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61.
62.
Pawan Kumar Singh Arvind Kumar Mishra Deepanshu Ranjan Singh 《Journal of the Geological Society of India》2017,89(3):307-314
Indian coal mining industry is in transition phase with the growing demand of coal and is likely to escalate further with the need of ultra-mega power projects as well as announcement of smart cities projects. Although, there exist sufficient coal reserves in India, continuous acquisition and possession of coal bearing land is required to minimize the existing gap prevailing between coal demand and supply.The solution of the problem lies not only in modification of laws and policies of industry, but also in modification of mining engineering practices towards sustainable development. This paper critically examines the cause of the problem in the light of Indian laws and practices of the industry. In this paper a method of exact reclamation of post-mining land has been designed as a solution to make easier land acquisition by way of proposing a system of returning back the exact reclaimed land to its owners under corporate social responsibility activity of the industry. The proposed conceptual model of interlinking corporate social responsibility with land exchange will encourage sustainable development practice by mining engineers, and may turn around the public image of the industry. 相似文献
63.
An analytical method has been proposed to predict the ultimate uplift capacity of single vertical piles embedded in sand considering
arching effect. The present analysis takes into consideration of various pile and soil parameters such as length (L), diameter (d) of the pile, angle of internal friction of soil (ϕ), soil pile friction angle (δ) and unit weight of soil (γ). A modified value of coefficient of lateral earth pressure in uplift has been developed considering the arching effect of
soil. A comparative assessment of the uplift capacity of piles predicted by using proposed theory and the existing available
theories is made with the existing field and model test results. It has been observed that the present model considering the
arching effect predicts the results closer. 相似文献
64.
Sobolev's probabilistic method — The method of quantum exit from the medium — has been applied to solve the transfer equation for the case of interlocking without redistribution. The solution contains the function (x) which is same as theH-function involved in the solution given by Busbridge and Stibbs the method of principle of invariance. 相似文献
65.
A size-continuous breakage-kinetics model is postulated and supported with industrial grinding-mill data. It is shown that the kinetics parameters include the effects of possible classification at the mill discharge. The estimated parameters were then used in the kinetics model to simulate the behavior of a grinding mill in open- and closed-circuit operation. While material transport and kinetics are equally important in open-circuit operation, heavy recycle in a closed circuit makes a detailed material-transport model for grinding unnecessary. In effect, the mill can be considered as backmixed. This suggests that more emphasis should be placed on modelling the classifier than the development of detailed material-transport models for the grinding mill. 相似文献
66.
Dhruba Mukhopadhyay Mohan C. Baral Ranjan K. Niyogi 《Journal of Earth System Science》1997,106(4):259-276
The banded iron-formation in the southeastern Bababudan Hills display a macroscopic synformal bend gently plunging towards
WNW. The bedding planes in smaller individual sectors show a cylindrical or conical pattern of folding. The dominant set of
minor folds has WNW-ESE trending axial planes and the axes plunge towards WNW at gentle to moderate angles, though there is
considerable variation in orientation of both axes and axial planes. A later set of sporadically observed folds has N-S trending
axial planes. The macroscopic synformal bend within the study area forms the southeastern corner of a horseshoe shaped regional
synformal fold closure which encompasses the entire Bababudan range.
The minor folds are buckle folds modified to a varying extent by flattening. In some examples the quartzose layers appear
to be more competent than the ferruginous layers; in others the reverse is true. The folds are frequently noncylindrical and
the axes show curvature with branching and en echelon patterns. Such patterns are interpreted to be the result of complex
linking of progressively growing folds whose initiation is controlled by the presence of original perturbations in the layers.
Domes and basins have at places developed as a result of shortening along two perpendicular directions in a constrictional
type of strain. Development of folds at different stages of progressive deformation has given rise to nonparallelism of fold
axes and axial planes. The axes and axial planes of smaller folds developed on the limbs of a larger fold are often oriented
oblique to those of the latter. Progressive deformation has caused rotation and bending of axial planes of earlier formed
folds by those developed at later stages of the same deformational episode. Coaxial recumbent to nearly reclined fold locally
encountered on the N-S limb of the macroscopic fold may belong to an earlier episode of deformation or to the early stage
of the main deformation episode.
The E-W to ESE-WNW strike of axial plane of the regional fold system in the Bababudan belt contrasts with the N-S to NNW-SSE
strike of axial planes of the main fold system in the Chitradurga and other schist belts of Karnataka. 相似文献
67.
K. Naha A. Rai Choudhuri V. Ranjan R. Srinivasan 《Journal of Earth System Science》1995,104(3):327-347
The supracrustal enclave within the Peninsular Gneiss in the Honakere arm of the Chitradurga-Karighatta belt comprises tremolite-chlorite
schists within which occur two bands of quartzite coalescing east of Jakkanahalli(12°39′N; 76°41′E), with an amphibolite band
in the core. Very tight to isoclinal mesoscopic folds on compositional bands cut across in the hinge zones by an axial planar
schistosity, and the nearly orthogonal relation between compositional bands and this schistosity at the termination of the
tremolite-chlorite schist band near Javanahalli, points to the presence of a hinge of a large-scale, isoclinal early fold
(F1). That the map pattern, with an NNE-plunging upright antiform and a complementary synform of macroscopic scale, traces folds
'er generation (F
2),is proved by the varying attitude of both compositional bands (S0) and axial pranar schistosity (S
1), which are effectively parallel in a major part of the area. A crenulation cleavage (S
2) has developed parallel to the axial planes of theF
2 folds at places. TheF
2 folds range usually from open to rarely isoclinal style, with theF
1 andF
2 axes nearly parallel. Evidence of type 3 fold interference is also provided by the map pattern of a quartzite band in the
Borikoppalu area to the north, coupled with younging directions from current bedding andS
0
-S
1 inter-relation.
