Variation of Jebel Aulia Reservoir levels along White Nile River causes wider variation of the wetted area. This adds to the challenges for the pumping water for irrigation. Historically, there was always the tendency to maintain high reservoir levels in favor of the upstream pumping stations. The aim of this study is to assess possible impacts of changing the operation rules of Jebel Aulia Reservoir. Water balance approach has been applied to investigate the existing and three modified operation policy. The evaluated parameters include duration of high reservoir levels preferred by pumping schemes, satisfaction of downstream water demands and area of flood plain agriculture (Guroof), evaporation and hydropower generation. Scenario 2 was found to be the best in obtaining high reservoir level and given the highest annual hydropower production. Scenario 3 was found to be the best in terms of evaporation losses and the downstream demands.

The least squares weighted residual method was used in this work to solve the boundary value problem (BVP) of an Euler column of length l fixed at x = 0, and pinned at x = l. Polynomial shape (spline) functions for Euler columns with fixedpinned ends were used to obtain one – and two parameter buckling shape functions in terms of unknown generalised parameters. The one and two parameter buckling shape functions were used to construct least squares weighted residual integral statements of the boundary value problem. The least squares weighted residual statements simplified the boundary value problem (BVP) to algebraic eigenvalue – eigenvector problems. The solution for non trivial cases yielded characteristic buckling equations which were solved to obtain the buckling loads. One parameter coordinate shape function yielded the critical load as Qcr = 21EI/l2, while the two parameter buckling shape function yielded Qcr = 20.34614EI/l2. One parameter least squares weighted residual solution yielded a relative error of 4 % while the two parameter least squares weighted residual solution yielded a relative error of 0.77% compared to the exact solution.

Kingdom of Saudi Arabia (KSA) is rapidly developing with the government's vision (Saudi 2030 Vision) of working towards a developed nation by the year 2030. Government have implemented various types of development such as schools, government offices, hospitals, factories and, housing schemes, etc. It also aims to implement green building designs thereby using a recyclable structural material for construction such as Steel is a positive step. The use of truss design, construction, erection and installation is very popular due to it conventional configurations and popularity within the industry for its long spanning and lightness. Nevertheless, its selection and optimum design still needs proper attention. This paper addresses a parametric study to analyze and design single-story industrial buildings located in Madinah City using structural analysis and design software SAP2000®. Standards of the Saudi Building Codes SBC are used for the design purpose. The basic data related to wind intensity; dead and live loadings are obtained from SBC301. The dimensions of the two industrial buildings are (20mx35m and 30mx60m) with single span of 20m and 30m. Two different types of trusses are used thus gave rise to four cases. The design is carried out for the maximum capacities (compression, tension and shearing) of structural members to guarantee the structural safety. The purpose of this study is to understand the design philosophy and to give useful recommendations for the optimal and safe design of trusses with minimization of construction cost and time savings of industrial buildings.

In this work, the Picard’s successive iteration method was used to solve the elastic buckling problem of Euler columns with pinned ends. The problem was represented by a second order ordinary differential equation in the deflection function subject to the boundary conditions at the pinned ends. The boundary value problem was expressed in integral form, and the Picard’s iteration scheme developed from the integral form. A suitable buckling shape function was used to obtain an initial approximation to the deflection, and the Picard’s iteration scheme used to obtain first, second and third iterations for the modal buckling functions through the use of corresponding boundary conditions. Corresponding Picard’s approximations for the first, second and third iterations of the critical buckling load were obtained as 1 2 ( ) 9 6 0 / . , cr P E I l  ( ) 2 2 9 8361 / . cr EI l  and ( ) 3 2 9 8657 / . . cr EI l  The errors in the first, second and third iterates of the critical buckling load were -2.732%, -0.339% and -0.040% respectively. The use of the exact buckling shape function in the Picard’s iteration scheme was found to result in the exact closed form solution for the critical buckling load.

The tension stiffening index is a critical factor which improved their effect on the torsional behavior of fibrous reinforced concrete beams which included the bond strength between the reinforcement and the concrete, and the amount of reinforcement indexes. Thus, this paper highlights the effect of the tension stiffening index on the torsional resistance of ultra-high performance fiber reinforced concrete (UHPFRC) beams under pure torsion. Therefore, four under-reinforced ultra-high performance fiber reinforced concrete beams were cast and tested under pure torsion which contains the fixed amount of longitudinal and transverse reinforcements, while the grade and the rib pattern on the surface of reinforcement have been changed. Test results verified that the torsional resistance, stiffness of the cracked section and the twisting angle were improved at the crack and peak loads due to a reduction in the tension stiffening index. However, the axial strains in transverse and longitudinal reinforcements.

This paper presents the results of systematic analysis of joints trends in the rock masses exposed in the stretch between Al-Rawnah and Al-Huriyah areas, northwest of Taiz city, Yemen, using Fabric-8 software technique. From the field investigations and structural relations between the various lithounits, the exposed rock masses in the study area are classified into four litho-tectonic units viz., from bottom to the top:1) basement rocks, 2) Amran limestone rocks, 3) Al-Tawillah sandstone rocks and 4) volcanic rocks. Results of the study indicate that the rock units of the study area are cut and deformed by NNW-SSE, NE-SW, WNW-ESE, N-S, and E-W trending joints. NNW-SSE and NE-SW trends are the most predominant trends influencing the rock units of the study area. The dominant and major NNW-SSE trend correlates to the direction of the maximum extensional stress associated with the Red Sea rift system, while the second one (NE-SW) is perturbed regional stress field related to the direction of the stress generated during the opening of the Gulf of Aden. The basement rocks are commonly affected by both vertical and conjugate joints. The conjugate joints are represented by X and Y types, although T and H types were also recognized. Amran limestone rocks are affected by subvertical joints in addition to asymmetric with symmetric joints of veins filled by calcite minerals. Orthogonal cross joins, conjugate joints, polygonal joints and exfoliation joints were documented in Al-Tawillah sandstone rocks. Columnar jointing, plumose structures, horsetail fractures, kink joints and exfoliation joints are commonly observed in the volcanic rocks. This study indicates that the fracture spacing, orientation and thickness of the rock mass and patterns of fractures are controlled by lithology and structural evolution of the study area.

The State of Qatar has been undergoing radical transformation, coordinated by the national development planning strategy, to realise the aims of Qatar National Vision 2030 (QNV-2030). Efforts towards sustainable urban growth and development have included the establishment of a new transportation system, as well as transitoriented developments (TODs), which significantly enhanced pedestrians‘ access to amenities and facilities, particularly during major events. This research study aims to develop alternative design strategies for public transit systems and land use amidst the larger challenge of urban metamorphosis focused on boosting sustainability by enhancing liveability. The Al Sadd district was selected as a case study due to (1) its significance as one of the oldest mixed-use districts in Qatar, with a significant role in the economic development of Doha; (2) its many layers, which have overlapped; and (3) its lack of heritage significance. Data, gathered from both primary and secondary sources, consisted of questionnaires, site visits, walk-through observations, focus groups and structured interviews. The use of these research methods facilitated the exploration of the physical forms and sociocultural characteristics of the area, enhancing understanding of the urban quality, and providing inputs for a strategy to enhance the urban sustainability and liveability of the district.