Full-scale experiments and modeling of precast two-wall-in-one diaphragm wall components for oceanic artificial cities

Abstract

An oceanic artificial city built by reclamation is an important solution for Hong Kong to solve the land supply conflicts. Traditional cast-in-situ enclosure structures face challenges for adapting to ocean geology, climate and environment. This study thus proposed a precast two-walls-in-one diaphragm wall (PTDW). This study first conducted a full-scale experiment for PTDW. Second, numerical studies of PTDW were performed. Third, a PTDW Bending-performance Assessment Model (PTDW-BAM) was developed. Finally, the parameter analysis and decision making were performed. The main conclusions are (1) PTDW using welded joints presented a resilient damage pattern. The joint damage was slighter and lagged behind the hollow section. (2) The PTDW components with welded joint constraint exhibited high adaptability to the oceanic artificial city project. The damage pattern exhibited joint closure and cracks without penetration. (3) Hollow section parameters are central for the bending performance of PTDW. PTDW-BAM comprehensively designed the hollow section parameters and obtained the optimal parameters. (4) PTDW-BAM has a designable and flexible parameter decision-making capability for oceanic artificial city projects. The results of PTDW-BAM in the case study presented resilience, weight reduction and tightness. This achievements provide green products and assessment tool for the oceanic artificial city construction in Hong Kong.