黄河湿地漫滩区特殊地质桩基施工技术研究

Construction Technology of Special Geological Pile Foundation in the Yellow River Wetland Floodplain Area

在黄河湿地漫滩区特殊地质条件下,桥梁桩基施工无法保证成孔质量。针对此问题,研究分析了桥址区的地质情况,以及钻孔过程容易塌孔、缩颈的原因。在钻孔时采用打设超长钢护筒、清孔采用除砂器等新技术、新工艺,解决了桩基成孔难题。结果表明,对于深厚淤泥砂土地层的桩基施工采用长护筒穿过淤泥层,能有效避免塌孔、缩颈问题,清孔过程增加除砂器,能较快地降低泥浆的含砂率,缩短清孔时间,减小孔底沉渣厚度,达到快速灌注水下混凝土的目的。对于类似地质条件下的桩基施工具有指导作用。

The article focuses on the problem that the construction of bridge pile foundations cannot guarantee the quality of drilling under special geological conditions in the Yellow River wetland floodplain area.It studies and analyzes the geological conditions of the bridge site area and the reasons for easy collapse and necking during the drilling process.New technologies and processes such as drilling ultra long steel casing and using sand removers for hole cleaning are used to solve the problem of pile foundation drilling.The results show that for the construction of pile foundations in deep silt and sandy soil layers,using a long casing through the silt layer can effectively avoid problems such as collapse and necking.Adding a sand remover during the hole cleaning process can quickly reduce the sand content of the mud,shorten the cleaning time,reduce the thickness of sediment at the bottom of the hole,and achieve the goal of quickly pouring underwater concrete.It has guiding significance for pile foundation construction under similar geological conditions.