This paper presents the results of 1g model tests performed on instrumented model foundations, i.e., unpiled raft, single piled raft, single disconnected piled raft (DPR) and 3 × 3 DPR in sand under vertical load by using different granular materials and thickness of the granular cushion layer to investigate the effects of granular cushion on the performance of DPR system. The Settlement Efficiency (η) of the DPR which is nonlinear in nature is found to increase as the cushion thickness decreases and the mean particle size (d₅₀) of the cushion material increases. A cushion thickness of two times the pile diameter and cushion material having d₅₀ more than or, equals to 2 mm might serve as the suitable cushion material for the optimum performance of 3 × 3 DPR. The neutral axis and the zone of occurrence of maximum axial load of the pile in DPR are found to move downward with increasing cushion thickness. The piles in DPR are found to carry 35% of the total superstructure load within the settlement range considered in the study.

本文介绍了在使用不同的颗粒材料和不同厚度的情况下，在垂直荷载下，在无桩筏，单桩筏，单桩筏，单断开桩筏（DPR）和3×3 DPR的仪器模型基础上进行的1 g模型试验的结果。颗粒垫层，以研究颗粒垫对DPR系统性能的影响。已经发现，本质上是非线性的DPR的沉降效率（η）随着垫层厚度的减小和垫层材料的平均粒径（d ₅₀）的增加而增加。垫层厚度是桩直径的两倍，垫层材料的d ₅₀大于或等于2毫米可能用作3×3 DPR最佳性能的合适缓冲材料。发现DPR中桩的中性轴和最大轴向载荷发生区域随着垫层厚度的增加而向下移动。在研究中考虑的沉降范围内，发现DPR中的桩承载了总上部结构荷载的35％。