新型桩板结构对高速铁路软基沉降控制作用离心试验

在CFG、PHC等刚性桩桩顶加设50 cm厚筏型钢筋混凝土形成板桩板结构控制深厚软土路基沉降，是高速铁路建设中提出的新型地基处理形式，以满足高标准铁路路基变形要求。通过对群桩处理的深厚软土路基在有无钢筋混凝土板时路基沉降的离心模拟，重点研究了钢筋混凝土板对路基沉降的控制作用以及桩、板与土体之间的相对变形。试验结果表明，在群桩处理地基上部铺设一定厚度的钢筋混凝土板，可以使路基整体沉降减小12 %，并使路基整体沉降更加均匀；桩端平面上部1/3桩长范围内土体由软塑状态转变为硬塑状态，密度和含水率变化显著；加载作用对路基变形影响深度大于40 m。

Centrifuge test of new pile-plate structure embankment settlement of soft soil of high-speed railway

Pile-plate structure is a new technology dealing with the soft soil foundation in high-speed railway practice in order to adapt to the strict deformation standards. This structure is composed of rigid pile like CFG ,PHC and 50cm plate on the top of piles; it can be used to control the embankment settlement of soft soil. Two centrifuge tests were done about the plate on the top of the piles to analyze the function of the plate for soft soil embankment settlement of high-speed railway. The results show：While the concrete plate is covered on the top of the piled-foundation, the soft soil embankment settlement is reduced about 12% and its settlement is more uniform. The soft soil changes from soft-plastic condition to hard-plastic; and the density and water content are changed obviously; the depth of the engineering load affected is over 40m.