Paper 2-A-04 - 1 ______________________________________________________ Paper 2-A-04 MICROTUNNELLING – RECENT EXPERIENCE IN IRELAND Ciaran Reilly 1 and Trevor Orr 1 1 Dept. of Civil, Structural & Environmental Engineering, University of Dublin, Trinity College, Dublin, Ireland ABSTRACT: This paper presents case studies from several microtunnelling projects carried out for sewer improvement schemes in Ireland over the past two years. Ireland’s soils present challenging geotechnical conditions for microtunnelling, while the Irish microtunnelling and pipejacking industry is still relatively young and experience is limited. Jacking forces for two schemes are analysed and it is shown that jacking forces are largely controllable with correct application of modern pipejacking lubrication systems. Observed settlement trough parameters during tunnelling in Irish glacial tills are reported and the results of some vibration measurements are discussed. It is hoped that this information will be of use to those considering the use of microtunnelling in Ireland in future, as the industry is set for growth. 1. INTRODUCTION Although still at a relatively early stage, the microtunnelling and pipejacking industry is growing apace in Ireland. Local experience is developing rapidly as local contractors are getting exposure to the technologies and clients are seeing the benefits of less invasive methods for laying pipelines in dense urban areas, sensitive environments,