现代隧道技术
現代隧道技術
현대수도기술
Modern Tunnelling Technology
2015年
5期
145-151
,共7页
杨春山%莫海鸿%陈俊生%李亚东%侯明勋
楊春山%莫海鴻%陳俊生%李亞東%侯明勛
양춘산%막해홍%진준생%리아동%후명훈
盾构隧道%近距离下穿既有隧道%位移影响%管片张开量%数值模拟%双面弹性地基梁%等效连续化模型
盾構隧道%近距離下穿既有隧道%位移影響%管片張開量%數值模擬%雙麵彈性地基樑%等效連續化模型
순구수도%근거리하천기유수도%위이영향%관편장개량%수치모의%쌍면탄성지기량%등효련속화모형
Shield tunnel%Approaching construction under existing tunnel%Displacement influence%Segment opening%Numerical analysis%Double-sided elastic foundation beam%Equivalent continuous model
盾构隧道掘进对邻近建筑物影响问题一直是个工程难题. 文章采用有限元法对近距离下穿盾构隧道施工进行模拟,分析了新建隧道动态掘进时既有隧道的位移变化规律. 基于双面弹性地基梁理论与盾构隧道纵向等效连续化模型,推导了既有地铁隧道受新建盾构隧道开挖影响管片张开量的计算公式,计算分析了管片张开量分布规律.分析结果表明:盾构掘进时对上覆斜交隧道影响区域主要在新建隧道轴线两侧2D(盾构直径)范围内;既有地铁的竖向位移主要分布在盾构掘进面前方2D和盾尾后1.5D范围内产生; 既有地铁盾构隧道管片在新建隧道轴线正上方左右两个接头处张开显著,出现塑性变形. 工程中需以既有地铁与下穿隧道相交处为轴,对既有地铁隧道侧向2D范围及两隧道间土层进行局部加固,以防新建隧道掘进引起既有地铁隧道纵向变形与张开过大.
盾構隧道掘進對鄰近建築物影響問題一直是箇工程難題. 文章採用有限元法對近距離下穿盾構隧道施工進行模擬,分析瞭新建隧道動態掘進時既有隧道的位移變化規律. 基于雙麵彈性地基樑理論與盾構隧道縱嚮等效連續化模型,推導瞭既有地鐵隧道受新建盾構隧道開挖影響管片張開量的計算公式,計算分析瞭管片張開量分佈規律.分析結果錶明:盾構掘進時對上覆斜交隧道影響區域主要在新建隧道軸線兩側2D(盾構直徑)範圍內;既有地鐵的豎嚮位移主要分佈在盾構掘進麵前方2D和盾尾後1.5D範圍內產生; 既有地鐵盾構隧道管片在新建隧道軸線正上方左右兩箇接頭處張開顯著,齣現塑性變形. 工程中需以既有地鐵與下穿隧道相交處為軸,對既有地鐵隧道側嚮2D範圍及兩隧道間土層進行跼部加固,以防新建隧道掘進引起既有地鐵隧道縱嚮變形與張開過大.
순구수도굴진대린근건축물영향문제일직시개공정난제. 문장채용유한원법대근거리하천순구수도시공진행모의,분석료신건수도동태굴진시기유수도적위이변화규률. 기우쌍면탄성지기량이론여순구수도종향등효련속화모형,추도료기유지철수도수신건순구수도개알영향관편장개량적계산공식,계산분석료관편장개량분포규률.분석결과표명:순구굴진시대상복사교수도영향구역주요재신건수도축선량측2D(순구직경)범위내;기유지철적수향위이주요분포재순구굴진면전방2D화순미후1.5D범위내산생; 기유지철순구수도관편재신건수도축선정상방좌우량개접두처장개현저,출현소성변형. 공정중수이기유지철여하천수도상교처위축,대기유지철수도측향2D범위급량수도간토층진행국부가고,이방신건수도굴진인기기유지철수도종향변형여장개과대.
The effects of shield tunnelling on adjacent buildings have long been a serious problem. In this paper, the approaching construction of an underlying shield tunnel was simulated by the finite element method and the displacement variation law of the existing metro tunnel during construction of the underlying shield tunnel was analyzed. Based on the double-sided elastic foundation beam theory and the shield tunnel longitudinal equivalent continuous model, a calculation equation for the segment openings of the existing metro tunnel affected by con-struction of the new shield tunnel was deduced and the distribution law for the segment openings was analyzed. The analysis results show that: 1) the area of the overlying, obliquely crossing metro tunnel affected by shield tunnel construction is mainly located in the range of 2D (D=tunnel diameter) on both sides of the new shield tun-nel axis; 2)the vertical displacement distribution of the existing metro tunnel is mainly within the range of 2D a-head of the working face and 1.5D behind the shield tail;3) the segment opening of the existing metro tunnel ap-pears obviously at the two joints (left and right) directly above new the shield tunnel axis and is accompanied by plastic deformation; and 4) the area within 2D of the sides of the existing metro tunnel and the soil layer between the two tunnels should be locally reinforced to prevent longitudinal deformation and excessive segment opening of the existing metro tunnel associated with the new shield tunnelling.