Research status and future directions of defect detection in grouted splice sleeves: A review

Abstract

At present, grouted splice sleeves are widely used in assembly-type building connections due to their exceptional structural performance. However, various grout defects may arise, including grout leakage, interfacial debonding, internal voids, reinforcement eccentricity, and poor grout, as a result of the combined impact of human, environmental, technical, and equipment risks. These defects can lead to a decrease in the load-bearing capacity and durability of the structure. Therefore, it is crucial to develop efficient detection methods for grouted splice sleeves to ensure grout quality. This study provides a comprehensive and up-to-date review of the defect detection techniques for grouted splice sleeves.First, the typical applications and types of grout defects in grouted splice sleeves are reviewed. Various detection methods are categorized into direct and indirect detection (mechanical waves and electromagnetic waves) methods, and their current application status and detection principles are systematically summarized. Direct detection methods employ tools that can directly contact the grout defects themselves, while the equipment used in mechanical wave- and electromagnetic wave-based detection methods cannot directly touch the grout but rather is placed outside the steel sleeve or concrete protective layer to indirectly measure grout defects. Furthermore, a systematic comparison and in-depth analysis of the advantages and disadvantages, detection targets, and presentation modes of various detection techniques are conducted.The findings of this study can help guide researchers and engineers in the development and application of grout defect detection techniques for grouted splice sleeves.