摘要
Abstract
To solve the issue of a 500 kV high-voltage transmission tower that could not be dismantled in the short term within a deep foundation pit for a park supporting facility project,a phased construction strategy of"protection first,excavation later"was proposed to ensure construction schedule and safety.According to relevant codes,a 10-meter zone from the outer edge of the tower foundation was designated as the core protection area,where slope surface protection was implemented using mesh-reinforced shotcrete.Soil disturbance,loading,and mechanical operations within the protected area were strictly restricted at the same time.The remaining areas of the foundation pit were divided into segments and zones based on support types,and symmetric excavation was carried out following the principle of"thin layers,short segments,and time-limited support"with 24-hour real-time monitoring implemented throughout.After the relocation of the transmission tower was completed,the soil within the protected area was excavated in layers.Results show that:this approach has effectively controlled foundation pit deformation and tower foundation settlement,significantly shortening the construction duration and reducing costs while ensuring safety.It can serve as a reference for similar deep foundation pit projects constrained by demolition conditions.关键词
超高压/待拆线塔/深基坑/预留保护/分区开挖/多支护防护/风险控制/经济性Key words
ultrahigh-voltage/tower to be decommissioned/deep foundation pit/reserved protection/zoned excavation/multi-support protection/risk control/cost-effectiveness分类
建筑与水利
