Over the years, ongoing developments in steel grades, section shapes and driving techniques have led to a wide range of applications for sheet piling. The applications include securing excavations, waterfront structures, foundations, bridge abutments, noise abatement walls, highway structures, cuttings, landfill and contaminated ground enclosures, and flood protection schemes.
The main engineering advantages of sheet pile walls over other types of wall are:
• the extremely favourable ratio of steel cross-section to moment of resistance,
• their suitability for almost all soil types,
• their suitability for use in water,
• the fast progress on site,
• the ability to carry loads immediately,
• the option of extracting and reusing the sections,
• their easy combination with other rolled sections,
• the option of staggered embedment depths,
• the low water permeability, if necessary using sealed interlocks, and
• there is no need for excavations.
Thanks to the aforementioned engineering advantages, plus their functionality, variability and economy, sheet pile walls have become widely acknowledged and frequently used components in civil and structural engineering projects worldwide.
Chapter 2 provides an overview of the most common sections and interlocks. Detailed information about the HSP sections available can be found in the Sheet Piling Handbook published by ThyssenKrupp GfT Bautechnik. This chapter also includes information on the relevant steel properties, the stress-strain behaviour, steel grade designations, suitability for welding and corrosion. The main driving techniques with their advantages and disadvantages are outlined, and publications containing further information are mentioned.
Chapter 3 describes briefly the field and laboratory investigations required when considering the use of sheet piling and includes the characteristic soil parameters from EAU 2004 as a guide. Of course, the publications referred to plus the valid standards and directives must be taken into account. Geotechnics must always take account of the effects of water. Chapter 4 therefore explains the basics of water flows, hydrostatic and hydrodynamic pressures, and hydraulic ground failure.
Chapter 5 deals with earth pressure. Reference is made to the classic earth pressure theory of Coulomb, the calculation of earth pressures according to current recommendations and standards, the consideration of special boundary conditions and earth pressure redistribution. Earth pressure calculations are explained by means of examples.
Chapter 6 first outlines the safety concept according to DIN 1054:2005-01 and EAU 2004, which is based on the partial safety factor concept of Eurocode 7. The special feature in the calculation of sheet pile walls is that the earth pressure can act as both action and resistance. First of all, the engineer chooses the structural system for the sheet pile wall, e.g. sheet pile wall with one row of anchors, fixed in the ground. The required length of the sheet piles, the anchor forces and the actions on the cross-section necessary for the design are then determined from the equilibrium and support conditions. The calculation and design procedure are explained by means of simple examples.
Chapter 7 provides an overview of current types of anchors, e.g. anchor piles, grouted anchors, tie rods and retractable raking piles. The most important methods of analysis are explained using two examples. DIN 1054:2005-01 also requires a serviceability analysis (limit state LS 2). The principal options here are the method using the modulus of subgrade reaction (please refer to the Recommendations of the Committee for Excavations, EAB 2006), and the Finite Element Method (FEM). The latter has in the meantime become firmly established in practice thanks to the availability of ever-better computer programs. The experiences gained with FEM and recommendations for its use in the design of retaining wall structures can be found in chapter 8. An example explains the principal steps entailed in the modelling work and the interpretation of the results.
Chapter 9 deals with dolphins. The choice of section depends not only on the design, but also on the transport and the method of driving the section into the subsoil, the corrosion requirements and, possibly, multiple use considerations. Chapter 10 provides helpful information in this respect. All that remains to be said at this point is that this sheet piling manual can offer only a brief, incomplete insight into the current state of the art regarding the engineering, design and construction of sheet pile walls. No claim is made with respect to correctness and completeness; ThyssenKrupp GfT Bautechnik will be pleased to receive notification of any omissions and corrections.