摘要
根据已有关于厚覆盖层地区锚碇基础试验研究,分析重力式沉井锚碇基础的受力机理,并据此理论提出一种新型的悬索桥锚碇基础——根式锚碇基础。结合工程实例,通过FLAC3D数值模拟方法分析根式锚碇基础在两种假设工况(单独均布竖向荷载和水平荷载)和两种工程实际工况(锚碇施工结束和悬索桥运营阶段)的整体变位情况,初步分析根式锚碇基础的受力机理及变位值,同时结合根式沉井基础和根式锚碇基础的现场测试分析,验证该锚碇方案的可行性。分析结果表明:根式锚碇基础在群井底部反力、井壁反力和根键反力的共同作用下承担上部主缆索力,受力合理,其竖向和水平变位满足类似工程中关于锚碇变位要求及国内外相关规范规定,可作为厚覆盖层地区大跨度悬索桥的一种极具潜力的锚碇基础方案。
Domestic and overseas anchorage foundations of suspension bridges are mostly gravity anchorage foundations at present, such as super large open caisson anchorage foundation and diaphragm wall anchorage foundation. This paper introduces a new anchorage foundation-root anchorage foundation, made of many root foundations. By means of a series of scaled-down model tests of root anchorage foundations and FLAC 3D numerical simulation, this paper sums up the working mechanics of root anchorage foundation. It is found that root anchorage foundation scheme is feasible and satisfies the displacement requirements and bearing capacity requirements of suspension bridges. We also find that both the friction at the bottom of anchorage and the passive earth pressure in front of anchorage bear the load of cable tension of suspension dridge, which is different from the traditional design theory.
出处
《土木工程学报》
EI
CSCD
北大核心
2010年第11期102-113,共12页
China Civil Engineering Journal
关键词
悬索桥
锚碇
根式锚碇基础
厚覆盖层
受力机理
变位
数值模拟
suspension bridge
anchorage
root anchorage foundation
thick overburden
force-bearing mechanism
displacement
numerical simulation
