Success and Failure in Predicting Pile Performance

This paper reviews the anatomy of predictions for pile and pile group performance, and discusses the various facets of the prediction process. A series of case histories is presented in which successful predictions were made of the pile performance. Most of these cases involve a single pile or a small group of piles. A further series of case histories is then discussed in which the predictions were far less successful. Most of these cases involve larger pile groups. The reasons for the success or otherwise of the predictions are discussed, and it is concluded that successful predictions require a combination of good ground characterization, a sound theory which reflects the mechanisms of behavior, appropriate selection of the necessary geotechnical parameters, and a good knowledge of the applied loadings, together with a measure of good fortune

Tall Building Foundation Design – the 151 Story Incheon Tower

The 151 storey super high-rise building is located in an area of reclaimed land constructed over soft marine clay in Songdo, Korea and is currently under design. This paper describes the design process in developing the foundation system of the supertall tower.The foundation design process described includes the initial stages of geotechnical site characterization using the results of investigation boreholes and geotechnical parameter selection, and a series of detailed two- and three-dimensional numerical analysis for the Tower foundation comprising 172 bored piles of varying length using finite element and boundary element methods. This paper will also provide a summary of the vertical and lateral pile load testing programs under both static and cyclic loading

Coastline changes in relation to longshore sediment transport and human impact, along the shoreline of Kato Achaia (NW Peloponnese, Greece)

Coastal configuration depends upon the equilibrium between available sediment budget and prevailing nearshore wave and current conditions. Human activities often disturb this natural equilibrium by altering the sources of beach material and littoral drift pattern. In the coastal zone of NW Peloponnese, an essentially tideless environment, the oblique approach of wind-induced waves implies an overall longshore drift from east to west. On an annual basis, the potential longshore sediment transport rates at the different sections of the study area (Kato Achaia) is estimated to vary between 0.02 10-3 m3/s and 5 103 m3/s and to fluctuate seasonally. The construction of a port and the extraction of aggregates from the R. Peiros have changed significantly the pattern of sediment transport inducing dramatic changes on coastline configuration; thus, the part of the coastline west to the port had retreated as much as 70 m eliminating a touristic beach, while the entrance of the port was silted inhibiting navigation. Coastal engineering measures, such as modification of port-breakwaters and construction of groins have had only minimal contribution in beach recovery. Hence, coastal management plans should consider this dynamic equilibrium and protect the natural coastal system from the arbitrary human activities

Foundation Design for the Burj Dubai – the World’s Tallest Building

This paper describes the foundation design process adopted for the Burj Dubai, the world’s tallest building. The foundation system is a piled raft, founded on deep deposits of carbonate soils and rocks. The paper will outline the geotechnical investigations undertaken, the field and laboratory testing programs, and the design process, and will discuss how various design issues, including cyclic degradation of skin friction due to wind loading, were addressed. The numerical computer analysis that was adopted for the original design together with the check/calibration analyses will be outlined, and then the alternative analysis employed for the peer review process will be described. The paper sets out how the various design issues were addressed, including ultimate capacity, overall stability under wind and seismic loadings, and the settlement and differential settlements. The comprehensive program of pile load testing that was undertaken, which included grouted and non-grouted piles to a maximum load of 64MN, will be presented and “Class A” predictions of the axial load-settlement behaviour will be compared with the measured behavior. The settlements of the towers observed during construction will be compared with those predicted