Pipe jacking, microtunneling, and pipe ramming are common trenchless techniques for installing pipelines or cables below the bed
of watercourses. A tunnel boring machine (TBM) is also used for constructing pipelines with large diameters or tunnels underneath the bed of
watercourses. Most pipeline and tunnel installation methods used for river crossings induce strong vibrations during construction and should
be monitored to ensure pipeline integrity, canal bed stability, and steady flow characteristics. In this study, the effect of vibrations of a buried
pipeline on canal bed morphology is experimentally explored. A total of 135 tests were conducted using different canal flow depths, Froude
numbers, pipeline diameters, pipeline depths under the canal bed, and vibration amplitudes. Empirical formulas were deduced to estimate the
canal bed deformation due to the vibrating buried pipeline. Results reveal that for the considered parameters, the burial depth of 2.4 times the
pipe diameter reduced the deformed scour depth by up to 53%. The combined effect of flowing water in the canal and the pipe vibration
causes undesirable change in the canal bed; therefore, using TBMs or pipe jacking in case of a dry canal whenever possible could be better. |
