Tensile Behavior of Ground Anchors in Various Soil Compositions

Abstract

Due to the rapid growth of the human population, the availability of land suitable for construction is steadily diminishing. Consequently, the utilization of weak soils has become a necessity. When existing structures are in proximity to areas with weak soil conditions, the available soil must be effectively utilized. In such circumstances, particularly in the construction of high-rise buildings, anchor applications are implemented to enhance soil stability. Therefore, ground anchors serve a crucial function in reinforcing weak soils, ensuring the construction of safe and durable structures. This experimental study investigates the tensile behavior of ground anchors installed in a controlled soil mixture comprising 70% quartz sand and 30% bentonite clay. Laboratory-scale models were used to evaluate the performance of cement-based grouts with varying water-cement ratios (1:1, 1:1.5, and 1:2). The soil specimens were prepared in a model tank using five equal layers with consistent compaction energy, achieving unit weights ranging from 15.50 to 17.00 kN/m3. Pre-drilled holes were created using augers to predetermined depths for anchor installation. Following grout injection under constant pressure and adequate curing periods, tensile loading tests were conducted using a hydraulic jack at constant loading rates until failure. The experimental results demonstrate a significant inverse relationship between water-cement ratio and tensile strength, with lower water-cement ratios yielding substantially higher anchor capacities. These findings provide valuable insights for optimizing grout design in ground anchor applications for similar soil conditions.