formulation under uniaxial,biaxial,and triaxial stress states to verify its rationality through comparisons with results determined by the HJC and Karagozian&Case(K&C)models.Finally,the proposed model was used to simulate the damage caused to UHTCC targets subjected to blast by embedded explosive and projectile penetration,and predictions were compared with corresponding experimental results.The results of the numerical simulations showed that our proposed model was more accurate than the HJC model in predicting the size of the crater,penetration depth,and the distribution of cracks inside the target following the blast or high-speed impact loading.
基金supported by the National Natural Science Foundation of China(No.51478423)the Research Foundation of the Department of Education of Zhejiang Province,China(No.Y201226058)the Research Fund for the Doctoral Program of Higher Education of China(No.20130101120071)
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.
