岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
4期
1084-1094
,共11页
压入式沉井%沉降%管线%现场监测%环境控制
壓入式沉井%沉降%管線%現場鑑測%環境控製
압입식침정%침강%관선%현장감측%배경공제
jacked open caisson%settlement%pipeline%field measurement%environmental impact control
结合工程实例,介绍软土中压入式沉井的施工技术并研究其对周边环境的影响。对沉井压沉过程中周边土体及管线的监测数据进行分析,结果表明:压沉施工能有效控制沉井的几何姿态,保持下沉速度稳定,但具有一定的挤土效应;沉井下沉初期挤土效应占主导地位,开挖效应随下沉深度的增加逐渐显著;土体水平位移和地表沉降均随沉井下沉深度 H 的增加而增大;地表沉降呈三角形分布,影响范围约为1.7H;土体分层沉降中,淤泥质粉质黏土的单位沉降量最大;管线沉降可控制在毫米级。基于对无量纲化地表沉降数据的拟合分析,提出了分别采用指数函数和二折线表示的压入式沉井周边地表沉降经验公式,并用工程实例验证了其合理性。
結閤工程實例,介紹軟土中壓入式沉井的施工技術併研究其對週邊環境的影響。對沉井壓沉過程中週邊土體及管線的鑑測數據進行分析,結果錶明:壓沉施工能有效控製沉井的幾何姿態,保持下沉速度穩定,但具有一定的擠土效應;沉井下沉初期擠土效應佔主導地位,開挖效應隨下沉深度的增加逐漸顯著;土體水平位移和地錶沉降均隨沉井下沉深度 H 的增加而增大;地錶沉降呈三角形分佈,影響範圍約為1.7H;土體分層沉降中,淤泥質粉質黏土的單位沉降量最大;管線沉降可控製在毫米級。基于對無量綱化地錶沉降數據的擬閤分析,提齣瞭分彆採用指數函數和二摺線錶示的壓入式沉井週邊地錶沉降經驗公式,併用工程實例驗證瞭其閤理性。
결합공정실례,개소연토중압입식침정적시공기술병연구기대주변배경적영향。대침정압침과정중주변토체급관선적감측수거진행분석,결과표명:압침시공능유효공제침정적궤하자태,보지하침속도은정,단구유일정적제토효응;침정하침초기제토효응점주도지위,개알효응수하침심도적증가축점현저;토체수평위이화지표침강균수침정하침심도 H 적증가이증대;지표침강정삼각형분포,영향범위약위1.7H;토체분층침강중,어니질분질점토적단위침강량최대;관선침강가공제재호미급。기우대무량강화지표침강수거적의합분석,제출료분별채용지수함수화이절선표시적압입식침정주변지표침강경험공식,병용공정실례험증료기합이성。
Based on the engineering case of a pipe-jacking working shaft sunk with the aid of caisson jacks in soft clay, the construction technology is presented and the effects on surrounding environment are studied. According to analysis of the soil mass and pipeline monitoring data during the jacked sinking process, some conclusions are drawn as follows. The jacked open caisson construction method can control the attitude of the open caisson and stabilize the sinking speed effectively;but it also squeezes the soil. At the preliminary stage of open caisson sinking, the compacting effect is significant and the excavation effect becomes more notable as the open caisson sinking deeper. The subsurface horizontal displacements and surface settlements grow along with the increase of the sinking depth H. The ground surface settlement profile is of spandrel type with an influence zone of 1.7H. Among layered settlements the unit settlement of the soft silty clay is the largest. The pipeline settlements are controlled in the millimeter level. Based on data fitting of the dimensionless surface settlements, an empirical method either in the form of exponential function or bilinear curve to predict the ground surface settlement caused by jacked open caisson construction is proposed, which is verified through two case studies.