scholarly journals Tunneling in Khimti Hydropower Project, central Nepal

1996 ◽  
Vol 14 ◽  
Author(s):  
S. C. Sunuwar ◽  
B. O'Neill
Keyword(s):  
Rock Mass ◽  
Correct Choice ◽  
The Self ◽  
Hydropower Project ◽  
Supporting Capacity ◽  
Rock Support ◽  
Geological Investigation ◽  
Tunnel Support ◽  
Central Nepal

The role of geology is very important in any underground excavation. Proper geological investigation reduces the overall cost of a project and saves time. It is important to understand and be able to predict the behaviour of a rock mass before designing the support system. In good quality rock, the self-supporting capacity of rock mass should be used to its maximum advantage and the amount of rock support kept to a minimum. In the Khimti Hydropower Project the tunnel support will be designed to take optimum advantage of the self-supporting capacity of rock mass and the correct choice of support systems. The rocks encountered in the tunnels at Khimti will be logged in accordance with the Q-classification system. The experience in desigining tunnel support that has been developed in Norway will be used to this project as well.

scholarly journals Rock support in hydropower projects of Nepal: case studies

2006 ◽  
Vol 34 ◽  
pp. 29-38
Author(s):  
Subas Chandra Sunuwar
Keyword(s):  
Rock Mass ◽  
Large Diameter ◽  
Design Guidelines ◽  
Rock Mass Classification ◽  
Classification Systems ◽  
Rating Systems ◽  
Rock Support ◽  
Support Design ◽  
Tunnel Support ◽  
Mass Classification

The principal objective of rock support is to assist the rock mass to support itself. One common example is where the rock support system (e.g. rock bolts and shotcrete) actually becomes integrated with the rock mass. Rock support strengthens the rock mass surrounding an excavation by creating a reinforced zone, which maintains the integrity of the excavated surface, possesses sufficient flexibility to allow for the redistribution of stresses around the excavation, and has enough stiffness to minimise the dilation (opening) of discontinuities. Rock mass classification systems are used worldwide as a basis for tunnel support design. The Q and Rock Mass Rating systems have been extensively applied in rock support design on most of the hydropower projects in Nepal. Generic design guidelines based on rock mass classification systems cannot provide suitable rock support for every site. Therefore some modifications are necessary to suite the site-specific ground conditions including local rock mass and geological hazards. There are relatively few tunnels excavated in the tectonically active Nepal Himalaya. Large diameter tunnels in Nepal are commonly lined with concrete whereas recently smaller-diameter tunnels are either shotcrete-lined or left unsupported. "Leaky" lining has been used in most of the projects to avoid the heavy reinforcement needed to withstand the occasional very high external water pressures.

scholarly journals Engineering Geological Investigation of dam site of proposed Sunkoshi-2 Hydropower Project, Khurkot area, eastern Nepal

2019 ◽  
Vol 58 ◽  
pp. 181-188
Author(s):  
Bipin Adhikari ◽  
Ujjwal Acharya ◽  
Kamala Kant Acharya ◽  
Subesh Ghimire
Keyword(s):  
Rock Mass ◽  
Geological Mapping ◽  
Hydropower Project ◽  
Rock Masses ◽  
Geological Investigation ◽  
Dam Foundation ◽  
Rock Types ◽  
Stability Against Sliding ◽  
Dam Site ◽  
Selection Of

The dam site of proposed Sunkoshi-2 Hydropower Project and its surrounding mainly comprise the Tawa Khola Formation, which is the basal formation of the Bhimphedi Group. Although garnet schist and micaceous quartzite bands are the main rock types; three rock units namely- Schist Unit, Quartzite Unit, and Gneiss Unit were identified. Engineering geological mapping followed by discontinuity survey were carried out. The result exhibited differences in fracture intensity and discontinuity characteristics of rock masses according to rock type. Since joint orientations were found to be consistent over fairly large areas, surface studies of joints were used in predicting subsurface orientations. Rock mass classification was made in line with the Rock Mass Rating System (RMR) and the Dam Mass Rating (DMR) classification for the dam foundation. The rock masses were classified onto fair to good rock classes according to RMR value. Dam foundation analysis regarding stability against sliding using DMR classification helped in selection of suitable dam-axis among two alternatives. Water Quality Standards (2005).

scholarly journals Engineering geological characteristics based on rock mass rating (RMR) and geological strength index (GSI) in Tunnel Number 1 of the Sigli-Aceh toll road

