深厚欠固结岩溶强发育地层桩基成孔施工工艺比选
摘要：龙洞堡机场T3航站楼项目桩基施工场址地层上层为最大厚度达64.2m的深厚抛填土层,地层下层岩溶见溶洞率高达20%以上,岩溶发育程度为强发育,局部区域溶洞发育高度达10～31.7m,同时存在平均厚度为4.63m的强风化地层。在该地质条件下,桩基工程大面积施工前通过对全套管管内取土成孔、全套管全回转成孔、泥浆护壁旋挖湿成孔、冲击钻成孔4种工艺进行工艺比选,最终确定全套管全回转成孔工艺为该复杂地质条件下唯一可行的施工工艺,避免使用泥浆造成污染环境,采用护筒进行有效护壁,通过充分利用旋挖钻机、全回转钻机等设备的机械性能,有效保证了桩基础施工的成桩效率、工期及质量。
关键词：桩基础深厚抛填土岩溶强发育全套管全回转施工工艺
尊敬的用户，本篇文章需要20元，点击支付交费后阅读
限时优惠福利：领取VIP会员
全年期刊、VIP视频免费!
全年期刊、VIP视频免费!
参考文献[1] 王永才.全回转全套管钻机成桩施工技术[J].石家庄铁道大学学报(自然科学版),2014,27(S1):239-241.
[2] 王晓华.强发育岩溶地区桩基础全套管全回转施工技术[J].国防交通工程与技术,2019,17(S1):55-57,29.
[3] 游天亮,吕欣豪,魏建辉,等.复杂地质条件下旋挖桩全钢护筒施工[J].施工技术,2020,49(6):54-57.
[4] 吴明州.分析灌注桩施工工艺中的冲击成孔和旋挖成孔技术[J].建材与装饰,2020(8):29-30.
[5] 张强,郑添寿,许万强.全套管振动取土灌注桩的工程应用[J].福建建筑,2008(12):51-53.
[2] 王晓华.强发育岩溶地区桩基础全套管全回转施工技术[J].国防交通工程与技术,2019,17(S1):55-57,29.
[3] 游天亮,吕欣豪,魏建辉,等.复杂地质条件下旋挖桩全钢护筒施工[J].施工技术,2020,49(6):54-57.
[4] 吴明州.分析灌注桩施工工艺中的冲击成孔和旋挖成孔技术[J].建材与装饰,2020(8):29-30.
[5] 张强,郑添寿,许万强.全套管振动取土灌注桩的工程应用[J].福建建筑,2008(12):51-53.
Comparison and Selection of Pile Foundation Pore Forming Construction Technology in Deep and Under-consolidated Formation with the Strong Karst Development
Abstract: In the pile foundation construction site of the T3 terminal project of Longdongbao Airport, the upper formation is super thick backfill with a maximum thickness of 64.2 m. The karst in the lower layer has a karst cave rate of more than 20%. The karst area belongs to strong development and the height in some areas is almost 10～31.7 m. At the same time, there is a strongly weathered stratum with an average thickness of 4.63 m. In this geological condition, before the large-scale construction of pile foundation engineering, through the comparison and selection of four kinds of technologies, i.e. soil sampling and hole forming in the whole casing pipe, full-sleeve full-rotation hole forming, mud wall rotary wet drilling and impact drilling hole forming. It is finally determined that the full-sleeve full rotation hole forming technology is the only feasible technology under this complex formation. This technology is avoided to use mud which will pollute the environment. By making full use of the mechanical properties of the rotary drilling machine, the full-sleeve and full-rotation machine and other equipment, the pile foundation construction efficiency, period and quality are effectively guaranteed within the pile hole wall protection of casing.
Keywords: piles; super thick backfill; strong karst development; full-sleeve and full-rotation; construction
887
0
0