Underground Coal Gasification (UCG) -A Pilot Study at Certain Area of Jamalganj Coal Basin, Joypurhat District, Bangladesh
Mohammed Masum, Mohammad Nurul Hoque, Md. Ali Akbar, Zobayer Mahmud, Md. Al Amin, Md. Abdur Razzaque, Md. Kamrul Ahsan
Page Numbers : 170-179
DOI : 10.36348/sjce.2020.v04i09.005
Geological Survey of Bangladesh has been entrusted with the responsibilities of investigation and exploration of several kinds of solid mineral resources and discovered four major Gondwana coalfields at southern slope of Rangpur saddle of Bangladesh. Underground Mining is going on only in Barapukuria coal field and the rest of coal fields mining operation at this stage still not possible due to the greater depth. Jamalganj coal basin is one of the largest coal basin of Bangladesh where underground mining method for further mining may be really difficult. Around 4000 million tons of coal deposited in that coalfield which equivalents (due to energy) to about 130 Tcf Gas. It might not be technically feasible or economically viable to mine coal resources of that coalfield till now. Potential for underground coal gasification in the specific area of Jamalganj coalfield of Bangladesh should be needed to study. It has adequate depth (600-800m) and workable overburden as well as their chemical properties of coal (Calorific value-26.84%, Sulfur content- 0.55%, Fixed carbon- 36.72%, Volatile matter- 36.92%, Moisture content and Ash content 3.58%) which might be positive sign for UCG implementation. The high-volatile to medium-volatile bituminous coal is very suitable for UCG exploration in terms of their depth of occurrence, thickness of coal seam, coal reserve and areal extent. The thickest seam-III (over 40 m) can be a primary target for UCG development especially where it combines with seam-II in the eastern part of the coalfield.
Original Research Article
Nov. 11, 2020
Socio-Economic Impacts of Transit Projects (A Case Study of Orange Line Lahore)
Alisha Shahid, Muhammad Ansub, Asra Hafeez, Hamza Saleem, Aroosa basharat
Page Numbers : 161-169
DOI : 10.36348/sjce.2020.v04i09.004
Open spaces have significant importance in the life of the settlements. The areas with high green coverage rate have ecological and environmental importance. These green spaces can improve the urban climate, abate the urban heat- island effect by their ecological-balancer function and reduce environmental damages. In recent years, less attention has been paid to open spaces (including green areas and green spaces) and their components as well as their effect on the environment. Due to mega transit projects environment of Lahore is continuously in danger. This research have highlighted the importance of green spaces which is destroyed badly after every project. Research have also highlighted the socio economic conditions, willingness of residents of Lahore where the project of orange line was initiated. In the end of the research the authors have proposed some useful measures through which planners and engineers can hold on projects and will provide less harm to environment.
Original Research Article
Nov. 5, 2020
Analysis of Penetration Mechanical Characteristics of Multi-layer Civil Engineering Materials
Yanhua She
Page Numbers : 125-136
DOI : 10.36348/sjce.2020.v04i09.001
According to the three-layer airport runway, based on spherical cavity-expansion theory and considering interface effect of concrete-macadam-soil by analyzing kinetic energy projectile penetrating layered target of concrete-macadam-soil, penetration models of concrete cratering, concrete pore-forming, macadam pore-forming and soil pore-forming are established. In addition, numerical solution of control equations is carried out by using Runge-Kutta method. And the Time-history curve of residual velocity is obtained. The theoretical analysis shows that because of the interface effect, the penetration resistance of projectile suffered on concrete layer and macadam layer when moving , is related not only to penetration velocity, mass, projectile shape and medium character, but also to penetration depth, which is the biggest difference compared with penetrating into single layer. Finally, by means of finite element simulation, the process of oblique penetrating into multilayered medium of airport runway is simulated by three dimensional numerical analysis. Thus, the influence of the penetration velocity and the boundary of the runway on the penetration process were studied. The results show that the presence of the multi-layer media interface of the runway accelerates the attitude of the projectile body; the smaller the penetration rate is, the more obvious the phenomenon is. At the same time, the overload response of projectile body is changed. The research results have laid a foundation for the further research on the technology of the composite medium penetration into the airport runway. They also have reference value for the research on the failure of civil engineering materials under the action of dynamic loads.
