Open Engineering (Feb 2024)
Numerical and experimental comparison study of piled raft foundation
Abstract
The piled rafts are expressed as consisting of three geotechnical elements (piles, raft, and soil). As the load can be divided between the piles and the raft, the piles are highly effective in reducing settling and increasing the bearing capacity of the piled rafts, compared to shallow foundations. Civil engineering is witnessing a development in the field of geotechnical engineering, and because the experimental study takes a long time to verify, so the numerical study was conducted by the program MIDAS GTS NX 2020 (v1.1) for comparison with the experimental study. Small-scale models were tested in a sandbox placed in an iron structure containing a hydraulic jack with a capacity of 50 tons, and then, a vertical load was placed in the center of the raft; the bearing capacity was recorded by the load cell, the settlement was recorded by the dial gauge digital and the LVDT, in this study, the number of piles (9) was taken hollow aluminium, the diameter of piles (25) mm, and length of pile (500) mm. They were distributed under the raft by (3 × 3). The distance between the piles was taken by three-dimensional (3D) of the pile, and the dimensions of the raft were 250 mm × 250 mm, with a thickness of 20 mm. Numerical modelling was also used in the MIDAS GTS NX 2020(v1.1) program to solve the problem of the piled raft system for modelling and analysis. 3D models were analyzed using a sandy soil model with a raft of iron 250 mm × 250 mm and a thickness of 20 mm using piles of hollow aluminium with a length of 500 mm and a diameter of 25 mm and the number 3 × 3. As well as taking the criteria (Cullum-Mohr) and (von Mises). It was shown that the numerical study could be relied upon in the field of geotechnical engineering, where the percentages of convergence between the two studies were up to 91% in the piled raft test and 89% in the raft test only.
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