Details of the Road Under Bridges (RUB) to be constructed along National Highway 275K (Mysuru Outer Ring Road)
To provide bottleneck free drive along the Outer Ring Road, NHAI-Bengaluru division has initiated civil works tender to widen the existing Road Under Bridges (RUB). Total cost of the project amounts to 85.13 crore INR.
Following existing RUBs are to be widened-
- Mysuru-Hassan Railway line at Metagalli

- Mysuru-RBI Railway line

- Mysuru-Bengaluru Main Railway line

- Mysuru-Nanjangud Railway line

Below is the typical cross section of the proposed RUB expansion. Expansion would be carried out using the Box pushing technique, wherein, a precast RC box segment is hydraulically pushed into the soil with a leading metal cutter head that aids in piercing into the soil thus advancing incrementally. And then subsequently more box segments are added one behind the other as the whole unit advances.
In this case, 3 such independent tunnel units would be launched i.e. one for the main carriageway and two such for the service lanes as seen below.
Typical Cross section of the RUB

Know more about Box Pushing Technique: Video
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