Mechanical behaviors of UHTCC after freezing and thawing were investigated,and compared with those of steel fiber reinforced concrete(SFRC),air-entrained concrete(AEC) and ordinary concrete(OC).Four point bendin...Mechanical behaviors of UHTCC after freezing and thawing were investigated,and compared with those of steel fiber reinforced concrete(SFRC),air-entrained concrete(AEC) and ordinary concrete(OC).Four point bending tests had been applied after different freezing-thawing cycles(0,50,100,150,200 and 300 cycles,respectively).The results showed that residual flexural strength of UHTCC after 300 freezing-thawing cycles was 10.62 MPa(70% of no freezing thawing ones),while 1.58 MPa(17% of no freezing thawing ones) for SFRC.Flexural toughness of UHTCC decreased by 17%,while 70% for SFRC comparatively.It has been demonstrated experimentally that UHTCC without any air-entraining agent could resist freezing-thawing and retain its high toughness characteristic in cold environment.Consequently,UHTCC could be put into practice for new-built or retrofit of infrastructures in cold regions.展开更多
基金Funded by the Key Program of National Natural Science Foundation of China (No.50438010)
文摘Mechanical behaviors of UHTCC after freezing and thawing were investigated,and compared with those of steel fiber reinforced concrete(SFRC),air-entrained concrete(AEC) and ordinary concrete(OC).Four point bending tests had been applied after different freezing-thawing cycles(0,50,100,150,200 and 300 cycles,respectively).The results showed that residual flexural strength of UHTCC after 300 freezing-thawing cycles was 10.62 MPa(70% of no freezing thawing ones),while 1.58 MPa(17% of no freezing thawing ones) for SFRC.Flexural toughness of UHTCC decreased by 17%,while 70% for SFRC comparatively.It has been demonstrated experimentally that UHTCC without any air-entraining agent could resist freezing-thawing and retain its high toughness characteristic in cold environment.Consequently,UHTCC could be put into practice for new-built or retrofit of infrastructures in cold regions.