in order to mobilize shallow soil to participate in the interaction of piled raft foundation sufficiently, the concept of piled raft has been modified to new type of foundation named composite piled raft. in the system of composite piled raft, the short piles made of flexible materials is used to strengthen the shallow soft soil, while the long piles made of relatively rigid materials is used t...

Negative skin friction occurs when concrete piles are situated in soft soils, consolidating soilmass, etc., resulting in a downward force that increases loading on shaft piles and reduces the bearing capacity of the piles. A new concept based on the shifting rate of piles, and the settlement rate of the surrounding soils has been suggested far the study of negative skin friction. Negative skin ...

Most Codes such as API and BSI recommend Morison’s equation to estimate hydrodynamic forces on offshore structures. Significant differences exist among these Codes due to using different methods of analysis and estimation of force coefficients. In this paper, data from full scale tests have been used to evaluate random waves and uniform current actions on the smooth piles. Four time and ...

Energy piles-A fairly new renewable energy concept-Use a ground heat exchanger (GHE) in the foundation piles to supply heating and cooling loads to the supported building. Applying phase change materials (PCMs) to piles can help in maintaining a stable temperature within the piles and can then influence the axial load acting on the piles. In this study, two kinds of carbon-based composite PCMs ...

Discrete piles are used to stabilise infrastructure slopes, especially where there is insufficient additional land to allow construction of large toe berms or regrading of the slope. Compared with more conventional structures such as retaining walls, there are few field data on how discrete piles typically bend and displace under slope loading. This paper presents the results from monitoring a ...

in the realistic manner, piles are similar to the slender columns that soil around them acts as a lateral support. the piles situated in the liquefiable soil layers, loss their lateral supports due to the liquefaction resulted from the seismic ground motion. in this case, pile has the potency of axial instability similar to the unsupported columns. this instability can lead to the lateral buckl...

in present research, 17 centrifuge tests have been conducted to study the effect of various parameters such as the number of piles, the distance between piles, gradation and thickness of the granular layer on the load-settlement behavior of a pile raft system. the results showed the importance of granular layer to reduce the settlement of non-connected pile raft system when the roles of piles a...

The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most s...

We report experiments on piles of cohesionless granular materials showing the effect of construction history on static stress distributions. Stresses under piles are monitored by sensitive capacitive techniques. The piles are formed either by pouring granular material from a funnel with a small outlet (localized source), or from a large sieve (homogeneous rain). Localized sources yield stress p...

Alkaline copper quaternary (ACQ) is a widely used wood preservative. This study evaluated leachate volume generation and contaminant leaching from ACQ-treated lumber during rainfall events in comparison to untreated lumber. The influences of wood preservation with ACQ, lumber size, and weather on leachate generation ratio and contaminant concentrations in wood leachate were investigated with fo...