开山石厚填土滨海场地桩基设计

Pile foundation design of coastal site with thick hillstone backfill

青岛万达东方影都酒店群位于青岛西海岸人工填海区,场地为近期采用厚度约11~16m的开山石改造回填后场地,局部有约16m厚淤泥包露出地面,下伏基岩为连续、稳定的沉积岩。针对新填场地固结沉降大,会对桩基产生较大的负摩阻力的特点,按建筑功能分区域采用不同夯击能进行地基处理;针对开山石及厚淤泥包场区成孔困难、易塌孔等特点,采用冲孔灌注桩,并采取可靠施工措施,采用后注浆技术提高承载力;在桩内钢筋上埋设钢筋应变计用于检验桩的承载力,保证桩基安全;对桩基的抗腐蚀做了专题研究;针对后期使用过程中场地沉降导致管线及道路的破坏,采取了有效处理措施。

Qingdao Wanda Oriental Cinema Hotel Group locates at artificial reclamation area of Qingdao west coast,where it is reconstructed and backfilled ground with 11 ~ 16 m thick hillstones recently.There are about 16 m thick outcrop sludge package partially.The subterrane is continuous stable sedimentary rocks.The consolidation settlement of newly reclaimed land was large and it produced big negative friction to pile foundation,so foundation treatment was carried out adopting different tamping energies according to different building function areas.It was difficult to form pores in hillstones and thick sludge package area and holes were easy to collapse in these areas,so impact-cone concrete pile was used,reliable construction measure were and post grouting technology was adopted to improve its bearing capacity.In order to accurately calculate the bearing capacity of test pile and guarantee safety of pile foundation,rebar strain meter was embedded on rebar in piles.A special study on corrosion resistance of pile foundation was conducted.Effective measures were taken for damages to pile lines and roads due to ground sedimentation.