不同配筋率下UHPC单向板受弯性能研究  

Study on flexural performance of one⁃way UHPC slab with different reinforcement ratios

作　　者：杨明 王波 YANG Ming;WANG Bo(CCCC Second Highway Consultants Co.,Ltd.,Wuhan 430056,China)

机构地区：[1]中交第二公路勘察设计研究院有限公司,武汉430056

出　　处：《建筑结构》2025年第4期74-80,共7页Building Structure

基　　金：广东省省级科技计划项目2021B1111610002。

摘　　要：由于缺乏统一标准,如何通过设置超高性能混凝土(UHPC)层的经济厚度及合理的配筋来发挥结构的整体性能仍有待进一步研究。为此,进行了6组UHPC单向板和2组钢纤维混凝土(SFRC)单向板受弯性能试验。结果表明:UHPC单向板的开裂荷载、极限荷载以及结构刚度均比SFRC单向板大,表现出更优越的抗裂、受弯性能与延性;UHPC单向板的受弯性能受钢筋单、双层设置形式的影响较小,而随配筋率与厚度的增加而显著提高;当配筋率从0增大至2.61%、3.92%与5.22%时,UHPC单向板的开裂荷载分别提高25%、50%和75%,极限弯矩分别提高107%、128%与175%;采用美国标准计算的UHPC单向板的极限弯矩结果与试验值较为吻合,而随配筋增多,开裂弯矩计算值与试验值相差较大;板厚的增加能够明显提高UHPC单向板开裂荷载,而极限承载力受配筋率影响更为显著,但配筋率接近超筋梁配筋时,配筋率对极限承载力的增加已不再具备经济性。Due to the lack of uniform standards,how to exert the overall performance of the structure by setting the economic thickness of the ultra⁃high performance concrete(UHPC)layer and reasonable reinforcement remains to be further studied.To this end,six groups of one⁃way UHPC slabs and two groups of one⁃way steel fiber concrete(SFRC)slabs were tested for flexural performance.The results show that the cracking load,ultimate load and structural stiffness of one⁃way UHPC slabs are larger than those of one⁃way SFRC slabs,showing better crack resistance,flexural performance and ductility.The flexural performance of one⁃way UHPC slabs is less affected by the single and double layer setting forms of steel bars,but significantly improved with the increase of reinforcement ratio and thickness.When the reinforcement ratio increases from 0 to 2.61%,3.92%and 5.22%,the cracking load of one⁃way UHPC slabs increases by 25%,50%and 75%respectively,and the ultimate bending moment increases by 107%,128%and 175%respectively.The ultimate bending moment of one⁃way UHPC slabs calculated by American standard is in good agreement with the experimental value,and with the increase of reinforcement,the calculated value of cracking moment is greatly different from the experimental value.The increase of slab thickness can significantly improve the cracking load of one⁃way UHPC slabs,and the ultimate bearing capacity is more significantly affected by the reinforcement ratio.However,when the reinforcement ratio is close to that of the super⁃reinforced beam,the increase of the reinforcement ratio on the ultimate bearing capacity is no longer economical.

关 键 词：超高性能混凝土 单向板 配筋 抗弯性能 破坏机理 

分 类 号：TU375[建筑科学—结构工程]