To solve the deficiency of steel anchor blot in corrosion resistance and flaw of GFRP anchor bolt in fracture resistance, our research group develops a new composite anchor bolt made of steel strands wrapped up with c...To solve the deficiency of steel anchor blot in corrosion resistance and flaw of GFRP anchor bolt in fracture resistance, our research group develops a new composite anchor bolt made of steel strands wrapped up with compound fiber resin. To improve the cohesion performance of the composite anchor bolt, pull-out tests of different composite anchor bolts with different groove intervals and depths were made and analyzed. The results show that the pulling resistance of the composite anchor bolt increases with the increase of groove interval and depth, but groove interval and depth have optimal value. Based on elastic mechanics, the cohesion between anchor bolts and anchor bodies and its distribution characteristics caused by axial tension are analyzed and cohesion formula is obtained. By contrast, the experimental result is consistent with the theoretical analysis. Therefore, the surficial change of anchor colts could influence the performance of the composite anchor bolt. The cohesion force and anchorage performance can be improved by changing the surface of anchor bolts. Research results show that the new composite anchor bolt is high-performance material in the civil engineering.展开更多
Rapid and efficient tendon fixation to a bone following trauma or in response to degenerative processes can be facilitated using a tendon anchoring device.Osteomimetic biomaterials,and in particular,bio-resorbable pol...Rapid and efficient tendon fixation to a bone following trauma or in response to degenerative processes can be facilitated using a tendon anchoring device.Osteomimetic biomaterials,and in particular,bio-resorbable polymer composites designed to match the mineral phase content of native bone,have been shown to exhibit osteoinductive and osteoconductive properties in vivo and have been used in bone fixation for the past 2 decades.In this study,a resorbable,bioactive,and mechanically robust citrate-based composite formulated from poly(octamethylene citrate)(POC)and hydroxyapatite(HA)(POC-HA)was investigated as a potential tendon-fixation biomaterial.In vitro analysis with human Mesenchymal Stem Cells(hMSCs)indicated that POC-HA composite materials supported cell adhesion,growth,and proliferation and increased calcium deposition,alkaline phosphatase production,the expression of osteogenic specific genes,and activation of canonical pathways leading to osteoinduction and osteoconduction.Further,in vivo evaluation of a POC-HA tendon fixation device in a sheep metaphyseal model indicates the regenerative and remodeling potential of this citrate-based composite material.Together,this study presents a comprehensive in vitro and in vivo analysis of the functional response to a citrate-derived composite tendon anchor and indicates that citrate-based HA composites offer improved mechanical and osteogenic properties relative to commonly used resorbable tendon anchor devices formulated from poly(L-co-D,l-lactic acid)and tricalcium phosphate PLDLA-TCP.展开更多
文摘To solve the deficiency of steel anchor blot in corrosion resistance and flaw of GFRP anchor bolt in fracture resistance, our research group develops a new composite anchor bolt made of steel strands wrapped up with compound fiber resin. To improve the cohesion performance of the composite anchor bolt, pull-out tests of different composite anchor bolts with different groove intervals and depths were made and analyzed. The results show that the pulling resistance of the composite anchor bolt increases with the increase of groove interval and depth, but groove interval and depth have optimal value. Based on elastic mechanics, the cohesion between anchor bolts and anchor bodies and its distribution characteristics caused by axial tension are analyzed and cohesion formula is obtained. By contrast, the experimental result is consistent with the theoretical analysis. Therefore, the surficial change of anchor colts could influence the performance of the composite anchor bolt. The cohesion force and anchorage performance can be improved by changing the surface of anchor bolts. Research results show that the new composite anchor bolt is high-performance material in the civil engineering.
基金Foundation Ireland(SFI)and the European Regional Development Fund(Grant No.13/RC/2073).
文摘Rapid and efficient tendon fixation to a bone following trauma or in response to degenerative processes can be facilitated using a tendon anchoring device.Osteomimetic biomaterials,and in particular,bio-resorbable polymer composites designed to match the mineral phase content of native bone,have been shown to exhibit osteoinductive and osteoconductive properties in vivo and have been used in bone fixation for the past 2 decades.In this study,a resorbable,bioactive,and mechanically robust citrate-based composite formulated from poly(octamethylene citrate)(POC)and hydroxyapatite(HA)(POC-HA)was investigated as a potential tendon-fixation biomaterial.In vitro analysis with human Mesenchymal Stem Cells(hMSCs)indicated that POC-HA composite materials supported cell adhesion,growth,and proliferation and increased calcium deposition,alkaline phosphatase production,the expression of osteogenic specific genes,and activation of canonical pathways leading to osteoinduction and osteoconduction.Further,in vivo evaluation of a POC-HA tendon fixation device in a sheep metaphyseal model indicates the regenerative and remodeling potential of this citrate-based composite material.Together,this study presents a comprehensive in vitro and in vivo analysis of the functional response to a citrate-derived composite tendon anchor and indicates that citrate-based HA composites offer improved mechanical and osteogenic properties relative to commonly used resorbable tendon anchor devices formulated from poly(L-co-D,l-lactic acid)and tricalcium phosphate PLDLA-TCP.
