南京江北新区中心区地下空间一期 基坑涌水事故处理与启示

Treatmentandanalysisofthefoundationpitwaterinrushincident inNanjingJiangbeiNewDistrict

摘要:

南京江北新区中心区地下空间一期基坑涌水事故是由于基坑内废桩孔回填封堵不密实,导致深部承压含水 层中承压水击穿废桩孔,造成涌水的事故.事故发生后,采用混凝土回填反压涌水,后在桩孔内注浆封堵,但均未 成功.之后经过调查和分析研究,确定采取降水方案,即降低深部承压水水位至涌水口以下,在无涌水的情况下进 行注浆封堵.该降水封堵方案实施历时１８天,成功地解决了涌水事故.本工程涌水事故的处理为类似工程提供 了有益的经验.

Abstract:

ThefoundationpitwaterinrushincidentontheundergroundspacefirstＧstageworksinthecentralareaof theJiangbeiNewDistrict,Nanjinghappenedduetolackofcompactionofthebackfillingintheabandonedpileholes inthefoundationpit,whichcausedtheconfinedwaterinthedeeppressurizedaquifertopenetratetheabandonedpile holes,leadingtothewaterinrushincident．Aftertheincident,theholeswerebackfilledwithconcretetocounter waterinrush,andthengroutedtosealoff．Butnoneofthemsucceeded．Throughinvestigationandanalysis,the dewateringprogram wasadopted,wherebythedeepconfined waterlevelwasloweredbelowthe waterinrush positionandgroutwasinjectedtosealoffwithoutthegushingwater．Thisdewateringprogramtook１８daysto successfullyresolvethewaterinrushincident,whichcanprovideusefulexperienceforsimilarprojects