NDM tunnelling for storm water under Corniche Road
NDM tunneling for storm water pipeline under Corniche road included micro-tunneling for DN 1800 mm ID, 56 m long storm water drainage tunnel. The tunnel was to be made 4 m below ground level under the busy Corniche Road. Thus, instrumentation monitoring was critical for safety of infrastructure and lives.
Consultants decided for continuous monitoring during tunneling, as it was being done in silty soil, just 4 m below a busy road. Monitoring plan included instrumentation around the driving and receiving pits of the micro-tunneling jacking machine. Instruments were also installed in the monitoring arrays across the tunnel alignment.
Encardio-rite’s sister concern Encardio-rite Geosystems LLC in UAE was awarded I&M sub-contract for the complete monitoring solutions that included
- Supply, installation and monitoring of geotechnical instruments that included inclinometer, piezometer, borehole extensometer, earth pressure cell and settlement points
- Drilling works
- Optical Surveying
- Daily & weekly reporting with evaluation & interpretation
Monitoring and surveying was scheduled at every 2 hours 24 x 7 during excavation and tunneling works. As the monitoring and surveying was being done on and around the busy road, it was scheduled precisely to meet the tunneling works; adhering to the permitted time frames from Authorities. The teams worked in shifts 24 x 7 to meet the challenging demands of the Project.