桩端后压浆在苏通大桥基础工程中的应用与研究

桩端后压浆技术目前在我国已得到了广泛应用，但多用于城市高层建筑的桩基中，在桥梁特别是在大型桥梁工程中的应用还缺乏成熟的经验。通过苏通大桥19根试桩和主桥、辅桥494根大直径深长桩首次运用U管压浆的成功实践，揭示了压浆的作用机理，提出了实用的理论计算公式，研究了U管压浆装置和成套的施工工艺及质量控制标准，并采用CT检测和承载力自平衡对比试验等手段，有力地验证了压浆取得的效果，值得在类似工程中借鉴和参考。

Application and Research of Pile Tip Grouting on Sutong Bridge Foundation

Pile tip grouting technique has been widely adopted in China, especially in pile foundation of high building. As for bridge construction esp. large-scale bridge construction, there is little experience in its application. This article explains the operation mechanism of grouting based on the successful practice of U-pipe grouting adopted in Sutong Bridge project, i.e. 19 trial piles and 494 large-diameter long piles both for main bridge and auxiliary bridge. This article also introduces practical calculation formula and presents the research results of U-pipe grouting device and a whole set of construction workmanship and quality control standards. Finally it effectively identifies the good results of grouting with means of CT inspection and bearing capacity comparison.