Stiffening-ribbed-hollow-pipe cast-in place reinforced concrete girderless floor is a new-style hollow girderless floor system. Model experimental researches of simply-supported floor and four-corners bearing floor ha...Stiffening-ribbed-hollow-pipe cast-in place reinforced concrete girderless floor is a new-style hollow girderless floor system. Model experimental researches of simply-supported floor and four-corners bearing floor have been done on this new kind of floor system in this paper. The experiment results show that the floor system has good mechanical property such as high bearing capacity, big rigidity and good tensility. A theoretical method is presented in this paper that the stiffening-ribbed-hollow-pipe girderless floor can be analyzed by being converted equivalently to orthotropic solid slab. It is indicated that the method is correct and reasonable according to the contrast between theoretical calculated results and experimental measured results. The theoretical results coincide with the measured results well.展开更多
Three-dimensional(3D)-printed scaffolds are widely used in tissue engineering to help regenerate critical-sized bone defects.However,conventional scaffolds possess relatively simple porous structures that limit the de...Three-dimensional(3D)-printed scaffolds are widely used in tissue engineering to help regenerate critical-sized bone defects.However,conventional scaffolds possess relatively simple porous structures that limit the delivery of oxygen and nutrients to cells,leading to insufficient bone regeneration.Accordingly,in the present study,perfusable and permeable polycaprolactone scaffolds with highly interconnected hollow-pipe structures that mimic natural micro-vascular networks are prepared by an indirect onepot 3D-printing method.In vitro experiments demonstrate that hollow-pipe-structured(HPS)scaffolds promote cell attachment,proliferation,osteogenesis and angiogenesis compared to the normal non-hollow-pipe-structured scaffolds.Furthermore,in vivo studies reveal that HPS scaffolds enhance bone regeneration and vascularization in rabbit bone defects,as observed at 8 and 12weeks,respectively.Thus,the fabricated HPS scaffolds are promising candidates for the repair of critical-sized bone defects.展开更多
文摘Stiffening-ribbed-hollow-pipe cast-in place reinforced concrete girderless floor is a new-style hollow girderless floor system. Model experimental researches of simply-supported floor and four-corners bearing floor have been done on this new kind of floor system in this paper. The experiment results show that the floor system has good mechanical property such as high bearing capacity, big rigidity and good tensility. A theoretical method is presented in this paper that the stiffening-ribbed-hollow-pipe girderless floor can be analyzed by being converted equivalently to orthotropic solid slab. It is indicated that the method is correct and reasonable according to the contrast between theoretical calculated results and experimental measured results. The theoretical results coincide with the measured results well.
基金supported by the National Natural Science Foundation of China(82072400,82102211,52173117)the Natural Science Foundation of Jiangsu Province(BK20200001)+4 种基金the Natural Science Foundation of Shanghai(20ZR1402500)the Belt&Road Young Scientist Exchanges Project of Science and Technology Commission Foundation of Shanghai(20520741000)Ningbo 2025 Science and Technology Major Project(2019B10068)the Science and Technology Commission of Shanghai Municipality(20DZ2254900,20DZ2270800)the Fundamental Research Funds for the Central Universities,DHU Distinguished Young Professor Program(LZA2019001).
文摘Three-dimensional(3D)-printed scaffolds are widely used in tissue engineering to help regenerate critical-sized bone defects.However,conventional scaffolds possess relatively simple porous structures that limit the delivery of oxygen and nutrients to cells,leading to insufficient bone regeneration.Accordingly,in the present study,perfusable and permeable polycaprolactone scaffolds with highly interconnected hollow-pipe structures that mimic natural micro-vascular networks are prepared by an indirect onepot 3D-printing method.In vitro experiments demonstrate that hollow-pipe-structured(HPS)scaffolds promote cell attachment,proliferation,osteogenesis and angiogenesis compared to the normal non-hollow-pipe-structured scaffolds.Furthermore,in vivo studies reveal that HPS scaffolds enhance bone regeneration and vascularization in rabbit bone defects,as observed at 8 and 12weeks,respectively.Thus,the fabricated HPS scaffolds are promising candidates for the repair of critical-sized bone defects.
