Effect of Dual Geotextile Reinforcements on Shallow Anchor Uplift Capacity

Small scale laboratory pullout model tests were performed on sand beds having a relative density (Rd) of 70% in the present study. For the tests, a mild steel test tank of 1000 mm (length) × 1000 mm (width) × 1000 mm (height) and circular-shaped anchor size (D) of 100 mm were used. The embedment depth (L) to diameter (D) ratio (L/D) of the anchor plate during the model tests was maintained constantly at 4. For the anchor uplift capacity improvement, the model tests were performed using polypropylene geotextile (PPGT) as a reinforcement material. Furthermore, a series of laboratory model tests were performed to see the effect of number of reinforcements on anchor uplift capacity using single and double number of reinforcements having a size of each 2D and maintained 0.1D and 0.5D vertical spacing (h) for the case of double number of reinforcements. For all the model tests, the first reinforcement was placed directly above the anchor plate. The test results showed that the improvement is higher with double reinforcements at lower uplift displacements compared to the single number of reinforcements. However, irrespective of number of reinforcements, the test results revealed that the amount of improvement of the anchor ultimate capacity is same.