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MODERN TRENDS IN TUNNELS

FOR HYDRO POWER PROJECTS

Presented By

P.K. SOOD

Executive Director

Dr. Hutarew & Partner (I) Pvt. Ltd.

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TYPICAL DETAILS OF HORSE SHOE TUNNEL

PORTAL

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TYPICAL DETAILS FOR HORSE SHOE

TUNNEL THROUGH SOUND ROCK

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TYPICAL DETAILS FOR HORSE SHOE

TUNNELS THROUGH FAIR ROCK

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TYPICAL DETAILS FOR HORSE SHOE TUNNEL

THROUGH HIGHLY JOINTED ROCK

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TYPICAL DETAILS FOR HORSE SHOE TUNNEL

THROUGH MODERATELY JOINTED ROCK

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TYPICAL DETAILS OF HORSE SHOE

TUNNEL THROUGH POOR ROCK

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BACK FILL GROUTING DETAILS FOR

HORSE SHOE TUNNELS

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TYPICAL DETAILS OF CIRCULAR TUNNEL

THROUGH SOUND ROCK

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TYPICAL DETAILS FOR CIRCULAR TUNNEL

THROUGH HIGHLY JOINTED / POOR ROCK

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TYPICAL DETAILS OF CIRCULAR TUNNEL

THROUGH MODERATELY JOINTED ROCK

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TYPICAL D-SHAPED TUNNEL

CROSS SECTION

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TYPICAL DETAILS FOR D-SHAPED TUNNEL

THROUGH MODERATELY JOINTED ROCK

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TYPICAL DETAILS FOR D-SHAPED TUNNEL

THROUGH HIGHLY JOINTED ROCK

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LONGITUDINAL SECTION OF D-SHAPED

TUNNEL

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TYPICAL DETAILS OF STEEL RIBS WITH

TIMBER BLOCKING

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LONGITUDINAL SECTION AT TRANSITION

FROM D-SHAPE TO CIRCULAR TUNNEL

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GENERAL LAYOUT PLAN SHOWING

TRANSITION DETAILS

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FIRST SECTION AT TRANSITION FROM D-SHAPE

TO CIRCULAR TUNNEL

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SECOND STAGE SECTIONAL DETAILS AT

TRANSITION (D-SHAPE TO CIRCULAR)

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THIRD STAGE SECTIONAL DETAILS AT

TRANSITION (D-SHAPE TO CIRCULAR)

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FOURTH STAGE SECTIONAL DETAILS AT

TRANSITION (D-SHAPE TO CIRCULAR)

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FIFTH STAGE SECTIONAL DETAILS AT

TRANSITION (D-SHAPE TO CIRCULAR)

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FINAL STAGE SECTIONAL DETAILS AT

TRANSITION (D-SHAPE TO CIRCULAR)

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TYPICAL DETAILS OF ROCK BOLTS

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TYPICAL DETAILS OF ROCK BOLTS WITH

100 MM THICK SHOTCRETE

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TYPICAL DETAILS OF ROCK BOLTS WITH

50 MM THICK SHOTCRETE

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TYPICAL DETAILS FOR STEEL SUPPORTS

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TYPICAL DETAILS OF SUPPORT JOINTS

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THANK YOU !!!

UNDERGROUND POWER

STATIONS

SOME GEOTECHNICAL

PROBLEMS ENCOUNTERED

PRESENTED BY:

P. K. SOOD

EXECUTIVE DIRECTOR

DR. HUTAREW & PARTNER (INDIA) PVT. LTD.

CONTENTS

• CHUKHA H. E. PROJECT (Bhutan)

• SANJAY H. E. PROJECT

(Himachal Pradesh)

• KADAMPARAI PUMP STORAGE

SCHEME (Tamil Nadu)

CONCLUSIONS • In view of the presence of various joints,

foliation, shear and thrust zones, seepage wateretc., the formation of unstable wedges whichcould drop down from the roof or side walls ofthe underground caverns, cannot be ruled out oravoided altogether. As much geologicalinformation as possible should be obtainedbeforehand and possibility of formation of allwedge mechanisms must be carefully examined.A well designed system of rock supportconsisting of rock bolts and shotcrete should beprovided. To avoid the possibility of rock slips ofthe type encountered at Kadamparai, safe andcontrolled blasting techniques should beevolved beforehand to suit the requirements ofstrata encountered.

THANK YOU !