Deep foundations

The archaeological period chosen for investigation was the Persian period, which has received only scant attention. This is partly because of the relative scarcity of archaeological remains, perhaps a consequence of the Assyrian and Babylonian conquests of the land and deportation of important segments of the population. Where Persian remains exist, they have often been partly destroyed by the deep foundations for massive stone architecture erected in the following Hellenistic period (third to first century B.C.). 

List the steps in sequence for construction of a slurry wall to permit a deep foundation near a river to be built in the dry. 

The holding capacity equation for an anchor is similar to the bearing capacity equation for a deep foundation. The general uplift capacity, f, of an anchor is often expressed as the following ... 

Kolk, H.Y (2000), Deep foundations in calcareous sediments. Proceedings of the International Conference Engineering for Calcareous Sediments, ed. K.A. Al-Shakei, Balkema, 2, pp. 313-344. 

Vesic, A. S. (1965), Ultimate loads and settlement of deep foundations in sand. Proceedings of the Symposium on Bearing Capacity and Settlement of Foundations, Duke University, Durham, NC, pp. 53-68. 

Vesic, A. S. (1967), A Study of Bearing Capacity of Deep Foundations, Final Report Project B-189, Georgia Institute of Technology, Engineering Experiment Station, Atlanta, GA. pp. 231-236. 

Suitable These are areas underlain by shallow estuarine/deltaic deposits (clay, silt with lesser amounts of sand and gravel and variable organic matter) and riverine deposits (sand, silt and clay with minor to moderate plant remains) of less than 5 m sand. Shallow peat (less than 1 m) normally occurs as narrow belts. These areas have a moderately deep foundation level or rockline (10 to 15 m) with minor to moderate amounts of subsidence expected and fair amount of fill required. 

Less suitable These are areas underlain by estuarine/deltaie deposits of more than 5 m thiek. They are below flood/tidal level and have a deep foundation level or roekline (15 to 30 m) that require a moderate amount of fill. 

The driven pile is the oldest and most widely used deep foundation system. Piles are normally columns made of wood, concrete, steel or plastic. They could also be composites such as concrete-filled steel pipe or plastic-steel composite, which are driven into the ground. 

Horvath, R.G. Kenney, T.C. (1979). Shall resistance and rock-socketed drilled piers. Symposium on Deep Foundations. A CE 182-214. 

A precise way to determine the ultimate axial (as well as pull out) of deep foundations is to build a full-size prototype foundation at the site of the proposed foundation and slowly load it to failure. This method is known as static load test. Static load tests are generally much more expensive and time-consuming, and thus must be used judiciously. 

Another dynamic method of evaluating the static load capacity of deep foundations is to install instruments on the foundation and use them to monitor load and settlement data obtained while the foundation is subjected to a dynamic impact load. This measured response to dynamic loads can then be used to develop design static load capacities. 

The most common source of dynamic loading is a pile hammer, because it is already on site and thus represents little or no additional cost. Therefore, these tests are most commonly performed on driven pile foundations. However, dynamic loads also can be obtained with drop hammers that enable testing of drilled shafts and other types of deep foundations. 

Hannigan, P.J. 1990. Dynamic monitoring and analysis of pile foundation installations. Deep Foundations Institute, Sparta, NJ. 

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. 

Almost all structures constructed on earth will transmit their load to the earth through their foundation. In other words, foundation is the lowest part of a structure, which is in contact with the soil and transmits the load of the structure to the ground. Therefore the design of the foundation is very important to ensure the stability of the structure it supports. Foundations are generally divided into two categories - shallow foundation and deep foundation. 

A shallow foundation is foundation built near or at ground (soil) or rock surface. This foundation is placed on firm soil near the ground and beneath the lowest part of the superstructure. Examples of these foundations are pad footing and spread footing. Deep foundation on the other hand is foundation that transmits structural loads to deeper soils or rock layers that are far from the surface. This foundation is constructed on a soil that is not firm, and transmits the load of the structure considerably below the ground of the lowest part of the superstructure. Deep foundations can be divided into two categories, that is pile foundation and drilled pier foundation or caisson. Piles are normally columns made of concrete, wood, plastic or steel that are driven into the ground. Drilled pier or caisson on the other hand is a special pile made of cast in situ concrete inside a bored or drilled hole. 

Steel strutted retaining structure is one of the common forms widely used in construction in deep foundation pit because of its convenient installation and disassembly. Lots of economic benefits are linked with the reuse of steel struts. Since steel strut can work immediately to effectively reduce the displacement of excavation after installation, priority could be given to the use of this form of supporting in case of buildings adjacent around the foundation pit or small deformation of the pit required (Bin, 2012 Wang, 1998). 

Figure 1. Three risk dimensions logical diagram of deep foundation pit engineering. 

Quality risk accidents, safety risk accidents and investment risk accidents of deep foundation pit are not independent from each other, when consider one kind of risk accidents and its factors separately we may leave out some inner relation of them and then get a distorted risk recognition result. Via combing accident cases of deep foundation pit, the article carried out an analysis on the relationship among quality risk, security risk and investment risk and then established a macroscopic logic diagram of the influence rule of the three objective dimensions, reached a tentative conclusion as follows ... 

This thesis aims at offering a reference for overall risk management of deep foundation pit construction, in addition, collecting basic data for risk theoretical analysis and study. Furthermore it is more important to learn a lesson from failure cases and accumulate experience in order to provide reference for the subsequent deep foundation pit construction. 

Chen Zhong-han. Deep Foundation Pit Engineering [M], Beijing China Machine Press, 2002. 

Tang Ye-qing. Analysis and Treatment of an Accident in a Deep Foundation Construction [M]. Beijing China Architecture Building Press, 1999. 

Yang Li-jun, Zhou Wei-dong. Common Problems and Treatment Measures of Deep Foundation Pit Engineering [J], Western Exploration Engineering. 2003,15(8) 58-59. 

Degree 4 Winds from 320 to 410 km h . Destruction of masonry buildings without deep foundations, light... 

Concrete slabs prevent that a pipeline is hit during digging activities. The effectiveness of concrete slabs and warning tapes is derived from experiments. In about 50 tests excavators were asked to excavate a deep foundation on sites were actually pipelines with concrete slabs were buried. They were not irfformed the pipeline was present at that site. By determining the reaction of the excavator the factors as given in Table 1 could be derived (Corder 1995). 

Figure 3. Triple cell peanut deep foundation of the Sail Marina Bay, Singapore.

Virollet, B. et al. 2006. Recent advances in Large Diameter Diaphragm Wall Shafts. Proceedings of the 31st Annual Conference on Deep Foundations. USA Washington, DC. 

Middle Middle Pile and deep foundations, water depression, complex of underground stmctures, changes of ground massif elastic state, natural-technogenic mode of ground water 25/40... 

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