Research needs for new construction using trenchless technologies

This paper presents a considered view of research needs associated with new pipeline construction using trenchless techniques, such as pipe jacking, microtunnelling and horizontal directional drilling. These research needs were compiled by core members of NETTWORK prior to, and then debated at, a UK workshop involving those with specific interests in the topic from academia, industry and other stakeholders. The aims of the workshop were to assess whether the suggested needs were accurately stated, to determine whether there were any omissions and to attach a priority to the research needs. This was achieved by a process of debates and subsequent voting. For convenience, the issues have been categorised under the topic headings of generic issues, machine–ground interaction, pipes and joints, and associated works. In each case the important research studies that have been carried out, or were known to be in progress, have been highlighted so that research needs could be assessed in this context and references have been made to the most important documents arising out of the studies.The areas considered to be most important for research were: whole life costing of trenching and trenchless technology operations; issues associated with connections and laterals; mapping of underground infrastructure; multi-utility tunnels; drilling fluid reuse and disposal; improved modelling of ground movements; development of ‘see ahead’ technology; and the development of economic (remotely interrogated) sensors for pipes and joints. Work in many of these topics has since got underway.