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.

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Tuned mass dampers (TMD's) are passive energy devices used to reduce undesired vibrations in a number of structures or structural components such as industrial buildings, floor systems, and others. There have been few studies on the effectiveness of TMD's in reducing earthquake effects in low rise and medium rise buildings. This paper investigates the effectiveness of tuned mass dampers on the response of low rise and medium rise buildings under earthquake ground motions. Numerical integration methods were used to solve the systems of coupled equations of motion. Response parameters include roof displacements, base shears, and story drifts. Results from this analysis showed that the TMD can be effective in reducing drifts and base shears in low and medium rise buildings. The reduction was dependent on the TMD properties and location and optimum properties of the damper. A reduction of about 30% was observed in roof displacements for a mass ratio of 10% of the modal mass. A 25% reduction in base shear was also observed for certain cases despite the overall increase of mass of the system. However, this reduction should be interpreted taking into consideration the magnitude of drifts and base shears to justify the use of TMD's

The use of integral abutments in bridges goes back many years to the late 1930’s in the United States. Over the years, integral bridges became more popular as more and more states built those bridges and more engineers became familiar with their design and construction. These bridges are being built in Europe since the 1980’s. An integral abutment bridge acts as a frame structure with a continuity connection between the superstructure and the substructure. The substructure is typically an integral cap supported on single row of piles that provides flexibility to accommodate thermal loads and displacements. The main advantage of integral abutment bridges is that they are built without expansion joints which eliminates maintenance costs and reduces construction costs. Because of the interaction between the soil and the integral abutment under the applied loads and the cyclic nature of thermal loads, the analysis and design of integral abutment bridges can be, in some cases, challenging especially when the designs falls outside the geometrical limits set by existing standards. This overview focus on field performance data reported in the literature and interpretation of this data. IT also highlights the needs for more test data during construction and for long term performance under cyclic thermal movements. Deck replacement requirements in integral abutments were investigated using analytical models and recommendations for deck replacement preparations are provided.