2021 ◽  
Vol 325 ◽  
pp. 01014
Author(s):  
Jabnes Satria ◽  
I Gde Budi Indrawan ◽  
Nugroho Imam Setiawan
Keyword(s):  
Rock Mass ◽  
Poor Quality ◽  
Geological Mapping ◽  
Geological Strength Index ◽  
Rock Mass Rating ◽  
Strength Index ◽  
Geological Investigation ◽  
Tunnel Support ◽  
Toll Road ◽  
Tunnel Number

This paper presents engineering geological investigation results in the form of rock mass characteristics for tunnel number 1 of the Sigli-Aceh toll road. The investigation was carried out through geological mapping, core drill evaluation, and laboratory tests. In this research, the rock mass rating (RMR) and Geological Strength Index (GSI) were applied for the rock mass classifications. The measurement of rock mass quality is then used to determine the excavation method and tunnel support system on the SigliAceh toll road. The results showed that the research location consisted of calcareous sandstone with poor to good-quality (GSI (21.7 - 85.5), RMR (32.0 - 67.6)), and sandstone with good quality (GSI (86.3 - 86.9), RMR (64.0 - 65.0)). The poor quality rock masses were mainly caused by weathering effect. In addition, this research also analyzes the relationship between RMR and GSI based on the type and quality of rocks in the research location so that this correlation can be used in other areas with similar rock type and quality to this research location.

scholarly journals Construction of a tunnel under thin rock overburden in Middle Marsyangdi Hydroelectric Project, Central Nepal

2004 ◽  
Vol 29 ◽  
Author(s):  
Kaustubh Mani Nepal
Keyword(s):  
Rock Mass ◽  
Support System ◽  
Deformation Monitoring ◽  
Actual Condition ◽  
Support Design ◽  
Tunnel Support ◽  
Hydroelectric Project ◽  
Central Nepal ◽  
Rock Overburden ◽  
Smooth Blasting

This paper deals with an application of New Australian Tunnelling Method (NATM) in low cover tunnelling in Lesser Himalaya of Nepal. The length of the tunnel is 365.8 m with a 8.2 m finished diameter. The average thickness of the rock overburden is 16- 18 m with a maximum of 30 m, whereas average side cover is 40 m. Top heading and multiple benching methods were applied for tunnelling work. The rational support design techniques were conceived together with Bieniawski's Support Guideline for each standard support classes. Standard initial support system was designed according to NATM, to provide complete stabilization of excavation. It consisted of a combination of systematic rock bolts and shotcrete.  The smooth blasting technique was adopted for the tunnel excavation. The specific charge was 1.39-1.47 kg/m3 A special emphasis was given in the collection of discontinuity data so that the rock mass could be evaluated effectively. Geomechanics classification for rock mass was used for the rock mass evaluation. The rock mass was also back evaluated by using Q and GSI classification on the basis of installed support. After the careful assessment of the data, the rock mass in the tunnel was classified into fair to poor according to RMR and Q and blocky / disturbed to very blocky / fair according to GSI. The rock mass parameters collected during the construction stage agree with the data collected at surface during feasibility and tendering stages. The rock mass classification based on the surface outcrop survey and drillings was a considerable success and found to be very close to the actual condition. The effectiveness of revised support system with steel rib was found to be negligible or minimum for tunnel support. Rock support deformation monitoring in the tunnel was regularly carried out to determine the efficiency and adequacy of the installed support.

The role of the self in creative expression

2014 ◽  
Author(s):  
Kristin Donnelly ◽  
Radmila Prislin ◽  
Ryan Nicholls
Keyword(s):  
Creative Expression ◽  
The Self

The role of the self in organizational justice

2007 ◽  
Author(s):  
D. Ramona Bobocel ◽  
Russell E. Johnson ◽  
Joel Brockner
Keyword(s):  
Organizational Justice ◽  
The Self

The role of egocentrism in estimating social evaluations of the self

2004 ◽  
Author(s):  
John Chambers ◽  
Nick Epley ◽  
Paul Windschitl
Keyword(s):  
The Self

From Container to Claustrum: Projective Identification in Couples

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Tamara Feldman
Keyword(s):  
Psychological Health ◽  
Projective Identification ◽  
The Self ◽  
The Other ◽  
Intimate Partners ◽  
And Control ◽  
The Relationship ◽  
As If

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.

Sign in / Sign up

Export Citation Format

Share Document