The 8th and latest edition of the piling handbook has a number of significant changes, says David Rowbottom.
The eighth edition of the Piling Handbook has been published by Arcelor RPS, the sales and marketing wing of steel sheet pile manufacturer Profi larbed.
It contains many changes from the seventh edition, published in 1997 by British Steel (latterly Corus), but the most fundamental one is that it has been produced by the piling engineers at Arcelor RPS.
Following the withdrawal of Corus from the manufacture of sheet piling, the chapter on products now contains details of the full range of Arcelor piles, from the lightest cold formed sections, through standard hot rolled piling, to the high modulus HZ/AZ system.
It lists the wide range of box piles available, fabricated from pairs of Z piles as well as U piles joined in twos, threes and fours. Details of the Corus piles available up to the cessation of manufacturing are given at the back of the handbook for the benefi t of anyone trying to identify and check the suitability of existing sheet pile structures.
Users familiar with the previous handbook will fi nd the chapter on installation is three times bigger, refl cting the importance of this topic. These extra pages allow new sections covering installation by leader rig and pressing techniques to be included, and the various pile driving techniques are described in greater detail.
A more scientific method has been developed to determine the size of pile required for impact driving, based on an assessment of the anticipated driving resistance and the input energy from the proposed hammer.
This method has replaced the old 'rule of thumb' or empirical method that related the strength or density of the ground directly to the section modulus but did not differentiate between different pile lengths. There is also more information to help in selection of a suitable vibratory pile driver.
Following on from installation is a new chapter providing useful information on the effects and extent of noise and vibration caused by pile installation, and methods by which it can be mitigated.
Piling should no longer be automatically thought of as an environmentally disruptive activity, and this chapter contains details of technology that can signifi cantly reduce any potential disturbance.
From a designer's perspective, the core of the Piling Handbook has always been the chapters on the derivation of earth and water pressure and those covering the design of sheet pile structures, including various worked examples.
These chapters have been extensively revised. The net pressure method, traditionally known as the Piling Handbook method, which has been included from the earliest versions published by Dorman Long and the Frodingham Iron and Steel Company, has been replaced to reflect changes in the codes and standards for piling design.
This edition adopts the factor on strength method of analysis as outlined in the recently published Ciria Report C580 and the worked examples illustrate how it can be applied to hand calculations.
Since the factor on strength method is effectively an ultimate limit state (ULS) approach, the load tables for walings and props have been changed to give ULS values.
Another feature of this edition is a chapter on the use of sealants to provide watertight construction for basements and containment barriers. Sealant systems are capable of producing basements in line with the requirements of BS8102: 1990 Protection of structures against water from the ground, but where a very high water tightness specification is to be achieved, a welded solution may be the best option.
This chapter contains descriptions of the various sealant types available and suggests methods of seal welding for a variety of conditions.
A review of the chapter on durability has led to some changes in the recommended corrosion rates.
The rates in the eighth edition are taken from the proposed Eurocode 3: Design of steel structures, Part 5: Piling document and, where appropriate, take into account the reduction in rate of thickness loss experienced in long term corrosion situations.
Coating systems to extend the life of piled structures in a variety of exposure conditions are described.
The references to coating systems PC1, PC2 etc - terms which will be very familiar to many piling engineers - were specifi c to Corus (British Steel) and consequently are no longer applicable.
Other minor changes include dropping the chapter on sample specifi ations as it was felt this information is readily available elsewhere - for example, the Model Specifi cation published by the Institution of Civil Engineers.
David Rowbottom is technical and marketing manager for Arcelor RPS UK.
The Piling Handbook (8th edition) is available from Arcelor RPS UK, tel: 0870 770 8057; email: arpsuk@arcelor.
com; www. sheet-piling. arcelor. com