Diagnosis of reinforced concrete structures by Ground Penetrating Radar survey - case study

In this paper, part of the results extracted from the consultancy project of applying GPR for pier structure diagnosis is presented. GPR survey results on pier structures of: (1) a 9m × 4m slab and (2) the side (8m × 0.35m) of a beam located at Macau Ferry Terminal, Hong Kong are discussed. This study is a preliminary study on constructing work flow of defect characterization; and the GPR results has been validated with core/open up test. Signs of delamination, cracks and damped area are determined after open-up observation. It concluded GPR as decision making tool on concrete rehabilitation scheme. It also helps in conducting rational sampling rather than random sampling for detailed investigation (e.g. coring, open-up survey, chloride and carbonation test etc.) on concrete structure.