A Case Study of The Performance of A Pile-Supported Bracing Method for Basement Building

Deep excavations in urban areas are highly hazardous due to extensive settling of the surrounding soil, which can lead to the failure of retaining wall systems and the consequent collapse of adjoining properties. The retaining wall and bracing system are important for completing deep excavations for a basement building project. This paper evaluates the performance of an alternative, innovative, low-cost pile-supported bracing system (PSBS) method during excavation for two-level basement construction. Assessed PSBS performance in terms of ground settlement, lateral movement of supporting systems, schedule, and cost comparison. The PSBS excavation method was designed and then implemented to construct a two-level basement using the bottom-up method. The total station was utilized to monitor three-dimensionally, like the adjacent school building, ground surface settlement, and lateral movement of supporting systems. A schedule and cost comparison were performed using internal bracing and the PSBS technique. The recorded filed data was analysed, and it found that the lateral movement of the support system, adjacent building, and ground settlement is within the allowable limit. According to the estimated results, the PSBS method reduces construction time by 272 days compared to the internal bracing system. The PSBS approach is also less expensive than internal bracing for a two-level basement.