Durability of Fiber Reinforced Polymer Materials in Accelerated and Modeled Concrete Environments

9812745Porter该项目解决了用于取代结构混凝土中传统钢筋的纤维增强聚合物（FRP）材料的长期耐久性和加速老化特性的重要问题。这些类型的材料是替代MRI应用、海洋环境以及许多其他民用和军用基础设施用途中的钢筋和预应力筋的优秀候选材料。这些材料显示出很大的前景，因为它们是非金属的，因此被认为通常没有钢所易受的腐蚀问题。该研究的目标涉及额外的创新性短期实验室测试，以准确，可靠地预测FRP材料的长期性能。将对使用长纤维玻璃钢绞线嵌入乙烯基酯基质中的FRP钢筋进行检查。本研究将研究FRP材料在暴露于混凝土环境和吸湿解吸循环时劣化和损坏过程的基本性质，这些过程将用于研究创新方法来模拟这些过程的老化，并通过加速老化技术准确预测长期行为。在研究FRP加固混凝土的长期耐久性的步骤包括表征混凝土孔隙水的性质，并将此模型与以前开发的模型进行比较。本次调查的范围包括研究FRP钢筋暴露在混凝土内的常见环境条件的影响。这涉及到FRP筋的测试和分析，包括控制样本。范围包括在假定老化条件下对试样施加应力以及未施加应力的试样。在老化过程后，样本将在拉伸和弯曲方面失效，以确定由于环境条件导致的强度损失。

9812745PorterThis project addresses important issues regarding the long-term durability and accelerated aging characteritics of Fiber Reinforced Polymer (FRP) materials used for the replacement of conventional steel reinforcing in structural concrete. These type of materials are excellent candidates to replace steel reinforcing bars and prestressing tendons in MRI applications, marein environments, and many ofther civilian and military infrastructure uses. These materials show great promise because they are non-metallic and therefore are believed to be generally free of the corrosive problems to which steel has been suseptible. The objectives of the reserch involve additional innovative short-term laboratory tests that allow accurate, reliable prediction of long-term performance of FRP materials. FRP reinforcing bars constructed using long-fiber glass strands embedded in a vinyl ester matrix will be examined. This research will examine the fundamental nature of the deterioration and damage proceses in FRP materials when exposed to concrete environments and moisture absorption desorption cycles which will be used to look at innovative ways to model the behaviro of these processes and accurately predict the long-term behavior by accelerated aging techniques. Steps involve in studying the long-term durability of FRP reinforcement in concrete include characterizing the nature of concrete porewater and comparing this added model to previously developed models. The scope of this investigation involves studying the effects of FRP reinforcing bars exposed to common environmental conditions within concrete. This involves the test and analysis of FRP reinforcing bars, including control specimens. The scope includes subjecting specimens to stress under assumed aging conditions as well as unstressed specimens. Following subjection to the aging process, specimens will be failed in tension and flexure to determine the loss in strength due to the environmental conditions.