高陡岩质边坡上桥梁基桩模型试验研究

高陡岩质边坡上桥梁基桩的受力性状极为复杂,既要承受上部荷载,又要抵抗桩侧滑坡推力,具有承重与阻滑双重功能,且由于陡坡的存在,使得该类基桩与平地上无坡度的基桩在承载机理上存在明显差异。以竖向荷载下基桩挠曲微分方程为基础,采用方程分析法导出了高陡岩质边坡上桥梁桩基模型试验的相似准则,并以该准则为指导,开展陡坡桩基室内模型试验。通过室内试验得到了不同组合荷载及加载方式条件下基桩弯矩及桩顶水平位移的情况,探讨了该类桩受力性状,并获得基桩桩侧土压力、抗力分布形态及影响范围的情况,以助于更深入地了解陡坡上桥梁基桩的荷载传递机理,具有一定的理论和工程应用价值。

Model tests on bridge pile foundation in high and steep rock slopes

The bridge pile foundation in high-steep rock slopes has double functions that will not only bear the load from the superstructure,but also counteract the landslide-thrust from the pile foundation side.The bearing mechanism of piles in high-steep rock slopes is much more complex than that of piles in the flat because of the steep rock slope.Based on the bending differential equation of pile foundation under vertical load piles,the similarity rule of the bridge pile foundation in steep slopes is deduced and model tests are implemented on the basis of the similarity rule.The moment and horizontal displacements are achieved through different combined loads and load methods,the working mechanism of the pile foundation is discussed,and the distribution and influence zone of soil thrust and resistance is acquired by model tests.It will help to deeply understand the load transfer mechanism.