In this paper the alkali-activated slag cementitious materials(AASCM)which strength at 600 ℃ is larger than that of AASCM at room temperature,were prepared to paste CFRP sheets to strengthen four simply supported unb...In this paper the alkali-activated slag cementitious materials(AASCM)which strength at 600 ℃ is larger than that of AASCM at room temperature,were prepared to paste CFRP sheets to strengthen four simply supported unbonded prestressed composite beams encased circular steel tube truss after ultimate limit state.Test on flexural behavior of these four beams was performed.Moreover,normal section load-bearing capacity of these beams and the curve load-deflection at mid-span were obtained.Experimental results show that it is feasible to strengthen concrete members with CFRP sheets bonded with AASCM.Based on the experimental results and theoretical study,computational method of stiffness is proposed for calculating bending rigidity and normal section load-bearing capacity of concrete simply supported beams strengthened with CFRP sheets bonded with AASCM.Formula of bending rigidity calculation was founded which results are in good agreement with testing data.展开更多
Organic epoxy matrices have been widely used in the FRP reinforcing technique, but they have serious disadvantages of poor high-temperature resistance. An inorganic adhesive is invented to replace the organic adhesive...Organic epoxy matrices have been widely used in the FRP reinforcing technique, but they have serious disadvantages of poor high-temperature resistance. An inorganic adhesive is invented to replace the organic adhesive. For the inorganic adhesive at normal temperature and different high temperatures, the microstructure and phase composition are investigated by means of X-ray diffraction （XRD） and SEM respectively. Results show that inorganic adhesive can resist at least 600 ℃ high temperature. Fire-resistance performance of inorganic adhesive can meet the requirements of fiber reinforced polymer （FRP） strengthened RC structures.展开更多
为了研究低强混凝土配筋柱在碳纤维增强聚合物(CFRP)加固后的受压行为,使用ABAQUS软件对低抗压强度的钢筋混凝土柱进行数值模拟及参数分析,采用三维实体单元和三维桁架单元分别对混凝土柱及钢筋进行建模,采用混凝土损伤塑性模型考虑基...为了研究低强混凝土配筋柱在碳纤维增强聚合物(CFRP)加固后的受压行为,使用ABAQUS软件对低抗压强度的钢筋混凝土柱进行数值模拟及参数分析,采用三维实体单元和三维桁架单元分别对混凝土柱及钢筋进行建模,采用混凝土损伤塑性模型考虑基体压缩和拉伸的损伤。结果表明:相比配筋柱,采用3 mm CFRP护套加固的低强钢筋混凝土柱的承载力提高34%。对于不同基体强度的混凝土配筋柱,CFRP护套存在最优加固厚度。展开更多
基金Sponsored by the Changjiang Scholars Program of China(Grant No.2009-37)the National Natural Science Foundation of China(Grant No.50678050)
文摘In this paper the alkali-activated slag cementitious materials(AASCM)which strength at 600 ℃ is larger than that of AASCM at room temperature,were prepared to paste CFRP sheets to strengthen four simply supported unbonded prestressed composite beams encased circular steel tube truss after ultimate limit state.Test on flexural behavior of these four beams was performed.Moreover,normal section load-bearing capacity of these beams and the curve load-deflection at mid-span were obtained.Experimental results show that it is feasible to strengthen concrete members with CFRP sheets bonded with AASCM.Based on the experimental results and theoretical study,computational method of stiffness is proposed for calculating bending rigidity and normal section load-bearing capacity of concrete simply supported beams strengthened with CFRP sheets bonded with AASCM.Formula of bending rigidity calculation was founded which results are in good agreement with testing data.
基金Funded by the National Natural Science Foundation of China(No.50678050)
文摘Organic epoxy matrices have been widely used in the FRP reinforcing technique, but they have serious disadvantages of poor high-temperature resistance. An inorganic adhesive is invented to replace the organic adhesive. For the inorganic adhesive at normal temperature and different high temperatures, the microstructure and phase composition are investigated by means of X-ray diffraction （XRD） and SEM respectively. Results show that inorganic adhesive can resist at least 600 ℃ high temperature. Fire-resistance performance of inorganic adhesive can meet the requirements of fiber reinforced polymer （FRP） strengthened RC structures.
文摘为了研究低强混凝土配筋柱在碳纤维增强聚合物(CFRP)加固后的受压行为,使用ABAQUS软件对低抗压强度的钢筋混凝土柱进行数值模拟及参数分析,采用三维实体单元和三维桁架单元分别对混凝土柱及钢筋进行建模,采用混凝土损伤塑性模型考虑基体压缩和拉伸的损伤。结果表明:相比配筋柱,采用3 mm CFRP护套加固的低强钢筋混凝土柱的承载力提高34%。对于不同基体强度的混凝土配筋柱,CFRP护套存在最优加固厚度。
