China
Africa
Explore chapters and articles related to this topic
Constructions and related matters relevant to environmental health
Published in Stephen Battersby, Clay's Handbook of Environmental Health, 2023
John Bryson, Stephen Battersby
A deep foundation is used to transfer a load from a structure through an upper weak layer of soil to a stronger deeper layer of soil. There are different types of deep foundations including helical piles, impact-driven (displacement) piles, drilled shafts or replacement piles (using an augur to extract soil and replacing it with reinforced concrete, and piers.
Deep foundations
Published in Jonathan Knappett, R. F. Craig, Craig’s Soil Mechanics, 2019
Jonathan Knappett, R. F. Craig
Whereas shallow foundations are wide compared to their depth, deep foundations are elements which are much smaller in plan but extend to greater depth within the ground. The most common type of deep foundation is the pile, which is a column of concrete, steel or timber installed within the ground (Figure 10.1). Piles may be circular or square in section, but will always have an (outside) diameter (D0) or width (Bp) that is very much smaller than their length (Lp), i.e. Lp >> D0. A pier or caisson is another type of deep foundation which comparatively has a larger diameter compared to its length, i.e. Lp > D0, but which can be analysed in the same way as a pile. Caissons are often used as foundations for offshore structures or the piers of large bridges crossing water.
Foundations
Published in Alan J. Lutenegger, Soils and Geotechnology in Construction, 2019
The most common type of drilled deep foundation is usually referred to as a drilled shaft. Other terms, including “drilled pier” or “caisson,” have also been used to describe this type of foundation. Drilled shafts are also sometimes referred to as “cast-in-drilled-hole (CIDH) piles.” They have been used since the late 1930s, when the first truck-mounted auger drill was fabricated to drill shafts for the support of some bridges in the U.S. In the early 1900s, hand-dug shafts were used in stiff clays in Chicago, Boston, and New York to support early high-rise structures.
Dynamic behavior of pile foundations under vertical and lateral vibrations: review of existing codes and manuals
Published in HBRC Journal, 2020
Mohamed M. Khalil, Asmaa M. Hassan, Hussein H. Elmamlouk
The design of foundations under dynamic loads is complex and should involve structural, mechanical, geotechnical engineering in addition to the theory of vibration. The geotechnical engineer decides to support a structure on a shallow or deep foundation system based on many factors including the subsurface conditions and the induced dynamic and static loads. In case of using a deep foundation system, the design requires a full understanding of the dynamic interaction between the piles and the soil (pile-soil interaction) and between adjacent piles (pile-soil-pile interaction).
Design of Shallow and Deep Foundations, 1st Edition
Published in International Journal of Geotechnical Engineering, 2023
The design of deep foundation is much more complex compared to shallow foundation. Consequently, this chapter delves into the complexities associated with negative skin friction, lateral loading, and the impact of pile groups on design. Moreover, the authors took additional step to explore the design of barrettes and foundation elements that are relatively close to the surface, yet still necessitate consideration of skin friction. In the final section for deep foundation, the authors discussed the construction provisions, selection of pile types, and inspection of piles.
Monitoring analysis of influence of extra-large complex deep foundation pit on adjacent environment: a case study of Zhengzhou City, China
Published in Geomatics, Natural Hazards and Risk, 2020
Danqing Song, Zhuo Chen, Lihu Dong, Gaojie Tang, Kelu Zhang, Heng Wang
At present, many scholars have obtained research results on deep foundation pit excavation technology and its effect on the surrounding environment (Wang et al. 2014; Zhang, Xie, et al. 2015; Wang et al. 2016). Wang et al. (2018) used the model test method to study the local expansion phenomenon of stratified settlement in the process of foundation pit dewatering and used numerical simulation based on the finite difference method to verify this phenomenon. Zhu et al. (2015) established a three-dimensional dynamic numerical model considering the vibration load of a subway train and studied the influence of train vibration on deep foundation pits and permanent support structures. In soft soil areas, the environmental effect of deep foundation pits is becoming increasingly serious; in particular, large-scale earthwork excavation unloading and the long-term accumulation of confined water due to precipitation will cause large variations in the displacement field and stress field of not only the surrounding soils but also the surrounding strata with a large compressibility, low strength and high sensitivity, which are more likely to cause (uneven) settlement of the surrounding buildings, pipelines and surrounding roads and even cracking destruction (Zhou et al. 2010; Wang et al. 2014, 2016). Zhang, Zhang, et al. (2015) investigated the influence of foundation pit excavation on the settlement of the surrounding strata and underground diaphragm walls and the structural deformation of buildings by using field monitoring methods. Kang et al. (2016) systematically studied the influence of the maximum lateral displacement depth of a foundation pit retaining structure on the uneven settlement of adjacent pile foundation buildings and the displacement field of a deep soil layer around the pit based on the analysis of measured engineering data and finite element numerical simulation. Therefore, because the effects of foundation pit deformation on its surrounding soil and buildings are very complex during excavation, the deformation characteristics of its adjacent buildings should be considered.