Research Initiation: Seismic Behavior of Tiedback RetainingWalls

锚固式挡土墙以前主要用来支撑临时开挖的土方。然而，这种类型的墙体结构用于永久性结构最近变得越来越普遍，特别是沿公路交汇处和海岸线结构。与传统的悬臂墙和重力墙相比，这种结构的优点包括大墙高（超过50英尺）的成本更低，施工更容易。然而，目前还没有合理的设计程序用于考虑地震荷载的这些墙。由于传统上，回扎墙被用作临时结构，因此很少有研究针对此类结构的抗震设计。本研究项目是对柔性后拉式挡土墙的地震反应进行分析研究。它的目的是确定和量化这种类型的挡土结构的抗震机制。重点放在评估系统的响应，包括一系列墙和锚的几何形状，同时考虑非弹性土壤的行为。研究了地震荷载作用下系统构件（即墙体、锚杆和土体）的相互作用效应。对各种部件对动态响应的贡献的更好理解正在纳入初步设计建议中。这些建议导致了合理考虑地震荷载影响的设计程序。

Tied-back (anchored) retaining walls formerly were used mostly to support temporary earth excavations. However the use of this type of wall construction for permanent structures has recently become more widespread, especially along highway interchanges and as shoreline structures. The advantages of this type of construction over the more conventional cantilever and gravity walls include lower cost for large wall heights (over 50 feet), and easier construction. However, there are at present no rationally-based design procedures in use for these walls that account for seismic loading. Due to the fact that tied-back walls have traditionally been used as temporary structures, very little research has been directed to the seismic design of such structures. This research project is an analytical investigation of the seismic response of flexible tied-back retaining walls. It is directed toward determining and quantifying the mechanisms of earthquake load resistance that develop for this type of retaining structure. Emphasis is being placed on evaluating the response of systems comprising a range of wall and anchor geometries, while accounting for inelastic soil behavior. The interaction effects of the system components (i.e. the wall, anchors, and soil) during seismic loading is being studied. The improved understanding of the contributions from various components to the dynamic response is being incorporated into preliminary design recommendations. These recommendations lead to a design procedure that accounts rationally for the effects of earthquake loading.