Course

Unit 1

Introduction to underground constructions and tunnelling:- General Description of Various Tunnels and other underground structures, Components of a tunnel, Stress around an underground opening, Methods of excavations, Subsurface investigation

Surface investigation, Sampling Techniques, Laboratory and in-situ testing of soil and rock, Indian standard codes

Unit 2

Construction, challenges and solutions for Caverns, shaft and underground stations:- Factors affecting the choice of method of tunnel construction, Cut and cover method, Bored method, Drill and blast method, Sequential excavation method and shaft method, Norwegian tunnel boring method (NTM), New Austrian tunnel boring method (NATM), Methods of construction of caverns and shafts and underground stations, Challenges and solutions for execution of these methods, Different types of Tunnel boring machines

Design methodology, Instrumentation and monitoring for tunnels:- Rock mass classification, Geotechnical and geological inputs for design, Empirical, semiempirical and joint set analysis, Numerical 2D modelling and final support recommendations, Need for Instrumentation and monitoring in tunnels, Types of Instruments – Planning and execution Unit 3

Support systems and design software for tunnels:- Need for pre-excavation support system, Fore piling, Bolts and Anchors, Shotcrete, wire meshes, lattice girders and integrated support systems, Different types of retaining structures and their applicability. Secant piles, Sheet piles, contiguous piles and soldier piles and D wall. Requirement of investigation to be carried out for underground structure, Preparation geotechnical interpretation report for design of retaining structure, Numerical analysis to be performed for temporary / permanent retaining system, Introduction to software to be used in embedded retaining system, Case studies.

Introduction to interpretation using Rock data, Introduction to necessary software’s and their practical application & case studies

Course Objectives

To provide insight into underground structures

To provide exposure to the rock strength and design considerations.

Course Outcome

CO1: Comprehend the different soil investigation techniques, rock mass classifications, components of different underground structures and their functions

CO2: Design and apply different construction methodologies for tunnels, Caverns and shafts in different soil and rock conditions.

CO3: Evaluate the suitability of different excavation supports such as sheet piles, soldier piles, diaphragm walls and tunnel support for different soil and rock conditions

CO4: Create an instrumentation monitoring plan for tunnel construction

CO5: Comprehend the use of different software tools in deep excavations and apply code provisions for mitigating water ingress and seepage in excavations and tunnels 

CO-PO Mapping

• CA – Can be Quizzes, Assignment, Projects, and Reports

1. CIRIA -C760 “Guidance on Embedded retaining wall design”
2. Jaeger, C., Cook, N.G.W, Zimmerman, R.W. (2007). Fundamentals of Rock Mechanics, 4th Edition. Blackwell, U.K., 475 p.
3. Goodman, E. (1989). Introduction to Rock Mechanics, 2nd Edition. John Wiley and Sons, New York, NY, 562 p.