Controlled blasting in underground construction: A case study of a tunnel plug demolition in the Neelum Jhelum hydroelectric project

ABSTRACT Karst-related geo-disasters often occur in karst regions during underground construction. In recent years, a number of shallow buried karst features have been discovered in eastern China. Survey boreholes show that karst caves exist at depths of 26–30 m and 33–36 m, which are typical of shallow buried karst. Using cross-hole seismic computed tomographic techniques, 36 geological anomalies consisting of 26 mud-filled caves, three empty caves, and seven fissure zones/loose lens bodies were detected. Most of the karst caves were oblate or oval. After determining the scale of and the connection between the caves, the study area was divided into two areas to provide advice on the treatment of caves during construction. An analysis of the development characteristics of the karst suggests that karst is controlled by several key factors, including topography, structural features, groundwater conditions, and human activities. Following an analysis of these factors and field studies of the process of formation of the shallow buried caves, solutions are proposed to prevent karst-related geo-hazards. The research results can be used in the design of foundations for buildings that are located in regions that include shallow buried karst in eastern China.

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Stabilization Measure Adopted for Controlling Landslide: A Case Study of Upper Mai Hydroelectric Project

Hydro Nepal Journal of Water Energy and Environment ◽

10.3126/hn.v21i0.17815 ◽

2017 ◽

Vol 21 ◽

pp. 11-14 ◽

Cited By ~ 1

Author(s):

Kanchan Chaulagai

Keyword(s):

Water Management ◽

Economic Loss ◽

Vital Role ◽

Rock Bolts ◽

Safety Risk ◽

Hydroelectric Project ◽

Stability Measure ◽

History Effects ◽

Landslide Stabilization

Stability is the key issue in landslide stabilization. Methodology and component adopted in stabilizing the slide play vital role in this regards. In many occasion, stability measure adopted for controlling slide has been found to be unsuccessful, inadequate causing not only the safety risk but also huge economic loss. This paper describe history, effects, causes, stabilization measures and effectiveness of these measures played for controlling landslide of headwork area of Upper Mai Hydroelectric Project. The pioneering solution applied for landslide stabilization such as application of rock bolts, shotcrete and water management found to be highly effective in controlling the landslide. HYDRO Nepal JournalJournal of Water Energy and EnvironmentIssue: 21, July, 2017Page: 11-14Upload Date: July 18, 2017

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Value-based argumentation for policy decision analysis: methodology and an exploratory case study of a hydroelectric project in Québec

Annals of Operations Research ◽

10.1007/s10479-014-1774-4 ◽

2015 ◽

Vol 236 (1) ◽

pp. 233-253 ◽

Cited By ~ 7

Author(s):

Jasmin Tremblay ◽

Irène Abi-Zeid

Keyword(s):

Decision Analysis ◽

Policy Decision ◽

Hydroelectric Project ◽

Exploratory Case Study ◽

Analysis Methodology

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Prevalent Health Problems among Nepalese Underground Construction Workers

Journal of Environmental and Public Health ◽

10.1155/2020/9436068 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Rajan Ghimire ◽

Ganesh Prasad Neupane

Keyword(s):

