Rock Mass Quality for Tunnel Boring Machine (Q TBM)

[Update: This post is by Mr. Ramadoss Muthukuar, details here. He will also be contributing to this blog hereafter]


Rock Mass Quality for Tunnel Boring Machine (Q TBM)

I came across an article which is quite unique and interesting to study about Rock Mass Quality, so far wrt Rock Mass classification i have studied various quantitative approaches from RQD to GSI and these shall be applicable for both conventional and mechanized Tunneling methods.

But Sir Barton et al  approach for TBM is quite impressive, he modified his Rock Mass Quality (Q) of Conventional Tunnelling with Machine Rock parameter like Cutter life index,Quartz content in rock mass & average cutter load finally  arrived the  (Q TBM).By using this Rock mass quality index the penetration rate(PR) ,advance rate (AR) and necessary support requirements shall be designed.Even by advancing/varying the Penetration Rate (PR), advance rate (AR) and with other rock parameters the Rock Mass quality shall be back analyzed. 

I found this Rock Mass Quality (Q TBM) for Tunnel Boring Machines is logically represented and it will much helpful in designing the supporting system,tentatively to predict the time for boring tunnels with TBM and also to design the cutter head according to the requirement.

Link for download is shared in this blog:- 
http://tunnellingnatm.blogspot.com/2014/02/rock-mass-quality-for-tbm.html