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In this research, a numerical study through three-dimensional finite element method is carried out to investigate the behaviours of pile foundations including piled raft and pile group subjected to...

Connected piled raft foundations (CPRFs) have proven to support heavy structures under vertical load. However, when subjected to seismic loading, significant load transfer from the raft beneath to ...

An empirical non-dimensional reduction factor has been developed in this paper using 192 laboratory model test results of the previous studies made by authors for a strip foundation supported by sand and subjected to eccentrically inclined load for both types of loading, i.e. line of load application inclined towards the centre line of the foundation (partially compensated case) and away from the centre line of the foundation (reinforced case). The reduction factor is the ratio of the ultimate inclined load per unit area of the foundation subjected to an eccentrically inclined load (i.e. partially compensated or reinforced loading) to the ultimate bearing capacity of the same foundation subjected to a centric vertical load at the same embedment ratio, Df/B. The developed reduction factor has been compared with those based on the earlier bearing capacity studies in this area available in the literature. The comparison seems to be reasonably good.

This technical note presents the results of a series of tests carried out on instrumented model pile-raft foundation to investigate the load sharing ratios between the foundation’s components where a loose sand layer is encountered near the ground surface. Four different pile-raft models with two different pile numbers and lengths were considered. In each model, the settlement of the raft and the load of each pile were monitored during the load application process. The experiments showed the effectiveness of pile length on reducing the overall settlement of the pile-raft system. The results showed also that the proportion of load transferred to any pile in a closely spaced pile group increases with its distance from the centre of the group. Unlike some previous studies that classified soil profiles containing loose sands near the surface as unfavourable situations for piled rafts, the experimental results herein represent an evidence of the efficiency of piled rafts even in soil profiles with loose sands ...

This paper introduces an attempt to examine the effect of batter angle of a single pile model on its ultimate vertical load capacity. A 32-steel solid pile models are used in this research. Three lengths of piles are selected (300, 400, and 500 mm) for embedment ratios (depth to width, L/D) = 15, 20 and 25, respectively. Batter pile is embedded in three different relative densities of sand (loose, medium and dense sand bed). The constant rate penetration test (CRPT) method was selected using a manufactured driving hammer to install the pile models in a steel box with dimensions 1000, 750 and 700 mm. The vertical load is conducted monotonically by a special hydraulic apparatus. The results indicate there is an optimum batter angle 20° that gave a higher load capacity. Pile load capacity is highly affected by relative density and less affected by L/D ratio.

Bearing capacity of shallow foundations is one of the most important areas of study in geotechnical engineering. Since the founding work of Terzaghi (1943), results of several theoretical and experimental investigations have been published. Most of these studies relate to the case where the foundation is subjected to centric vertical load. In the present paper, an attempt has been made to summarize the important developments related to the estimation of the ultimate bearing capacity of a shallow strip foundation on granular soil subjected to eccentrically inclined loading. Reduction factors to estimate the ultimate bearing capacity of foundations have been discussed.

Results of laboratory model tests to determine the ultimate bearing capacity of shallow strip foundation supported by sand and subjected to eccentrically inclined load are presented. The tests were conducted in dense and medium dense sands. The embedment ratio (ratio of the depth of embedment Df to the width of the foundation B) was varied from zero to one. The load eccentricity e was varied from zero to 0.15B as well as the load inclination from zero to 20 degrees. Based on the results of the present study, an empirical nondimensional reduction factor has been developed. This reduction factor is the ratio of the ultimate bearing capacity of the foundation subjected to an eccentrically inclined load to the ultimate bearing capacity of the foundation subjected to a centric vertical load.

A recent technique of pile installation of pre-cast piles without noise or vibration is the use of pile jetting. Water jets at high pressures are used to drive the piles that temporarily liquefy the soil thus allowing the pile to penetrate into the ground under their self-weight. This technique is utilized under conditions where control of construction induced vibration is essential, such as amidst existing structures within a city zone. Due to the excessive water velocity introduced in jetting, soil in the immediate neighbourhood is eroded thus creating a narrow water path along which eroded material is brought to the surface. This paper discusses the numerical modeling of the pile jetting process, the lateral extent of the spread of pore pressure zone around the jetted pile and the effect of pile jetting on the vertical load carrying capacity of adjacent piles. Finite element analyses were performed in two phases using ABAQUS. The results from the analyses clearly illustrate the extent of the so...