Original Research Article
Nov. 5, 2020
Novel Formulas for Displacements and Stresses of Thick Anisotropic Rectangular Plate
Ibearugbulem OM, Ezeh JC, Ozioko HO, Anya UC
Page Numbers : 137-149
DOI : 10.36348/sjce.2020.v04i09.002
This work concentrated on the analysis of thick anisotropic rectangular plate through exact approach using third order shear deformation theory. Refined plate theory assumptions were relied upon to formulate the total potential energy functional. Displacement field, kinematic relations, constitutive relations and stress displacement relations were also obtained from the assumptions. Kinematic relations and Stress-displacement relations were substituted into the universal strain energy equation to formulate the strain energy equation. Total potential energy functional for the analysis of thick anisotropic rectangular plate was obtained by adding the external work and strain energy equation together. The total potential energy functional was differentiated with respect to the out plane deflection (w), shear deformation rotation in x direction (_x) and shear deformation rotation in y direction (_y). This yielded the governing equation and two compatibility equations of thick anisotropic rectangular plate. Third order polynomial shear deformation function which was derived by Ibearugbulem et al. was relied upon to obtain the displacement functions. From these displacement functions, the unique displacement functions for the SSSS plate boundary condition were determined. Also the stiffness coefficients were calculated for the SSSS plate boundary condition. The formulas for calculating the coefficients of the displacements were combined with elastic equations to determine the novel formulas which were used in calculating for displacements (u, v and w) and stresses (σ_RR,σ_QQ,τ_RQ,τ_RS and τ_QS) at various angle fiber orientation (0^0, 〖15〗^0, 〖30〗^0, 〖45〗^0, 〖60〗^0, 〖75〗^0 and 〖90〗^0) and various span to thickness ratio, α (5, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100). These formula were used to analyze typical anisotropic rectangular thick plates. The results obtained were shown on Tables 1, 2, 3, 4 and 5. These numerical results obtained showed some level of agreement with previous works by other scholars. Hence the developed method is recommended for analyzing thick rectangular anisotropic plates.
Original Research Article
Nov. 5, 2020
Analysis of SSSS and CCCC Thick Anisotropic Rectangular Plate Using Exact Displacement Function
J. C. Ezeh, O. M. Ibearugbulem, U. C. Anya, H. O. Ozioko
Page Numbers : 150-160
DOI : 10.36348/sjce.2020.v04i09.003
In this investigation, exact displacement functions were used to analyze thick anisotropic rectangular plates of two boundary conditions; simply supported on all edges (SSSS) and clamped on all edges (CCCC). Third order shear deformation model was employed in the formulation of the total potential energy functional for thick anisotropic rectangular plate. This total potential energy functional was reduced to the governing equation and compatibility equations for thick anisotropic plate. The governing equation and compatibility equations were solved to obtain the general displacement functions. By satisfying the boundary conditions for SSSS and CCCC plates their distinct displacement functions were obtained. These displacement functions were used to obtain the stiffness coefficients (k-values) for the plates. Minimizing the total potential energy functional with respect to the coefficients of the displacement functions gives the formulas for calculating the values of the coefficients. At this point, the displacements and stresses of the plates were calculated at various angles fiber orientations (0^0, 〖15〗^0, 〖30〗^0, 〖45〗^0, 〖60〗^0, 〖75〗^0 and 〖90〗^0) and various span-to-thickness ratios, α (5, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100). The results obtained were close to the results of other scholars.
Original Research Article
Oct. 18, 2020
Solution of Rectangular Plate on Winkler’s Elastic Foundation Using Characteristic Orthogonal Polynomials
E. I. Ogunjiofor
Page Numbers : 119-124
DOI : 10.36348/sjce.2020.v04i08.001
Plates supported on elastic foundations are found in many civil engineering applications. The analysis requires a critical understanding between the plate element and the foundation. The objective of this study is to come up with a better, simple, and easy analytical method that could be used for the analysis of all-round simply supported plate on Winkler's elastic foundation. The scope of the work includes static analysis of an isotropic simply supported rectangular plate resting on an elastic foundation carrying a uniformly distributed load. In this paper, characteristic orthogonal polynomials (COPs) shape functions for all-round simply supported rectangular plate on an elastic foundation were formulated by using Galerkin variational Energy method. The COPs shape functions formulation had been carried out by direct integration of the governing differential equation of the plate with those of elastic foundation using the Winkler model for the elastic foundation. The results obtained are very close to the results obtained by earlier research works that used different methods.
Original Research Article
Sept. 19, 2020
Effectiveness of Different Techniques on the Seismic Retrofitting of Existing RC Framed Buildings in Saudi Arabia
Ayed Eid Alluqmani
Page Numbers : 113-118
DOI : 10.36348/sjce.2020.v04i07.002
In this research, finite elements analysis is utilized, using SAP2000, to study the effectiveness of different techniques on the seismic retrofitting of existing reinforced concrete framed structures. The models are considered for reinforced concrete framed structures; and seismic evaluation is conducted. These models represent typical structures that were designed and constructed before and after the current Saudi Building Code, SBC-2007. The seismic evaluation was conducted using SAP2000 Program. This study focuses on performance based design of three multi-story RC framed buildings in Madinah, Saudi Arabia, subjecting them to monotonically increasing lateral forces with an invariant height wise distribution until the preset performance level (target displacement) is reached. Considering the deficiencies indicated in analysis, these buildings are redesigned by adopting retrofitting techniques such as shear wall, bracing and column strengthening. These techniques strengthen structures to reach the targeted performance level. The results indicate the effectiveness of each technique and how applicable it is to be used for seismic retrofitting of structures in Madinah, Saudi Arabia.
