Senthilnath G T

This paper presents a case study about the construction of a 6m x 8.5m cross sectioned and ~120m long Bukit Panjang Underpass. The project consists of a pipe roof box system that was constructed using 2.0m diameter steel pipes with steel frame supports. The various aspects associated with the large diameter pipe roofing system including the challenges encountered during construction have been discussed in this paper.

This paper presents simple implementation of absolute tunnel displacements visualisation in the ubiquitous spreadsheet software (eg. Microsoft Excel). A practical procedure for predicting and comparing displacement behind the face in relation to face advance and time is presented with a case study of mined tunnel in shallow overburden condition. The case study considers a mined tunnel which is in overburden ranging from 6m to 8m under a road with significant traffic as well as major utilities… Show more

This paper presents simple implementation of absolute tunnel displacements visualisation in the ubiquitous spreadsheet software (eg. Microsoft Excel). A practical procedure for predicting and comparing displacement behind the face in relation to face advance and time is presented with a case study of mined tunnel in shallow overburden condition. The case study considers a mined tunnel which is in overburden ranging from 6m to 8m under a road with significant traffic as well as major utilities and services. The design included temporary excavation support using staggered piperoof, sprayed concrete with lattice girder and wire mesh. Observations & insights provided by spatial visualization of the tunnel displacements are presented. Show less

Due to increased depth of tunneling, the time and cost involved in constructing
a deep shaft is very high. In order to minimize the number of shafts and to shorten the
construction period, it may be a viable option to drive TBM (Tunnel Boring Machine) from
either side (of stations/portals) so they could meet midway. The TBMs could be then docked
to establish a safe working chamber for concluding construction works including the TBM
dismantling, internal concrete lining etc.,… Show more

Due to increased depth of tunneling, the time and cost involved in constructing
a deep shaft is very high. In order to minimize the number of shafts and to shorten the
construction period, it may be a viable option to drive TBM (Tunnel Boring Machine) from
either side (of stations/portals) so they could meet midway. The TBMs could be then docked
to establish a safe working chamber for concluding construction works including the TBM
dismantling, internal concrete lining etc., without the need for any intermediate TBM retrieval shaft. This paper presents a case study of such TBM mid-tunnel docking performed in Singapore and also discusses details of structural design of temporary ground support system, analysis of settlement, assessment of potential impact on structures above the docking location and excavation sequencing. Show less

This paper presents a simplified implementation of probabilistic analysis for computing TBM operating face pressure in the usual design routine. This will allow to account for the uncertainty and variability of geotechnical parameters.

A comparison of pile load capacity predicted using the static load test and the high strain dynamic load test has been presented, a site specific and pile type specific correlation has been arrived.