ارزیابی آزمایشگاهی عملکرد مهارهای تک و دو صفحه ای و مشاهده تاثیر فواصل بارگذاری در دیوار حائل

Retaining walls have many applications of geotechnical activities, the most important of which is the control of lateral soil pressure. There are several methods for restraining retaining walls, including mechanical restraints buried in the soil. Plate anchors are categorized as the no-grout mechanical anchors ith the capabilities such as withstanding foundation uplift, stabilizing wind turbine and marine platforms, and anchoring submerged and buoyant pipelines. In this paper, the performance of the retaining wall restrained by single-plate and double-plate restraint under constant strain loading, which includes the load-bearing capacity of the wall, horizontal displacement and the effect of loading heel distance to wall height, is investigated. The effect of the mentioned cases on the shape of the wedge rupture has been observed by particle image velocimetry (PIV) method. Taking into account the scale coefficient of 0.1 and applying static loading in plane strain conditions, the test chamber with dimensions of 120 cm in length, 50 cm in width and 80 cm in height has been modeled and constructed. One side of the chamber is covered with 2 cm thick Plexiglas to observe the performance of the wall against the test variables. The chamber is filled with poorly graded sandy soil (SP) of Sufyan region of East Azerbaijan province with a specific weight of 16.67 kN / m3 and an internal friction angle of 28 ° and a constant density in the form of dry precipitation. The mechanical loading system consists of a loading jack coupled with a digital display and a load cell with an accuracy of 0.1 g placed on the ground, which can be measured by rotating the loading shaft at each stage, the amount of force applied to the loading heel and also The opening of the jack is measured by a displacement gauge with an accuracy of 0.1 mm. Accordingly, the lowest horizontal displacement and the highest bearing capacity are related to the control of two plates with the same surface. The first step is without load and the first image is formed from the soil surface without deformation. This work was continued in a total of 7 steps until reaching a settlement of 35 mm of the loading heel, followed by shooting at the end of each loading stage. Accordingly, the lowest horizontal displacement and the highest bearing capacity are related to the double plate with the same surface. Decreasing the ratio of loading heel distance to wall height has shown more load-bearing capacity and less horizontal displacement in the wall. According to the analysis of PIV results, the particle strain at the critical slip surface is obtained in double plate inhibitions smaller than the single plate inhibition, and by reducing the ratio of loading heel distance (D) to wall height (H), the amount of soil particle strain has increased significantly (the performance of the retaining wall has weakened) and by increasing the ratio of loading heel distance to wall height, the effect of inhibitory plates in control Horizontal displacement and increased bearing capacity (retaining wall performance has been improved). In this regard, by reducing the ratio of loading heel distance to wall height, the restraint behavior of single and double plates has become more similar and their effect on wall performance has been observed with a slight difference in the strain of soil particles.