Uniaxial compression tests were conducted to characterize the main compressive performance of ultra high toughness cementitious composite （UHTCC） in terms of strength and toughness and to obtain its stress-strain re...Uniaxial compression tests were conducted to characterize the main compressive performance of ultra high toughness cementitious composite （UHTCC） in terms of strength and toughness and to obtain its stress-strain relationships. The compressive strength investigated ranges from 30 MPa to 60 MPa. Complete stress-strain curves were directly obtained, and the strength indexes, including uniaxial compressive strength, compressive strain at peak stress, elastic modulus and Poisson＇s ratio, were calculated. The comparisons between UHTCC and matrix were also carried out to understand the fiber effect on the compressive strength indexes. Three dimensionless toughness indexes were calculated, which either represent its relative improvement in energy absorption capacity because of fiber addition or provide an indication of its behavior relative to a rigid-plastic material. Moreover, two new toughness indexes, which were named as post-crack deformation energy and equivalent compressive strength, were proposed and calculated with the aim at linking up the compressive toughness of UHTCC with the existing design concept of concrete. The failure mode was also given. The study production provides material characteristics for the practical engineering application of UHTCC.展开更多
After 20 years of systematic studies,15 subfamilies,38 genus and 104 species of braconid wasp in Hunan province are recorded.According to the studies on both male and femal genitalia of Aridelus hunanensis You,Xio...After 20 years of systematic studies,15 subfamilies,38 genus and 104 species of braconid wasp in Hunan province are recorded.According to the studies on both male and femal genitalia of Aridelus hunanensis You,Xiong et Zhou and Aridelus rutilipes Papp,and on both male genitalia of Streblocera flava You et Xiong and Streblocera okadai Watanabe,it is pointed in this paper that Aridelus hunanensis You,Xiong et Zhou and Streblocera flava You et Xiong are still considered valid independent species.This disagrees with Chen X.’s and C.van Achterberg’s (1997) opinion that Aridelus hunanensis You,Xiong et Zhou is a junior synonym of Aridelus rutilipes Papp,and Streblocera flava You et Xiong is the same species of Streblocera okadai Watanabe. Key words:Braconid wasp;taxonomy;fauna;展开更多
基金Funded by the Key Program of National Natural Science Foundation of China( No.50438010)the Research & Application of Key Technology for the South-North Water Transfer Project Construction in China ( JGZXJJ2006-13)
文摘Uniaxial compression tests were conducted to characterize the main compressive performance of ultra high toughness cementitious composite （UHTCC） in terms of strength and toughness and to obtain its stress-strain relationships. The compressive strength investigated ranges from 30 MPa to 60 MPa. Complete stress-strain curves were directly obtained, and the strength indexes, including uniaxial compressive strength, compressive strain at peak stress, elastic modulus and Poisson＇s ratio, were calculated. The comparisons between UHTCC and matrix were also carried out to understand the fiber effect on the compressive strength indexes. Three dimensionless toughness indexes were calculated, which either represent its relative improvement in energy absorption capacity because of fiber addition or provide an indication of its behavior relative to a rigid-plastic material. Moreover, two new toughness indexes, which were named as post-crack deformation energy and equivalent compressive strength, were proposed and calculated with the aim at linking up the compressive toughness of UHTCC with the existing design concept of concrete. The failure mode was also given. The study production provides material characteristics for the practical engineering application of UHTCC.
基金Project(2022JJ30583) supported by the Natural Science Foundation of Hunan Province,ChinaProject(21B0315) supported by the Natural Science Research Project of Hunan Education Department,ChinaProject(18ZDXK04) supported by the Civil Engineering Key Discipline Innovation Project of Changsha University of Science and Technology,China。
文摘After 20 years of systematic studies,15 subfamilies,38 genus and 104 species of braconid wasp in Hunan province are recorded.According to the studies on both male and femal genitalia of Aridelus hunanensis You,Xiong et Zhou and Aridelus rutilipes Papp,and on both male genitalia of Streblocera flava You et Xiong and Streblocera okadai Watanabe,it is pointed in this paper that Aridelus hunanensis You,Xiong et Zhou and Streblocera flava You et Xiong are still considered valid independent species.This disagrees with Chen X.’s and C.van Achterberg’s (1997) opinion that Aridelus hunanensis You,Xiong et Zhou is a junior synonym of Aridelus rutilipes Papp,and Streblocera flava You et Xiong is the same species of Streblocera okadai Watanabe. Key words:Braconid wasp;taxonomy;fauna;
