Investigation on the geological and geotechnical factors leading to a major slope failure at a selected site on a Jordanian highway

During and after the very wet 1991/1992 winter experienced in Jordan, significant slope failures occurred along several sections of the new Irbid-Amman highway in Jordan. The topography over most of the route is hilly, and significant amounts of cut and fill were used to construct the highway. One such slope failure lies at 44+800 km on the highway south of Jerash City at a distance of about 5.0 km from Wadi Zerqa bridge. A landslide occurred downslope of the highway embankment resulting in a collapse of the most of the gabbion wall supporting the embankment. This paper deals with the overall stability of the slope at 44+800 km. It presents the geological and geotechnical studies carried out at this site, identifies the causes and mechanism of instability, and presents appropriate remedial measures. The study concluded that the landslide movement occurred within the colluvium material. It resulted primarily from excess piezometric pressures generated within the slope as a direct consequence of inadequate drainage. It is recommended to reconstruct the entire gabbion wall with its foundation seated on the sandstone that underlies the colluvium and to install a surface drainage system at the site.     

浙江上虞—三门高速公路K270＋700边坡变形破坏分析及治理

浙江上虞—三门高速公路是连接浙东南沿海经济圈与浙中部地区的重要交通枢纽,2011年10月26日,该高速公路管理处养护人员发现桩号K270＋700处边坡有明显变形现象。本文在现场调查分析的基础上对上三高速公路K270＋700边坡进行了系统研究,研究分析表明,该边坡的破坏模式为两组控制性结构面相切产生的楔形块体沿交线方向发生滑移破坏。最后,针对边坡的破坏模式和现状情况提出应急抢险和永久性治理相结合的综合治理措施。     

A macroscopic damage‐plastic constitutive law for modeling quasi‐brittle fracture and ductile behavior of concrete

A new phenomenological macroscopic constitutive model for the numerical simulation of quasi‐brittle fracture and ductile concrete behavior, under general triaxial stress conditions, is presented. The model is particularly addressed to simulate a wide range of confinement stress states, as also, to capture the strong influence of the mean stress value in the concrete failure mechanisms. The model is based on a two‐surface damage‐plastic formulation. The mechanical behavior in different domains of the stress space is separately described by means of a quasi‐brittle or ductile material response:

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