Pile-supported foundations

Brown, A.A. Foundation Design for Pile Supported Tanks. Hydrocarbon Processing, September 1973, p. 175. Brown, A.A. A New Approach to Tank Foundation Design. Hydrocarbon Processing, October 1974, p. 153. 

In recent years, there have been a number of innovative piling systems in addition to the already established driven piles, drilled shafts and caisson foundations. A variant of the pile support system is the Augeo pile system. According to Abdullah et al. (2003), the Augeo pile system is theoretically cheaper than the conventional pile system. 

Brown, D. A. and Bollmann, H. T. 1992. Pile Supported Bridge Foundations Designed for Impact Loading , Transportation Research Record i33i, TRB, National Research Council, Washington, D.C., pp. 87-91. 

Anode supports, cable insulators and the coating on the object to be protected can be destroyed by anodic evolution of chlorine (see Section 7.1), Only chorine-resistant materials should be used. Anodes on retaining walls or between pile foundations can be installed in perforated or fabricated plastic tubes (half-shells) (see Fig. 16-8). They must naturally be provided with very many holes to avoid uneven removal of anode material. Filter tubes of a chlorine-resistant special material or... 

The layout of building foundation piles always depends on the building structure, geological condition and the type of foundation piles. It is not in regular lattice pattern in most cases. Many existing designing soft wares utilize so-called G-function and they cannot support the irregular layout. The author s... 

For high, heavy tanks, a foundation ring may be needed. Prestressed concrete tanks are sufficiently heavy to require foundation rings. Foundations must extend below the frost line. Some tanks that are not flat-bottomed may also be supported by soil if it is suitably graded and drained. When soil does not have adequate bearing strength, it may be excavated and backfilled with a suitable soil, or piles capped with a concrete mat may be required. 

The area of Taranaki surrounding Mt. Egmont is overlaid by volcanic ash which does not provide good bearing strength for equipment foundations. As a result all major foundtations are supported by piles, a total of approximately 7000 being installed. 

Foundations supported on piles should be constructed to allow the tops of the piles to extend about 6 inches into the base, with the bottom reinforcement about 2 inches above the piles. (See Figure 11-3.)... 

The type of foundation chosen will depend on the load to be supported and the bearing capacity of the soil, i.e., the unit loading or pressure. The intensity of pressure on the soil should ideally be uniform over the entire foundation. This is possible to achieve on hard rock, gravel, or good sand, and foundations of the footing or mat type are specified. In the case of compressible soils, such as mud, silt, or clay, differential settling occurs and -piling must be used. 

Piles. The need for sites adjacent to water-transportation facilities creates a problem of supporting structures on soft clay, silt, and mud of low-bearing capacity (see Table 8-1). Piles must be used as foundation supports in this case. 

After the failure of the Texas Tower TT-4, an important step forward was taken in the 1960s when oil drilling and related installations of pipelines at depths up to 60 m off the Mississippi Delta were begun. These installations were designed based on a more fundamental understanding of sediment properties. Oil platforms off the Mississippi Delta are of the jacket or template type which are supported by a long open-ended steel pipe pile foundation. 

Piles are used to transmit structural loadings to the subsoil when the surface sediments cannot support the load. They may be single or in groups, and may be fully or partially embedded. Recent advancement in installation equipment has allowed diese members to be driven in any desired environment and up to 460 m of water depth. The versatility of pile foundations has made them adaptable to most types of conditions and requirements. A detailed discussion of classical methods employed on land has been presented by Kezdi (1975). Methods employed offshore have been discussed by McClelland et al. (1967,1969), McClelland (1974), McQelland and Cox (1976), Randolph (1983), and Randolph and ( urvenec (2011). Methods and techniques applicable to the marine environment will be discussed in the following sections. 

As shown in Fig. 3. a horizontal combination shield and water tank assembly is generally indicated at 48 and extends entirely over the top of the pile and is supported on the foundation 39. This assembly is made up of a... 

Micropiles are smaller diameter piles mainly used in an underpinning operation when there are no other options to support buildings in use. A wide range of applications has also been documented which shows the versatihty of this technique. The piles can therefore function like an ordinary foundation pile as well as a compensation pile for remedial works especially in areas with site constraints. The design procedures for micropiles are no different than the conventional pile although various products have their own guidelines. 

To conduct a static load test, there must be a means of applying the desired loads to the foundation and measuring the resulting settlement. The most common method is the kentlegde system whereby dead weights such as precast concrete blocks are stacked on top of the foundation, as shown in Figure 11.1. An alternative is to provide multiple support in the form of reaction pile and use them as a reaction for a hydraulic jack (Figure 11.2). 

The design of a pile system for an embankment is similar in principle to the foundation design to support other structures. The pile foundation is needed under sections where settlements are to be kept to rninimum, such as adjacent to a road culvert, overhead bridge or bridge for a river crossing. In these cases, the piles are usually driven to set. 

Huat, B.B.K., Craig, W.H. Ali, F.H. 1994. The mechanics of piled embankment. FHWA International Conference on Design and Construction of Deep Foundations. Orlando. Florida, USA. 2 1069-1082. Reid, W.M. Buchanan, N.W. 1984. Bridge approach support piling. In piling and ground treatment. London Telford. 267-274. 

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