超长预应力管桩施工实践

Construction Practice of Super-long Pre-stressed Tubular Pile

摘要:

根据《先张法预应力混凝土管桩》（GB 13476-1999）、浙江省建筑标准《设计结构标准图集》（2002浙G22）的规定，预应力管桩摩擦桩的长径比≯100，当用于端承桩或摩擦端承桩且须穿过一定厚度较硬土层时，其长径比≯80。理想·伊萨卡管桩工程最长的设计桩长60 m，桩径为550及600 mm，采用4节15 m的桩连接，长径比超过100，属于超长预应力管桩且地基土层主要为粉土与砂土。通过杭州理想·伊萨卡管桩工程实例，对砂层、粉土层中超长预应力管桩的施工工艺的制定进行了有益的探索。

Abstract:

Based on “Pre-tensioned Pre-stressed Concrete Tubular Pile”（GB 13476-1999）and “Design Structure Standard Alta”（2002 Zhejiang G22）, the length-diameter ratio of frictional pre-stressed tube pile should less than 100, and the length-diameter ratio of end bearing pile or frictional end bearing pile should less than 80 while getting through a certain thickness in hard soil. The paper introduced an engineering case of super-long pre-stressed tubular pile in silty and sandy soil with the longest design pile length of 60m,diameter of 550mm and 600mm, connected by 4 piles of 15m, the length-diameter ratio was more than 100. Beneficial exploration was made on construction of super-long pre-stressed tube pile in sand and silt layer based on this case in Hangzhou City.