Two parallel road tunnels are being constructed for 6 lanes in the basalts. The tun-nels are D-shaped with diameter (B) of around 16 m and 2 m high side walls with clearspacing of 20 m. The maximum overburden (H) is 165 m. The rock mass parameters are,RMR = 73, Q = 10, Ja=1.0, Jr = 3.0 and Jw = 1.0 (minor seepage from side walls). Theconstruction engineers want rapid rate of tunnelling and life of support system should be100 years. The uniaxial compressive strength of SFRS is 30 MPa and its flexural strengthis 3.7 MPa.

Step 1: Determination of Rock Bolt Length The rock bolt length (L) can be determined using the…

wo parallel road tunnels are being constructed for 6 lanes in the basalts. The are D-shaped with diameter (B) of around 16 m and 2 m high side walls with ing of 20 m. The maximum overburden (H) is 165 m. The rock mass parameters R=73, Q = 10, Ja = 1.0, Jr = 3.0 and Jw = 1.0 (minor seepage from side walls). truction engineers want rapid rate of tunnelling and life of support system shoul years. The uniaxial compressive strength of SFRS is 30 MPa and its flexural stre 7140

wo parallel road tunnels are being constructed for 6 lanes in the basalts. The are D-shaped with diameter (B) of around 16 m and 2 m high side walls with ing of 20 m. The maximum overburden (H) is 165 m. The rock mass parameters R=73, Q = 10, Ja = 1.0, Jr = 3.0 and Jw = 1.0 (minor seepage from side walls). truction engineers want rapid rate of tunnelling and life of support system shoul years. The uniaxial compressive strength of SFRS is 30 MPa and its flexural stre 7140

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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