Granite Powder (GP) and Iron Powder (IP) are industrial byproducts generated from the granite polishing and milling industry in powder form respectively. These byproducts are left largely unused and are hazardous materials to human health because they are airborne and can be easily inhaled. An experimental investigation has been carried out to explore the possibility of using the granite powder and iron powder as a partial replacement of sand in concrete. Twenty cubes and ten beams of concrete with GP and twenty cubes and ten beams of concrete with IP were prepared and tested. The percentages of GP and IP added to replace sand were 5%, 10%, 15%, and 20% of the sand by weight. It was observed that substitution of 10% of sand by weight with granite powder in concrete was the most effective in increasing the compressive and flexural strength compared to other ratios. The test resulted showed that for 10% ratio of GP in concrete, the increase in the compressive strength was about 30% compared to normal concrete.Similar results were also observed for the flexure. It was also observed that substitution of up to 20% of sand by weight with iron powder in concrete resulted in an increase in compressive and flexural strength of the concrete.

No abstract

This paper presents an investigation of Islamic arch forms and structural performance based on its geometrical formation. Arch form depends on several interrelated variables such arc angles, the ratio of arc radius to arc span, and the height of the arch. These variables are controlled in Islamic architecture by the geometry. This paper provides insights for the geometric design of Islamic arches and outlines its structural analysis under different load cases. A parametric study of the buckling behavior of arches for several load cases, horizontal thrust, and bending moment will be analyzed. This paper aims to provide an understanding of the structural concepts of the arch form in Islamic architecture based on the significance of geometry in construction of Islamic arches. Arches described by geometry and proportions, plays a crucial role in the composition and structure of the arch form. Typically design parameters are based on estimating force vectors to determine arch shape, assuming that they represent the architecture properly and are constant. To describe arch architecture in more detail and compare geometrical and non-geometrical states, geometric approach was validated. Arch forms are constructed from historical sections, based on geometric language, as well as the shape of the arch. The proposed approach may help to identify functional structural concepts within the arch, with homogeneous architectural geometric properties. The related results are discussed regarding the parameters essential for structural arch modeling and challenge aesthetic parameters of the arch-model.

This research aimed at tracking and investigating the evolution and development of domes construction, design, sizes, shapes, used materials, and functions of the domes during the different eras of the Islamic architecture. To achieve the research's objectives, the study used the descriptive, analytical and historical methods to deepen and enriching understanding the value and the aesthetic features of the domes, and the used instructional methods, how they were developed from bricks, stones, to reinforced concreted covering wider spans of the mosque to provide good view to the Mihrab and to see the speaker. In addition, the research used a case study dome of Mosque King Abdullah Ben Al-Hussein to learn useful lessons from some of the tumbles in the construction of the dome during the construction and after the usage, including sound distortion and echo resulting from lack of adherence with the golden percentage, between the dome's height and width of the mosque. Finally, the research based on the review of the previous domes construction introducing some recommendations to the designers of the domes, the most important to sustain the beauty and significance of the domes without imitation of other domes rather through carefully study the internal and external constraints to reach the optimal result at cost effectiveness. Introduction:This research aims to shed light on the evolution and development of the domes in Islamic architecture, and to know forms of the domes in their appropriate structural position, either in the religious buildings or housing building. This requires following-up the historical buildings that have been found from the excavations in the previous eras and known civilizations which our Arabic and Islamic regions are rich of them. The Islamic domes are influenced by the architecture of these civilizations and nations, but at the end they took special feature specific to them. Forms and decorations of the domes were multiple in the Islamic countries, either inside or outside the dome. Multiple geometrical and plants drawings were used, in addition to the Kuranic verses. The Islamic domes have reached high level of superiority from the structured and the architectural sides and became important constructional element in covering the religious buildings.

One of this theoretical study, parameters that affecting the ultimate load capacity of the axially loaded column are studied. The parameters such as compressive strength of concrete and steel reinforcement ratio.  Throughout study a different value of each factor will be assumed. Then the nominal load-carrying capacity of axially loaded column was calculated for these different factors parameters according using the simplified methods provided in (ACI-318- 14) building code requirement for structural concrete and Prokon Program. It is observed that increasing the compressive strength of concrete result in improving the ultimate load capacity. Using compressive strength of concrete more than 40MPa which results in increasing of (Pu) from (2362kN) to(5918KN) . On other hand The total area of longitudinal reinforcement bars (AST), and the gross area of concrete section (Ag) have a significant effects also on increasing of (Pu) value but not as (Fcʹ).