Based on the concept of functionally graded concrete,UHTCC(ultrahigh toughness cementitious composites)material with excellent crack-controlling ability is strategically substituted for part of the concrete,which surr...Based on the concept of functionally graded concrete,UHTCC(ultrahigh toughness cementitious composites)material with excellent crack-controlling ability is strategically substituted for part of the concrete,which surrounds the main longitudinal reinforcement in a reinforced concrete member.Investigations on bending behavior of such a functionally graded composite beam crack-controlled by UHTCC(abbreviated as UHTCC-FGC beam)have been carried out.After establishing a theoretical cal-culation model,the paper discusses the results of four-point bending experiment on long composite beams without web reinforcement,and validates the theoretical formulae through experimental results of UHTCC-FGC beams with different thicknesses of UHTCC layer.Besides improving bearing capacity and saving steel reinforcements,the results indicate that UHTCC-FGC beams can also effectively control the deformation and enhance the ductility of members.At last,the optimal thickness of UHTCC layer in UHTCC-FGC beams has been confirmed,which can not only save materials and improve mechanical performance of members,but also be very effective in preventing corrosion-induced damage and enhancing the durability of members by controlling crack width below 0.05mm under service conditions.展开更多
目的基于VOSviewer、CiteSpace对针灸治疗功能性消化不良的随机对照试验(RCT)文献进行可视化分析,总结该领域的研究现状、热点及未来发展趋势。方法检索中国知网、万方数据知识服务平台、维普网、中国生物医学文献数据库、PubMed、Web o...目的基于VOSviewer、CiteSpace对针灸治疗功能性消化不良的随机对照试验(RCT)文献进行可视化分析,总结该领域的研究现状、热点及未来发展趋势。方法检索中国知网、万方数据知识服务平台、维普网、中国生物医学文献数据库、PubMed、Web of Science核心合集数据库中有关针灸治疗功能性消化不良的RCT文献,检索时限为2004年1月至2023年12月,利用VOSviewer、CiteSpace对该领域作者、机构、关键词进行可视化分析。结果最终纳入中文文献565篇、英文文献12篇。发文量排名前3位的作者为周利、刘存志、常小荣;发文最多的机构为湖北中医药大学;主要关键词为功能性消化不良、针刺、临床疗效;关键词聚类共10类;突现强度最大的关键词为辨证。结论针灸治疗功能性消化不良临床RCT研究目前正处于蓬勃发展阶段,不同疗法及穴位的选择是当前研究热点,研究趋势包括评价指标的选取及效应机制的探索。展开更多
基金Supported by the Key Program of the National Natural Science Foundation of China(Grant No.50438010)the Research and Application Programs of Key Technolo-gies for Major Constructions in the South-North Water Transfer roject Construction in China(Grant No.JGZXJJ2006-13)
文摘Based on the concept of functionally graded concrete,UHTCC(ultrahigh toughness cementitious composites)material with excellent crack-controlling ability is strategically substituted for part of the concrete,which surrounds the main longitudinal reinforcement in a reinforced concrete member.Investigations on bending behavior of such a functionally graded composite beam crack-controlled by UHTCC(abbreviated as UHTCC-FGC beam)have been carried out.After establishing a theoretical cal-culation model,the paper discusses the results of four-point bending experiment on long composite beams without web reinforcement,and validates the theoretical formulae through experimental results of UHTCC-FGC beams with different thicknesses of UHTCC layer.Besides improving bearing capacity and saving steel reinforcements,the results indicate that UHTCC-FGC beams can also effectively control the deformation and enhance the ductility of members.At last,the optimal thickness of UHTCC layer in UHTCC-FGC beams has been confirmed,which can not only save materials and improve mechanical performance of members,but also be very effective in preventing corrosion-induced damage and enhancing the durability of members by controlling crack width below 0.05mm under service conditions.
文摘目的基于VOSviewer、CiteSpace对针灸治疗功能性消化不良的随机对照试验(RCT)文献进行可视化分析,总结该领域的研究现状、热点及未来发展趋势。方法检索中国知网、万方数据知识服务平台、维普网、中国生物医学文献数据库、PubMed、Web of Science核心合集数据库中有关针灸治疗功能性消化不良的RCT文献,检索时限为2004年1月至2023年12月,利用VOSviewer、CiteSpace对该领域作者、机构、关键词进行可视化分析。结果最终纳入中文文献565篇、英文文献12篇。发文量排名前3位的作者为周利、刘存志、常小荣;发文最多的机构为湖北中医药大学;主要关键词为功能性消化不良、针刺、临床疗效;关键词聚类共10类;突现强度最大的关键词为辨证。结论针灸治疗功能性消化不良临床RCT研究目前正处于蓬勃发展阶段,不同疗法及穴位的选择是当前研究热点,研究趋势包括评价指标的选取及效应机制的探索。