Although statistically theF
1 andF
2 linear structures have the same orientation, detailed studies of outcrops and hand specimens indicate that the two may make
as high an angle as 90°. Usually, in these instances, theF
1 lineations are unreliable around theF
2 axes, implying that theF
2 folding was by flexural slip. In zones with very tight to almost isoclinalF
2 folding, however, buckling attendant with flattening has caused a spread of theF
1 lineations almost in a plane. Initial divergence in orientation of theF
1 lineations due to extreme flattening duringF
1 folding has also resulted in a variation in the angle between theF
1 andF
2lineations in some instances. Upright later folding (F3) with nearly E-W strike of axial planes has led to warps on schistosity, plunge reversals of theF
1 andF
2 axes, and increase in the angle between theF
1 andF
2 lineations at some places. Large-scale mapping in the Borikoppalu sector, where the supposed Sargur rocks with ENE ‘trend’
abut against the N-‘trending’ rocks of the Dharwar Supergroup, shows a continuity of rock formations and structures across
the hinge of a large-scaleF
2 fold. This observation renders the notion, that there is an angular unconformity here between the rocks of the Sargur Group
and the Dharwar Supergroup, untenable. 相似文献
68.
Nihar Ranjan Patra Prabhakar Jagannath Pise 《Geotechnical and Geological Engineering》2006,24(2):265-282
Experimental investigations on model pile groups of configuration, 1 × 1(single pile), 3 × 1, 2 × 2 for embedment length to
diameter ratio, L/d = 38, were conducted in uniform dry medium dense Ennore sand. The spacing of piles in the groups varied from 3 to 6 pile
diameter. Soil–pile friction angles were δ = 16° and 28°. The pile groups were subjected to oblique pulling loads at angles θ = 0°, 30°, 60° and 90° with the vertical central axis of the groups. The load–displacement response, oblique ultimate pulling
resistances have been qualitatively and quantitatively studied. The inclinations of the load, at which maximum oblique resistance
for the groups were observed, have been reported. Predictions of ultimate resistance of pile groups under uplift, lateral
and oblique pulling loads have been carried out respectively by the methods of Patra and Pise (2002) (Electronic Journal of Geotechnical Engineering, 8, Bundle B), Patra and Pise (2001) (Journal of Geotechnical and Geoenvironmental Engineering ASCE, 127(6), 481–487) and Chattopadhyay and Pise (1986c) (Proceedings of IST East Asian Conference on Struct Engineering and Const., Vol. 1, pp. 1632–1641). A comparison of the measured values of the Writers and others with the predicted values showed
reasonable agreement. 相似文献
69.
Pulakesh Das Mukunda Dev Behera Nitesh Patidar Bhabagrahi Sahoo Poonam Tripathi Priti Ranjan Behera S K Srivastava Partha Sarathi Roy Praveen Thakur S P Agrawal Y V N Krishnamurthy 《Journal of Earth System Science》2018,127(2):19
As a catchment phenomenon, land use and land cover change (LULCC) has a great role in influencing the hydrological cycle. In this study, decadal LULC maps of 1985, 1995, 2005 and predicted-2025 of the Subarnarekha, Brahmani, Baitarani, Mahanadi and Nagavali River basins of eastern India were analyzed in the framework of the variable infiltration capacity (VIC) macro scale hydrologic model to estimate their relative consequences. The model simulation showed a decrease in ET with 0.0276% during 1985–1995, but a slight increase with 0.0097% during 1995–2005. Conversely, runoff and base flow showed an overall increasing trend with 0.0319 and 0.0041% respectively during 1985–1995. In response to the predicted LULC in 2025, the VIC model simulation estimated reduction of ET with 0.0851% with an increase of runoff by 0.051%. Among the vegetation parameters, leaf area index (LAI) emerged as the most sensitive one to alter the simulated water balance. LULC alterations via deforestation, urbanization, cropland expansions led to reduced canopy cover for interception and transpiration that in turn contributed to overall decrease in ET and increase in runoff and base flow. This study reiterates changes in the hydrology due to LULCC, thereby providing useful inputs for integrated water resources management in the principle of sustained ecology. 相似文献
70.
Arvind Kumar Mishra Manamohan Rout Deepanshu Ranjan Singh Sakti Pada Jana 《Geotechnical and Geological Engineering》2018,36(1):89-94
The demand for coal from surface mining projects are on the higher side like never before for which blasting is the basic unit operation. The explosive plays an important role in blasting and also influence the explosive-rock interaction. The most common explosive type used in surface mines is emulsion explosives. This paper presents the study on the detonation velocity of bulk emulsion explosives due to variation in gassing agent and density. In this study Sodium Nitrite (NaNO2) has been used as the gas generating additive and the performance of emulsion explosives with different concentrations of gassing agents at different temperatures has been observed. This study was undertaken to also understand the cyclic variation of temperature on gassing kinetics and performance of explosive. The effect of cooling on detonic-behaviour of bulk emulsion explosives has also been studied and presented in this paper. 相似文献