Acute Gastroenteritis ◽

Workplace Safety ◽

Health Problems ◽

Construction Workers ◽

Upper Respiratory Tract ◽

Underground Construction ◽

Chi Square ◽

Respiratory Problems ◽

Hydroelectric Project ◽

Heavy Construction

Background. Workplace is associated with exposure to various products, which can be associated with adverse health outcomes. It is true with underground construction work. This study calculated the prevalence of common health problems among Nepalese underground construction workers in comparison to heavy construction workers. This type of study is rare in the context of Nepal and other developing countries, and we hope that the findings will help to take precautions for the prevention of these conditions. Method. It was a retrospective study based on the clinical record of outpatient cases and general health checkups of all Nepalese workers available at the Project clinic, Upper Tamakoshi Hydroelectric Project, Gongar, Bigu, Dolakha. We studied three hundred and ninety-eight workers. We used multipurpose analysis and conducted the Chi-square test and calculated correlations and odds ratios. Results. Two hundred and sixteen (54.3%) participants worked inside the tunnel, and 182 (43.2%) participants worked outside the tunnel. Respiratory disease, mainly upper respiratory tract infection (URTI) (23.4%), is the most common presentation among construction workers followed by injuries (16.7%). Injuries and hypertension were significantly higher in inside the tunnel workers, and acute gastroenteritis was significantly ( p value <0.05) higher in outside the tunnel workers. Increasing age increased the chance of hypertension and cutaneous fungal infection among construction workers. Further studies are required for the analysis of risk factors associated with these health conditions. Conclusion. Respiratory problems are the most common health problem in underground construction workers; however, injuries and hypertension were significantly higher in tunnel workers. Acute gastroenteritis was significantly higher among outside the tunnel workers. Workplace safety should be the priority of every construction site, especially focusing to prevent respiratory problems, injuries, and accidents.

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Impact of Construction Method and Ground Composition on Headrace Tunnel Stability in the Neelum–Jhelum Hydroelectric Project: A Case Study Review from Pakistan

Applied Sciences ◽

10.3390/app11041655 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1655

Author(s):

Hafeezur Rehman ◽

Abdul Muntaqim Naji ◽

Kyoungmin Nam ◽

Saeed Ahmad ◽

Khan Muhammad ◽

...

Keyword(s):

Successful Operation ◽

Tunnel Excavation ◽

Cost Overruns ◽

Tunnel Stability ◽

Hydroelectric Project ◽

Related Data ◽

Headrace Tunnel ◽

Excavation Area

During underground construction, the behavior of the ground is influenced by characteristics of the rock mass with situ stresses and ground water, cross section of the excavation area, excavation method, and the rate of excavation. These fundamental features are considered to ensure the support and stability of underground excavations and achieve long-term successful operation. However, the ground composition of the Himalayas hinders tunnel excavation, especially in case of mechanized tunneling; this causes time and cost overruns. This study has reviewed the recently completed Neelum–Jhelum Hydroelectric Project; the project complexities, geological environments involving significant overburden and tectonic stresses, and effects of the excavation method on tunnel stability were analyzed. The major challenges that were encountered during construction are discussed herein along with their countermeasures. An analysis of project-related data reveals that latest techniques and approaches considering rock mechanics were used to complete the project; the existing approaches and methods were accordingly verified and extended. Apart from ground composition, the excavation methods used play an important role in the occurrence of severe rock bursts. Thus, the findings of this study are expected to be helpful for future tunneling projects in the Himalayas.

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Effect of Sand Erosion on Turbine Components: A Case Study of Kali Gandaki “A” Hydroelectric Project (144 MW), Nepal

Hydro Nepal Journal of Water Energy and Environment ◽

10.3126/hn.v17i0.13270 ◽

2015 ◽

Vol 17 ◽

pp. 24-33 ◽

Cited By ~ 5

Author(s):

Balendra Chhetry ◽

Kumar Rana

Keyword(s):

Suspended Sediment ◽

Sediment Load ◽

Hydroelectric Plant ◽

Suspended Sediment Load ◽

Sediment Erosion ◽

Hydroelectric Project ◽

Power Stations ◽

Sand Erosion ◽

High Sediment

In high sediment laden river projects or silt affected power stations, the frequency of repair and maintenance of underwater parts is comparatively higher which leads to increase the overall forced outages per year for repair The extent of the major maintenance will depend on the operating condition such as suspended sediment load passing through the turbine and how the machine was loaded during the operation. This paper illustrates the analysis of sediments, effect of sand erosion and maintenance of turbine of Kali Gandaki “A” Hydroelectric Plant (144 MW). The paper also describes the repair methods used for different turbine components to minimize the effects induced by sediment erosion. HYDRO Nepal JournalJournal of Water, Energy and EnvironmentIssue: 17, July 2015

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