岩溶发育区毗邻地下重要构筑物大直径桩基成桩技术

Discussion on Construction Technology of Large Diameter Piles Adjacent toImportant Underground Structure in Intensified Karst Development Area

岩溶发育地区桩基施工技术是保证桩基施工安全与成桩质量的关键环节之一。由于城市集约用地的建设趋势,高架桥和地下构筑物立体交叉的情况越来越多。结合岩溶发育区高速公路桥梁桩基直径大、毗邻地下重要构筑物的情况,采用低成本且高效率的管波溶洞勘探技术、岩溶处理技术和桩基施工技术,在有效保证毗邻地下重要构筑物安全的前提下,安全、高效地完成了岩溶发育区大直径桩基施工。针对溶洞发生漏浆、岩石裂隙涌水等突发情况,分别创新优化了不同工况的针对性回填材料比例和涌水处理方案,在工程实践中取得了较好的效果,可为后续类似工程提供参考借鉴。

The construction technology of pile foundation in Karst Area is the key factor for the safety and quality assurance,due to the trend of intensive urban land use,there are more and more interchanges between viaducts and underground structures.At present,there are many researches on the construction technology of Karst pile foundation in China,but very few researches of them are on the construction technology of pile foundation in Karst area adjacent to underground structures.With the combined applications of low cost and high efficiency Karat cave exploration and treatment technology as well as pile construction technology,in this paper,the construction of large diameter piles adjacent to underground important structure in intensified Karst development area has beenefficiently completed,and the safety of underground structurehas been ensured.In view of the sudden situations such as slurry leakage and rock fissure water gushing in Karst caves,in this paper,the proportion of targeted backfill materials and water gushing treatment schemes under different working conditionshave been innovatively optimized,and good results through practicehave been achieved,which can provide good reference for subsequent similar projects.