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Foamed asphalt technology has increasingly gained acceptance as an effective and economical soil improvement and stabilization technique, mainly because of its improved aggregate penetration, coating capabilities, and handling and compaction characteristics. This laboratory research program was carried out to investigate the feasible use of foamed asphalt technology in Saudi Arabia to improve the prevalent dune sands for possible use as a base or subbase material. Several variables were investigated to evaluate the relative improvement of dune sand as well as to permit the development of design procedures for the future use of foamed asphalt technology in the harsh climatic conditions of eastern Saudi Arabia. Statistical analysis of the results was employed to verify the effects of emulsified asphalt and foamed asphalt treatment, with and without the addition of Portland cement, on the strength characteristics of the treated mixes. The results displayed significant improvement in the performance of dune sand foamed asphalt mixes, as compared to that of the emulsified asphalt mixes.

In the past few decades most of the efforts were made to achieve minimum weight of the steel structures by satisfying all the design requirements imposed by various latest building codes and this idea lead towards the concept of pre-engineered steel buildings (PEB). In current research work, minimum weight buildings are targeted with simple fabrication process and easy erection to have maximum structural efficiency. Minimum weight of structure is proportional to the minimum cost and hence lowers seismic and gravitational forces. To achieve above mentioned objectives and to verify the suitability and applicability of concept of PEB, a sample steel industrial building is first analyzed and designed by using conventional steel hot rolled sections and then by using pre-engineered tapered and cold formed sections. Results of analysis were compared in terms of weight and response of structures which clearly indicated that PEB structures are of less weight and structurally more efficient than conventional steel structures.

Background: Reinforced concrete silos and bunkers are commonly used structures for large storage of different materials. These structures are highly vulnerable when subjected to intense seismic forces. Available guidelines for analysis and design of these structures require special design skills and code procedures. Objective: The current study is aimed to elaborate the design procedures from different sources to a unified method, which can be applied to a larger class of reinforced concrete silos. In this study, analysis and design procedures are summarized and presented in a simplified form to make sure the efficient practical design applications of reinforced concrete silos. Method: Four different cases of silo design based on the type and weight of stored material were considered for the study. For each case, the silo was designed using given design procedure and modeled using FEM-based computer package. All of the reinforced concrete silos were subjected to gravity, wind and seismic forces. Results: After performing the analysis and design of different silos, the bending moment, shear force and axial forces profiles were given for a sample silo. The results obtained from the proposed design procedure were compared with FEM values for different components of silos such as slab, wall and hopper. Conclusion: The comparison of tangential and longitudinal forces, bending moments, shear forces and reinforcement ratios of different parts of silos have shown a fair agreement with the FEM model results. It motivates to use the proposed design procedure for an efficient design of reinforced concrete silos.