GFRP筋增强海砂珊瑚混凝土梁抗弯性能与承载力计算（修改后重投）

Flexural performance and bearing capacity calculation of GFRP bar-reinforced sea sand coral concrete beams

摘要:

海洋蕴藏着丰富的自然资源，利用海水、海砂和珊瑚制备海砂珊瑚混凝土（Sea Sand Coral Concrete, SSCC）用于工程建设，是解决传统建材资源匮乏的有效措施。玻璃纤维增强复合材料（Glass Fiber Reinforced Polymer, GFRP）筋具有良好的耐腐蚀性能，可以有效解决SSCC结构耐久性问题。针对GFRP筋增强SSCC梁抗弯性能与承载力计算研究存在不足，本文通过静力加载试验，探究纵筋直径、箍筋间距和混凝土强度等级对其破坏形态、跨中挠度、纵筋应变和极限承载力的影响规律。基于平截面假定，建立GFRP筋增强SSCC梁抗弯承载力计算公式，推导并确定受压区等效矩形应力图参数。结果表明：GFRP筋增强SSCC梁破坏形态主要为弯曲破坏。随着纵筋直径及混凝土强度等级的提升、箍筋间距的减小，GFRP筋增强SSCC梁的极限承载力逐渐提高，最大增幅分别为77.97%、33.05%、13.98%。GFRP筋增强SSCC梁抗弯承载力计算值与试验值吻合性较好，验证等效矩形应力图参数取值较为合理，所提抗弯承载力计算公式具有良好的计算精度和适用性。

Abstract:

The ocean harbors abundant natural resources. Utilizing seawater, sea sand, and coral to produce sea sand coral concrete for engineering construction serves as an effective measure to address the scarcity of traditional building materials. Glass fiber reinforced polymer reinforcement exhibits excellent corrosion resistance, effectively resolving the durability issues of SSCC structure. Given the deficiencies in existing research on the flexural performance and bearing capacity calculation of GFRP bar-reinforced SSCC beams, this study conducted static loading tests to investigate the effects of longitudinal reinforcement diameter, stirrup spacing, and concrete strength grade on failure mode, mid-span deflection, longitudinal reinforcement strain, and ultimate bearing capacity. Based on the plane section assumption, a calculation formula for the flexural bearing capacity of GFRP bar-reinforced SSCC beams was established, and the parameters of the equivalent rectangular stress diagram in the compression zone were derived and determined. The results indicate that the primary failure mode of GFRP bar-reinforced SSCC beams is bending failure. As the longitudinal reinforcement diameter increases, the stirrup spacing decreases, and the concrete strength grade rises, the ultimate bearing capacity of GFRP bar-reinforced SSCC beams gradually improves, with maximum increases of 77.97%, 33.05%, and 13.98%, respectively. The calculated flexural bearing capacity values of GFRP bar-reinforced SSCC beams show good agreement with the experimental values, verifying the rationality of the parameters of the equivalent rectangular stress diagram. The proposed flexural bearing capacity calculation formula demonstrates high accuracy and applicability.