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Using the ABAQUS software, this article presents a numerical investigation on the effects of various stud distributions on the behavior of composite beams. A total of 24 continuous 2-span composite beam samples with a span length of 1 m were examined (concrete slab at the top and steel I-section at the bottom). The concrete slab used is made of a reactive powder concrete with a compressive strength of 100.29 MPa. The total depth of each sample was 0.220 m. The samples were separated into four groups. The first group involved 6 specimens with shear connectors distributed into 2 rows with different distances (65, 85, 105, 150, 200, and 250 mm). The second group had the same spacing of shear connectors as the first group except that the shear connectors were distributed with one row along the longitudinal axis. The third group consisted of six specimens with single and double shear connectors distributed along the longitudinal axis. The fourth group included six specimens with one row of shear connectors arranged in a staggered distribution along the longitudinal axis. Results show that the optimum spacing was 105 mm in all groups and the deflection in group four fluctuated up and down due to the non-symmetrical distribution of the shear connectors.

Geotextile reinforcement techniques have been widely used in paving works around the world and have proven to be effective in improving pavement performance. This study has focused on using different positions and numbers of geotextile reinforcement sheets between the layers of flexible pavement for rutting reduction. Fitting depth was measured in the field at seven constructed sections of the pavement of the road model. Each section has been strengthened with different reinforcement approaches. All road sections were subjected to a maximum load repetition of 10,000 cycles. The results indicate that using three layers of geotextile beneath each course of the designed road pavement sections (surface, binder, and base) reduced rutting by 96%. Traffic benefit ratio (TBR) has been employed in this study to reveal the behavior of geotextile reinforcement in increasing the service life of the road. TBR values are the load cycling ratio between the reinforced and unreinforced section for the exact recorded rut depth, it has been found to be minimally equal to 4 for the case of using one layer of reinforcement at interface I, and that value keeps growing up for other reinforcement cases.

An experiment was conducted in the greenhouse of the Department of Biology / College of Science / University Mosul, where chickpea Cicer arietinum L planted in soil clay mixture with the plants exposed to three levels of salinity (I00,50,0.0)mmol / liter as well as spraying plants with four concentrations of salicylic acid (25,15,5,0.0) mg / liter, To know effect of these factors on growth and some of the physiological traits of chickpea plant, the results obtained in experiment were analyzed by using Complete Random Design C.R.D as a practical experiment, the results showed that the plants treated with salicylic acid superior in plant height, shoot and root dry weight, leaf area and the relative water content by (%19, 54.6, 33.9, 30.1, 57.3) respectively, compared to the untreated plants. There was also a significant decrease in all the above-mentioned traits when exposing the plant to salinity levels (100,50)mmol / L compared to plants not exposed to salinity. [ABSTRACT FROM AUTHOR]