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In the recent past, infrastructure development activities have gained momentum in Nepal. Many roads are being and will be upgraded to enhance transport efficiency. The hydropower development activities are in full momentum. However, frequently occurring natural hazards caused by monsoon rain and large-scale earthquakes are major challenges to Nepal’s endeavors of infrastructure and hydropower development. Developing an efficient transport network functioning in all-weather conditions and resilient hydropower is not possible without the construction of tunnels. The experience indicates that the construction cost for tunnels is considerably higher due to insufficient capacity and knowledge base within Nepal and dependency on foreign agencies who have limited knowledge on the Himalayan geological condition. It is important to build capacity through specialized high-level education and research within Rock and Tunnel Engineering both at MSc and Ph.D. levels. This paper discusses a new curriculum developed for MSc education in Rock and Tunnel Engineering for the Institute of Engineering (IoE) of Tribhuvan University with the support of the Norwegian University of Science and Technology (NTNU). It has started the MSc program and first batch of students has been enrolled for the academic year 2020/2021 at IoE-WRC Pokhara. NTNU collaborates with IoE through a research grant NORHED II Project 70141 6; Capacity Enhancement in Rock and Tunnel Engineering in Nepal received from the Norwegian Agency for Development Aid (NORAD). Capacity Enhancement in Rock and Tunnel Engineering in Nepal

The use of unlined / shotcrete lined pressure tunnels and shafts are very cost effective solutions for the hydropower project and therefore are being implemented worldwide. However, the ground conditions at the area of concern should be favorable regarding both minimum principal stress magnitude and rock mass strength, which should be higher than the hydrostatic head act-ing on the tunnel periphery. In addition, the rock mass should be relatively unjointed or joints in the rock mass should be tight enough. The most vulnerable issue in the design of unlined high-pressure headrace tunnel is to insure the potential leakage out of the tunnel during operation is within acceptable limit. This manuscript assesses the potential leakage extent from a shotcrete lined high-pressure headrace tunnel of the Upper Tamakoshi Hydroelectric Project (UTHP) in Nepal. Most of the headrace tunnel at UTHP is supported suing sprayed concrete (shotcrete) in combination of rock bolting in the walls and the crown and concrete lining in the invert. The downstream stretch (at surge shaft area) of few hundred meters headrace tunnel will be support-ed with full concrete lining. The approximately 8 km long headrace tunnel will face a maximum hydro-static pressure head of up to 120 m during power plant operation. The preliminary results of the leakage assessment using approach suggested by Panthi (2006) indicates that the average specific leakage from the headrace tunnel will be around 2.7 l/min/m tunnel. The evaluation concludes that the outer reach of the headrace tunnel after chainage 7300 m is extremely vul-nerable for excessive water leakage to occur during operation. The joint set dipping towards the valley side slope of Gongar Khola seem very critical for potential water leakage, suggesting re-medial measure before water filling in the tunnel.

The flatjack test is normally used to measure the average normal stress at a rock surface and to evaluate the rock mass deformation modulus. The aim of this manuscript is to present a modified variant of the flatjack test for the long-term monitoring of pressure and deformation development in the headrace tunnel of Moglicë hydropower project. The aim is to determine the behavior of the rock mass after water filling of the tunnel and during the first year of operation. The monitoring rig installed will continuously record pressure and deformation development in the rock mass behind the shotcrete liner and data will be stored in the dataloggers submerged in the headrace tunnel. This application is, to the authors’ knowledge, one of the first of its kind in hydropower construction. Since data acquisition will not be possible before 2020, this manuscript presents modified test procedure of the flatjacks and rig as a whole. The practical challenges experienced during the instrumentation process of the rig is highlighted.

There are no clearly defined rules for the investigation procedures of swelling rocks. Difficulties are generally met for characterization and testing of swelling rocks and for prediction of the response to tunnel excavation. The waterway tunnels of hydropower projects and other water tunnels are even special since these tunnels are persistently exposed to the moisture changes caused by flowing water. Reported case histories have shown that severe stability problems have been experienced during the operation of hydropower plant caused by swelling of rocks. This important issue needs to be investigated thoroughly. Different laboratory oedometer testing methodologies have been developed and proposed in recent years by different institutions to carry out testing of swelling of the rocks. However, there is no standard methodology to assess the swelling behavior under moisture changes nor the application of the results obtained from powder tests. The site-specific swelling rock potential including moisture changes should be investigated with effective diagnostic methods, which provide reliable data for the considerations and decisions to be made. The main aim of this manuscript is to provide insight and qualitative description of the laboratory methods in operation at two leading laboratories in rock mechanics; i.e. Norwegian University of Science and Technology (NTNU) of Norway and Karlsruhe Institute of Technology (KIT) of Germany, in order to determine the swelling potential of various rocks through cyclic testing. Oedometer swelling tests on pulverized material as well as intact rock discs have been performed at these two laboratories; i.e. at NTNU and KIT. The manuscript highlights the results of the swelling tests from both laboratories, and comparisons and discussions of the testing methodology at these two institutions are made. Locked until 15.5.2019 due to copyright restrictions. This is an Accepted Manuscript of a book chapter published by Routledge/CRC Press in [Geomechanics and Geodynamics of Rock Masses: Proceedings of the 2018 European Rock Mechanics Symposium] on [15 May 2018], available online: https://doi.org/10.1201/9780429462078

Rock burst / rock spalling is among the prevailing stability challenges, which can be met while tunneling through hard rock mass. Especially, this is very relevant for the mountainous country like Norway where hard rock is dominating and many road, railway and hydropower tunnels have to be aligned deep into the mountain with steep valley slope topography. Tunnels passing beneath deep rock cover (overburden), in general, are subjected to high in-situ stresses. If the rock mass is relatively unjointed and massive, which is the most likely case in Norway, a brittle failure may occur in the tunnel periphery, which is known as rock spalling / rock bursting. Establishing state of the stress and evaluating stress induced instability in tunnels passing through brittle rock mass at relatively greater depth is of course a challenge. This manuscript reviews and describes the existing rock burst prediction methods that are being practiced worldwide so that these can be used by professional engineers as base for the evaluation and predict potential rock burst / rock spalling scenario in the tunnels under planning and design. The manuscript describes each method itself, highlights extent of applicability and compares with other prediction methods. Published by Norsk Forening for Fjellsprengningsteknikk, Norsk Bergmekanikkgruppe og Norsk Geoteknisk Forening Oslo

For clay minerals the swelling mechanisms and factors influencing on the swelling potential is widely explained and confirmed through comprehensive research. When it comes to intact rocks there are questions regarding both swelling potential and main reasons for swelling in the different rock types. It is therefore important to better understand the swelling behaviour of different rocks rich in clay minerals when in contact with water. In this pretext, an extensive laboratory work has been performed to address a study on the expansive character of intact rock. Three different rock types have been tested; alum shale, greenschist and tuff, and the rocks vary in both structure and mineral composition. Three traditional test methods consisting swelling pressure determination using dust powder, rock cylinders and free swelling have been used. In addition, recently developed new test apparatus at NTNU/SINTEF lab has also been used. The benefit of this method is that it gives possibility to look on the swelling strain of rock cubes when submerged in all three directions. When exposed to water the displacement in all three directions is recorded over time. Results of all swelling test methods are compared. Further discussions are made on the swelling impact based on mineralogical composition. The applicability of this new method in comparisons to the other test methods is also discussed. Published by Norsk Forening for Fjellsprengningsteknikk, Norsk Bergmekanikkgruppe og Norsk Geoteknisk Forening Oslo