A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban...A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban areas. Tunnelling through weak and jointed rock masses such as the one in the Himalayas is a challenging task for the planners, designers, engineers and geologists because of high overburden, thickly vegetated surface, weak, poor and fragile rocks and highly varying geology with the presence of numerous small and big shear zones, faults, etc. Due to these reasons, various tunnelling problems have been faced in the past and are still being encountered. Failures and the problems may be regarded as challenges and opportunities for generating new knowledge base and thereby increasing self-reliance in tunnelling. The experiences of Himalayan tunnelling through weak and fragile rocks covering varying and mixed geology, understanding on tunnelling in squeezing ground conditions and applicability of TBM in Himalayas are presented. It has also been highlighted that the probe holes planning, drilling and monitoring shall be followed seriously to reduce the geological surprises.展开更多
The aim of the study was to evaluate the impacts of the transition from wood fuel to Liquefied Petroleum Gas （LPG） from energy use and health perspectives along an altitudinal gradient （viz., lower altitude; middle...The aim of the study was to evaluate the impacts of the transition from wood fuel to Liquefied Petroleum Gas （LPG） from energy use and health perspectives along an altitudinal gradient （viz., lower altitude; middle altitude; and higher altitude） of the Central Himalayas. Empirical field study and questionnaire based survey was conducted for obtaining the data. A total of 2o households from each altitude were selected for obtaining reliable information on the actual quantity of fuelwood consumed. Of the 2o households, five households each based on the family size i.e., small families （〈4 members）, medium （5-8 members） and large （〉9 members） from all the altitudinal regions were selected. This was followed by an administration of a questionnaire on the quantity of fuelwood consumed. After the completion of the questionnaire survey, the data was validated using a weighted survey for the randomly selected households for obtaining precise information on the actual quantity of fuelwood consumed. Energy analysis is done with respect to the time spent on fuelwood collection and energy value of burning of per kg of fuelwood. Study indicates that declining biomass requirement from forests contributes significantly towards energy conservation, also has positive impact on human health. Per capita annual energy expenditure on collection of fuelwood is 752 MJ which is higher than any other activity in villages of Central Himalaya. The LPG substitution has contributed to energy saving which is equivalent to 2976-3,742 MJ per capita per year in middle and lower altitudes respectively. In the higher altitude the energy saving is calculated to be about 257 MJ per capita per year. Replacing fuelwood with LPG has made positive impact on society in terms of improving the health while reducing diseases that are caused due to indoor air pollution.展开更多
文摘A considerable amount of tunnelling has been going on in India for various projects such as hydroelectric power, irrigation, roads and railways. Most of these projects are located in Himalayas, far away from the urban areas. Tunnelling through weak and jointed rock masses such as the one in the Himalayas is a challenging task for the planners, designers, engineers and geologists because of high overburden, thickly vegetated surface, weak, poor and fragile rocks and highly varying geology with the presence of numerous small and big shear zones, faults, etc. Due to these reasons, various tunnelling problems have been faced in the past and are still being encountered. Failures and the problems may be regarded as challenges and opportunities for generating new knowledge base and thereby increasing self-reliance in tunnelling. The experiences of Himalayan tunnelling through weak and fragile rocks covering varying and mixed geology, understanding on tunnelling in squeezing ground conditions and applicability of TBM in Himalayas are presented. It has also been highlighted that the probe holes planning, drilling and monitoring shall be followed seriously to reduce the geological surprises.
文摘The aim of the study was to evaluate the impacts of the transition from wood fuel to Liquefied Petroleum Gas （LPG） from energy use and health perspectives along an altitudinal gradient （viz., lower altitude; middle altitude; and higher altitude） of the Central Himalayas. Empirical field study and questionnaire based survey was conducted for obtaining the data. A total of 2o households from each altitude were selected for obtaining reliable information on the actual quantity of fuelwood consumed. Of the 2o households, five households each based on the family size i.e., small families （〈4 members）, medium （5-8 members） and large （〉9 members） from all the altitudinal regions were selected. This was followed by an administration of a questionnaire on the quantity of fuelwood consumed. After the completion of the questionnaire survey, the data was validated using a weighted survey for the randomly selected households for obtaining precise information on the actual quantity of fuelwood consumed. Energy analysis is done with respect to the time spent on fuelwood collection and energy value of burning of per kg of fuelwood. Study indicates that declining biomass requirement from forests contributes significantly towards energy conservation, also has positive impact on human health. Per capita annual energy expenditure on collection of fuelwood is 752 MJ which is higher than any other activity in villages of Central Himalaya. The LPG substitution has contributed to energy saving which is equivalent to 2976-3,742 MJ per capita per year in middle and lower altitudes respectively. In the higher altitude the energy saving is calculated to be about 257 MJ per capita per year. Replacing fuelwood with LPG has made positive impact on society in terms of improving the health while reducing diseases that are caused due to indoor air pollution.
