树脂涂层及海水浸泡对玄武岩纤维织物增强海水海砂混凝土力学性能的影响

Effects of resin coating and seawater immersion on mechanical performance of basalt textile reinforced seawater sea sand concrete

为了研究不同树脂(环氧树脂、呋喃树脂、乙烯基树脂)涂层及海水浸泡对玄武岩纤维织物增强海水海砂混凝土(BTR-SSC)力学性能的影响,采用万能试验机对各树脂涂层纤维束和海水浸泡不同时间下BTR-SSC试件进行静态拉伸试验,并通过拔出试验评估纤维-基体界面粘结性能。结合数字图像相关分析得到裂纹与应变分布,并采用扫描电镜分析损伤机制。通过界面粘结强度计算公式实现以裂纹分布和基体强度评估界面长期性能。结果表明:3种树脂对纤维束的增强效果显著且相近(32%左右),均可显著提升BTR-SSC力学性能,乙烯基树脂涂层表现最佳,抗拉性能和界面粘结性能分别提升77%和180%。海水浸泡下BTR-SSC试件力学性能明显劣化,未处理试件仅高温浸泡14天后便脆断,环氧树脂、呋喃树脂和乙烯基树脂涂层试件浸泡7天时相对未处理试件抗拉强度分别提升81%、48%和94%,浸泡28天时仍呈多裂缝开展,界面粘结性能分别损失64%、57%和55%。该成果将有助于提升BTR-SSC在海洋环境中长期性能并促进其在海工结构中的应用。

In order to study the effects of different resin(epoxy resin,furan resin,vinyl resin)coatings and seawater immersion on the mechanical properties of basalt textile reinforced seawater sea sand concrete(BTR-SSC),a universal testing machine was used to perform static tensile tests on the fiber yarns of each resin coating and the BTR-SSC specimens immersed in seawater for different time,and the fiber-matrix interface bonding performance was evaluated by pull-out test.The crack and strain distribution were obtained by digital image correlation analysis,and the damage mechanism was analyzed by scanning electron microscopy.The long-term performance of the interface was evaluated by crack distribution and matrix strength through the calculation formula of interface bond strength.The results show that the reinforcing effects of the three resins on the fiber yarns are significant and similar(around 32%),which could significantly improve the mechanical properties of BTR-SSC.The vinyl resin coating had the best performance,and the tensile properties and interfacial bonding properties are increased by 77%and 180%,respectively.The mechanical properties of BTR-SSC specimens are significantly degraded under seawater immersion.The untreated specimens are brittle after 14 days of high temperature immersion.The tensile strength of epoxy resin,furan resin and vinyl resin coated specimens increase by 81%,48%and 94%respectively after 7 days of immersion compared with untreated specimens.After 28 days of immersion,there are still multiple cracks developed,and the interfacial bonding properties are lost by 64%,57%and 55%,respectively.The results will help to improve the long-term performance of BTR-SSC in the marine environment and promote its application in marine structures.