1 Press-in piling: Ground vibration and noise during pile installation David White*, Tim Finlay**, Malcolm Bolton*** and Grant Bearss**** * Research Fellow, Cambridge University Engineering Department, Trumpington Street, Cambridge, CB2 1PZ, UK. e-mail: djw29@eng.cam.ac.uk ** MEng student, Address as above, e-mail: tcrf2@eng.cam.ac.uk *** Professor of Soil Mechanics, Address as above, e-mail: mdb@eng.cam.ac.uk **** Vice-President of Operations, Giken America Corporation, 5802 Hoffner Avenue, #707, Orlando, Florida 32822, U.S.A. e-mail: gbearss@gikenamerica.com Abstract Conventional dynamic piling methods are ill-suited to the urban environment. The press- in method offers an alternative technique of pile installation, which allows pre-formed piles to be installed with minimal noise and vibration. Field measurements of noise and ground vibrations during press-in piling are presented and compared to existing recommended limits. Based on this initial database, tentative prediction curves are presented. Equipped with these tools, designers can assess the relative environmental impact of each installation method when planning piling works. Introduction Pile driving is an activity that is ill-suited to the urban environment. The noise and ground vibrations created during the installation of pre-formed piles by dynamic methods can lead to human disturbance and structural damage. Stringent regulations now virtually preclude the installation of steel tubular piles by dynamic methods in urban Europe, and bored cast-in-place piles have become the most common design solution. Steel tubular piles offer a number of advantages over bored piles, particularly relating to issues of sustainability (Table 1). The embodied energy of a pile is the sum of the energy required to extract the raw materials, carry out any manufacturing or construction processes, and transport the material between and within these processes. A steel pile contains less embodied energy than a concrete pile of similar capacity. This advantage can be extended if the pile is extracted and re-used. Chapman et al. (2001) report that many sites in the City of London already contain multiple sets of old deteriorating bored piles, with little remaining space for future new foundations. Re- use of the pre-existing layout of bored piles is inconvenient, extraction is virtually impossible, and the construction of fresh piles is unsustainable. Historically, the noise and vibration pollution created by conventional pile driving methods has prevented the advantages of steel piles being realised. However, a novel technique for installing large tubular steel piles without noise and vibration has recently been developed. The technique of press-in piling makes use of hydraulic rams to provide the force necessary to jack pre-formed piles into the ground. The hydraulic rams form part of a robotic machine that uses previously installed piles to provide a reaction Proceedings of the International Deep Foundations Congress. Orlando, USA. ASCE Special Publication 116 pp363-371