During their long-term service, wastewater treatment plants deteriorate due to rebar corrosion in concrete structures. This paper presents a case study of ground penetrating radar (GPR) survey performed on a reinforced concrete (RC) structure in sieving unit of the wastewater treatment plant in the City of Fortaleza, Brazil. The RC structure was subjected to both the sulfuric acid attack from the oxidation of hydrogen sulfide present in the wastewater gas and the cyclic dry–wet salt-fog environment due to its proximity to the ocean. The survey results suggest that the amplitude of electromagnetic waves from a GPR scan and the determined dielectric permittivity values can be used to monitor steel rebar corrosion in a concrete structure by rapidly detecting any growth of inherent faults. The results indicate that the rebar condition can be assessed through slices at different times/depths obtained from a three-dimensional (3D) survey. Based on this study, it is recommended that the upper RC slabs in sieving unit of the plant be demolished and the lower slabs be preserved.

在长期服务期间，废水处理厂由于混凝土结构中的钢筋腐蚀而恶化。本文介绍了对巴西福塔雷萨市污水处理厂筛分装置中钢筋混凝土结构进行地面探查雷达调查的案例研究。RC结构既受到来自废气中存在的硫化氢的氧化的硫酸侵蚀，又由于其靠近海洋而遭受循环干湿盐雾环境的影响。调查结果表明，通过GPR扫描产生的电磁波幅度和确定的介电常数值可用于通过快速检测固有缺陷的增长来监视混凝土结构中的钢筋腐蚀。结果表明，可以通过从三维（3D）调查获得的不同时间/深度的切片来评​​估钢筋状况。根据这项研究，建议拆除工厂筛分装置的上部RC板，并保留下部的板。