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Hydraulic steel gates are commonly used for their superior characteristics in carrying both tensile and compressive stresses. Corrosion, operation, and maintenance costs make it essential to search for suitable alternatives. In this research, Glass Fiber Reinforced Polymers (GFRP) were investigated as a promising choice that can be used to resist flexure stresses as in case of hydraulic gates. Firstly, typical mechanical tests were conducted on nine specimens made of pure steel beams, four ribbed steel beams, twenty-four specimens of pure GFRP beams, along with four combined specimens from both materials. GFRP beams were also used in cooperation with polyester cemented sand to form a sandwich like beam. It was concluded that beams from GFRP achieved similar flexural capacity of steel beams of slimmer thickness. Combinations of steel and GFRP show satisfactory results while maintaining member ductility. The load capacity of the strengthened steel beams increased by 80% to 97% compared to specimens made from steel only. Failure modes for all specimens were introduced and compared. Moreover, numerical investigation was conducted using ABAQUS nonlinear module. Finite element models for three small gates of dimensions (1.0 x 1.0 m). A steel gate of thickness 14mm, Pure GFRP gates of thicknesses 29mm and 45mm were simulated. The 29mm GFRP gate was able to bear almost the same loads of the steel gate with equivalent deflection. Finally, it can be concluded that for small-scale hydraulic gates, GFRP can effectively be used as a suitable alternative for steel gates after setting limitations for failure strains. [ABSTRACT FROM AUTHOR]

Using of Reclaimed Asphalt Pavement (RAP) has been become indispensable in most of the world nations as for its many benefits as significant cost savings and provide environmental benefits. Many factors such as virgin materials, binder content, availability of RAP, viscosity of binder and extent of deterioration had important role in effecting on Optimum percentage of RAP. In this study, effect of using RAP on the asphalt mixture properties and the its optimum ratio was determined to achieve the objective of the study. The glass fiber (GS) was used as additives to improve the asphalt mixture. It has been observed from the previous researches that the optimum percentage of reclaimed asphalt use is not determiner and is disagreed from project to project. So, different percentages of RAP was (25%, 50%, 75%, 100%) by weight of aggregate were added as well as using the additive GS at optimum bitumen content. The study is revealed that untreated 100% RAP materials are not good as a bituminous mix. and was showed that mix prepared with 25% RAP gave nearly the same physical and strength parameters as virgin bituminous mix. From results of study, the use of RAP until (%50) as a maximum percentage in unmodified asphalt mixture course sustained good results. To achieve better performance, the percentage of 25% RAP was used with percentage of 0.26% GS. This mix achieved the specification requirements and ensured the degree of better performance for paving. The economical evaluation of using percentage of 25% RAP with percentage of 0.26% GS was also studied. The results indicated that, about 21% of the cost was saved. [ABSTRACT FROM AUTHOR]

Expansive soils refers to a particular type of soils - almost clayey soils - that expand as they absorb water and shrink when they dry out. The process of swelling generates pressures that can cause lifting, or heaving of structures whilst shrinkage process can cause differential settlement. A large number of buildings and roads are placed on such soil and exposed to the danger from this swelling and shrinkage processes. In order to avoid the previous mentioned risk from the expansive soil, a technique of soil stabilization should be made for this type of soil to enhance some of its properties. In this study, we experimentally treated a particular type of an expansive soil as a subgrade material by adding three different types of chemical additives which are (Addicrete P), (Addibond 65) and (Glass Fibers) at different mixing ratios 2, 4, 6% to maintain an enhanced subgrade layer according to its swelling and bearing behavior. A series of laboratory-coded tests were conducted on the native soil. Tests are Atterberge limits, Modified proctor, and California bearing ratio test. The same tests are also conducted on each soil-additive mixed sample. Results showed that there is a tendency from the soil to stabilize by these additives. California bearing ratio was increased from 4.7% to 8.05% and the expansion after the 96 hours soaking time was eliminated from 4.95 millimeters to 0.35 millimeter. This is considered the best effect and was a result from mixing the native soil with a percent of 6% Addicrete P. [ABSTRACT FROM AUTHOR]