Building demolition waste constitutes a major component of municipal solid waste in Kuwait. Over 90% of this waste is currently land-filled, causing extreme pressure on the available land-fill sites. At the same time, the sources of natural aggregates are almost depleted, and there is an increasing demand because of the increased construction and maintenance activities. This article presents the results of a technical feasibility study into meeting this need by recycling the aggregates obtained from building demolition waste for asphalt concrete. The Marshall test, the immersion compression test, the loss of stability test, and the wheel track test were performed to evaluate the asphalt concrete made with recycled aggregate. The results showed that the asphalt concrete produced using an aggregate of demolition waste met all the requirements of local specifications.

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This research ensured the effects of radius variation on fatigue – life of AA6061-T6 and annealed alloy, AA6061-O. Five different sizes of radius (1, 2, 4, 8, and 16) mm were studied using Neuber notch factor (Kf) instead of the theoretical stress concentration factor (Kt). The numerical modeling was adopted using ANSYS Workbench 15 to evaluate the radius size effectiveness on strain and stress distribution, while the experimental procedure carried out to determine the strain-life constants for analytical calculations. The results show that the reduction in the radius leads to increase stress, while the strain remains close to each other with the variations of radius for both alloys. The decrement in stress and strain values for annealed specimens were observed in comparison with base alloy. The transition life (NT) was decreased whenever the radius decreased in both alloys. The fatigue life of annealed specimens increased for all values of radius compared to the specimens without annealed. The comparison of the fatigue life between the experimental and numerical results shows that the experimental results have more than those obtained by numerical estimation and this indicated the validity of the numerical approach.

This research presents an experimental and numerical analysis to examine the thermal loading of the exhaust manifold of a multi-cylinder gasoline engine operating under steady-state conditions. The local skin temperatures and surface heat fluxes variation are focused throughout the external surface of the exhaust manifold. A 3D modeling and simulation are employed in the numerical analysis using Solidworks software for modeling and ANSYS software for simulation. The generated numerical results are in good agreement with the measured exit gas temperatures and skin temperatures experimentally.

The Iraqi houses flattening the roof by a concrete panel, and because of the panels on the top directly exposed to the solar radiation become unbearably hot and cold during the summer and winter. The traditional concrete panel components are cement, sand, and aggregate, which have a poor thermal property. The usage of materials with low thermal conductivity with no negative reflects on its mechanical properties gives good improvements to the thermal properties of the concrete panel. The practical part of this work was built on a multi-stage mixing plan. In the first stage the mixing ratio based on the ratios of the sand to cement. The second stage mixing ratios based on replacing the coarse aggregate quantities with the Alabaster aggregates, and the third stage the mixing ratios based on the replacement of wood ash instead of the sand. While the fourth stage mixing ratios based on decreasing the thermal conductivity and increasing mechanical properties by adding a multilayer of a plastic net. The result shows that using a concrete panel with components (cement, sand, coarse aggregate, wood ash, and Alabaster aggregates) with a mass ratio of (1:1:2:1:1) and 3-plastic layers, gives the best improvement of the thermal properties. Where, the thermal conductivity is reduced by 42% and the specific heat increased by 41.2% as compared to the traditional concrete panel mixing ratio, with mechanical properties are agreed with the Iraqi standards.