摘要
通过对5根不同翼缘尺寸的地聚物混凝土T形梁和1根普通混凝土T形梁进行四点弯曲试验,研究了翼缘宽度和厚度对地聚物混凝土T形梁抗弯性能的影响,以及与普通混凝土T形梁的差异。研究结果表明:地聚物混凝土T形梁的抗弯极限荷载、屈服荷载、裂缝行为及失效模式与普通混凝土T形梁相似,且延性更优,但其跨中受拉纵筋应变较大,刚度、开裂荷载和最大裂缝宽度限值下的承载力较低。随着翼缘宽度从200 mm增大到500 mm,地聚物混凝土T形梁的刚度、屈服荷载、抗弯极限荷载、延性和在最大裂缝宽度限值下的承载力均增大,跨中受拉纵筋应变减小,开裂荷载无明显变化,但越宽的翼缘宽度能有效承担荷载的也只是靠近腹板的一部分宽度。增大翼缘厚度对地聚物混凝土T形梁抗弯性能的影响与增大翼缘宽度基本一致,但其对最大裂缝宽度限值下的承载力提高效果显著。规范GB 50010—2010和ACI 318—19的正截面受弯承载力设计公式适用地聚物混凝土T形梁,GB 50010—2010的预测更精确,ACI 318—19的安全储备更高。
The influence of flange width and thickness on the flexural behavior of geopolymer concrete T-beams was investigated by the four-point bending test of five geopolymer concrete T-beams with different flange sizes and one ordinary concrete T-beam.Meanwhile,the difference between geopolymer concrete and ordinary concrete T-beam were evaluated.The results show that the flexural ultimate load,yield load,crack behavior and failure mode of geopolymer concrete T-beams are similar to those of ordinary concrete T-beams.The ductility of geopolymer concrete T-beam is better than that of ordinary concrete T-beam.However,the strain of the longitudinal reinforcement in mid span tension is relatively larger,and the stiffness,crack loading,and bearing capacity of geopolymer concrete T-beam under the maximum crack width limit are relatively lower.As the flange width increases from 200 mm to 500 mm,the stiffness,yield load,flexural ultimate load,ductility,and bearing capacity under the maximum crack width limit of the geopolymer concrete T-beam all increase.The strain of the tensile longitudinal reinforcement at the mid span decreases,and there is no significant change in cracking load.However,the wider the flange width,only a part of the width close to the web can effectively bear the load.The effect of increasing flange thickness on the flexural behavior of geopolymer concrete T-beams is basically the same as that of increasing flange width.However,its effect on improving the bearing capacity under the maximum crack width limit is significant.The design formulas for the normal section flexural bearing capacity of GB 50010—2010 and ACI 318—19 are applicable to geopolymer concrete T-beams.The prediction of GB 50010—2010 is more accurate,and the safety reserve of ACI 318—19 is higher.
作者
徐勇
毛宇光
刘翼玮
苏捷
杜运兴
史才军
XU Yong;MAO Yuguang;LIU Yiwei;SU Jie;DU Yunxing;SHI Caijun(Key Laboratory for GACEM&ATH,College of Civil Engineering,Hunan University,Changsha 410082,Hunan,China;International Innovation Center for G&ACEMH,College of Civil Engineering,Hunan University,Changsha 410082,Hunan,China;Key Laboratory of BS&EE of the Ministry of Education,Hunan University,Changsha 410082,Hunan,China)
出处
《重庆交通大学学报（自然科学版）》
CAS
CSCD
北大核心
2024年第2期1-9,23,共10页
Journal of Chongqing Jiaotong University(Natural Science)
基金
国家自然科学基金项目(51638008)。
关键词
桥梁工程
结构工程
地聚物混凝土
T形梁
翼缘宽度
翼缘厚度
抗弯性能
bridge engineering
structural engineering
geopolymer concrete
T-beams
flange width
flange thickness
flexural behavior
