摘要
以成都地铁1号线盾构近距离穿越某建筑桩基工程为背景,建立有限元模型,研究盾构穿越施工和荷载转移措施对结构及桩基的影响。结果表明:盾构从桩端穿越时,有无采用梁包柱形式的桩基托换措施对隧道结构内力影响较小,但该措施能够有效减小被托换桩的最大沉降和各桩之间的不均匀沉降。桩基托换使距隧道较近的两桩轴力减小,距隧道较远的桩轴力增加,在所有桩体上均产生附加弯矩,但量值较小。建筑结构的最大弯矩发生在距隧道最远处的柱与右跨梁的刚接位置,桩基托换有效减小梁、柱的最大弯矩。监测数据表明,盾构穿越施工对桩基影响较小,桩基托换措施达到预期效果。
Taking shield passing closely through certain building pile foundation in Chengdu metro line 1 for background,this paper discusses the influence of shield excavation and pile foundation underpinning on adjacent pile foundation and structure.The numerical model is established to simulate the response of the construction.The results show that the structural internal force of tunnel changed little whether the pile foundation underpinning in the form of beam wrapping column had been used or not,but this measure can decrease effectively the settlement and uneven settlement of pile foundation.The pile foundation underpinning decreased the axial force of two piles adjacent to the tunnel and increased the axial force of the pile far from the tunnel,and brought the additional moment to all piles,but the value of change of inner stress is relatively small.The maximum bending moment of structure caused by excavating is located at the rigid joint between the bottom right side span beam and the pillar,and the pile foundation underpinning can decreased effectively the maximum bending moment of beam and pillar.The monitoring data show that the construction of sheild tunnel crossing has less influence to the pile and the measure of the pile foundation underpinning has acheived the desired effect.
出处
《地下空间与工程学报》
CSCD
北大核心
2010年第4期803-809,共7页
Chinese Journal of Underground Space and Engineering
关键词
盾构施工
桩基托换
数值模拟
沉降
附加弯矩
shield construction
pile foundation underpinning
numerical simulation
settlement
additional moment
