KUFA JOURNAL OF ENGINEERING

The main objective of this study is to investigate the effect of adding hydrated lime on themoisture damage resistance of asphalt concrete mixtures. In this study two samples of asphalt concrete mixture were prepared, the first sample represent control mixture, and the second sample contain hydrated lime with rate (0.5, 1, 1.5, 2.0, 2.5%) by thetotal weight of aggregate. The properties of control mixture and Lime-asphalt concrete mixture were evaluated by Marshall tests results, Indirect Tensile Strength (ITS) results, and retained Marshall Stability (RMS) test results. The results for these tests indicated improvement in mixture proprieties, increased resistance of asphalt concrete against moisture damage, and reduced effect of water on the properties of asphalt concrete. As a final result, the use of (2%) hydrated lime enhanced asphalt concreteproperties and produce durable mixtures for highway construction.

A nonlinear finite element study has been conducted to investigate the effectiveness of strengthening RC beams with pre-stressedNSM CFRP rods in enhancing the flexural strength ofthe beams. Four beams have been considered. One acted as control to simulate an existing structural member. The other beams were strengthened with non-pre-stressed CFRP rod (0% pre-stressed), and pre-stressed CFRP rod (40%, or 60% pre-stressed of the CFRP rod tensile strength). The results of analysis showed that strengthening of the RC beams with non pre-stressed NSM CFRP rods improved both of the flexural capacity and deflection response. Increases in the cracking, yield and ultimate load of 17%, 20% and 48% were achieved. With a pre-stress level of 40%, an enhancement of 117%, 53% and 80% respectively over that of the control beam. For the beam strengthened with pre-stress level of 60%, more enhancements in response were achieved in term of the cracking and yield loads, but a slight reduction in ultimate loads (compared with lower level of pre-stress). Increments up to 160% and 67% in the cracking and yield load respectively. While 77% in ultimate load over that of the control beam were obtained.

This work deals with an experimental and computational study was carried out on the structural behavior of circular concrete filled aluminum tubular columns subjected to increasing axial load. Twenty four specimens were tested to investigate the effect of diameter, D/t ratio and slenderness ratio of a aluminum tube on the load carrying capacity of the concrete filled tubular columns. Diameter to wall thickness ratio between 23.3 ≤ D/t ≤ 47.8, and the length to tube diameter ratio of 3 ≤ L/D ≤ 10 was investigated. The structural performance of the concrete-filled aluminum tube columns (CFTa) was investigated using constant concrete cylinder strengths of 24.2 MPa.The main purpose of the computational study aimed to investigate the potential of using fuzzy inference system (FIS) to predict the strength of the composite columns. Fuzzy inference system (FIS) model has been provided to be very effective in predicting the ultimate strength of aluminum-concrete composite columns. The average values of ratios of experimental to predicted ultimate loads are 1.001 forthe Sugeno FIS model. The circular hollow section tubes were fabricated by extrusion using 6061-T6 heat-treated aluminum alloy

For more than five decades, car-following models have been developed based on different theoretical backgrounds and conditions. The importance of these models belongs to their representation of longitudinal movement for any simulation model. Therefore, the accuracy of the car-following model is still the core of strength of any simulation model. For the purpose of this study, a hybrid car-following model has been developed to represent “go and stop” conditions. These conditions mostly occur in a weaving section. This model has been developed as a corner stone for a microscopic simulation model of representation of driver behaviour at a weaving section. A new condition that improves a driver behaviour in a situation at which the driver should not accelerate under specific condition as approaching from decelerated leading vehicle. Some assumptions of this model have been adopted from the CARSIMmodel. After developing this model using Visual Compact Fortran (version 6.5), the developed model has been calibrated with a set of field data from Germany. The results show that this model is more reasonable than other models such as Paramics, VISSIM, AIMSUNand CARSIMusing the same set of data. This model show significantly improvement in representing the reality than the others.

A weak clayey silt soils from Garmmat Ali and a sandy soil from AL-Nashoa region were used from different sites and depths and mixed with (0.2%,0.4%,0.6 w/W) of Novolac polymer with (2%,4%,6% w/W) of Cement to know the profitable amount of Novolac, and improving some of engineering properties of the soils that include: the plasticity and compacting. A noticeable improvement in the plasticity of these clayey soils as result of adding a mixture by the rise in their plastic limit, dry densities, lowering in their optimum moisture contents, and increase in tensile strengths as compared with crude soils. There are also an improve in treated sandy soil properties. The cost of using this polymer as a soil binder was reduced by about 50% as compared to the usual practice which involve removing the clayey silt soils and replace them by sand or other materials.

In this paper, two quantization matrices are proposed that is suitable to compress medical images using framelet transform. Also two algorithms are suggested to compress medical images. One of them is used for grayscale and color medical images while the second is used for grayscale medical images only. It is found that the first proposed quantization matrix is better than the second in terms of Peak Signal to Noise Ratio (PSNR). While the second proposed quantization matrix is faster than the first. The work suggested in this paper is compared with wavelet and multiwavelet based algorithms and other previously related works and it is found that the quantization matrices proposed are most suitable for compression medical images with framelet transform and framelet transform is the best compression method for medical images.

The research presents an experimental study of the interaction between cavity and adjacent hydraulic structure in sandy soil. Experimental studies were performed to investigate the effects of the different factors (such as cavity locations and size of the cavity) on the quantity of the seepage, steady time and flow line . Different sizes and locations of the cavity are investigated in flow media. It was found the diameter of the cavity is an important parameter.Dimensional analysis techniques and (STATISTICA) program were used for finding new formula with based on the experimental data, which are used to compute the quantity of seepage.This formula was derived to predict the quantity of the seepage in terms of spacing between the sheet pile wall and center of the cavity in upstream and downstream zones, spacing between water level and center of the cavity in upstream and downstream zones.

 Artificial Neural Networks (ANNs), with three layers feed- forward network of sigmoid hidden neurons and linear output neurons are performed for predicting Tigris River flow in Baghdad City, middle of Iraq. The network is trained with Levenberg-Marquradt back-propagation algorithm. The number of hidden neurons is estimated according to trial and error procedure. The best model is selected according to trial and error procedure based on root mean square error and coefficient of correlation. The selected model is used to predicate the river discharge for one, two, and three months ahead. Results indicate that the ANNs with Levenberg-Marquradt back-propagation algorithm are a powerful tool for forecasting the river discharge for short term duration. But this ability begins to decrease when increasing the period of forecasting.

The utilization of recycled aggregates can minimize environmental impact and slow the huge consumption of natural resources used for concrete applications. However, recycled aggregates are not suitable for use in the production of High Performance Concrete (HPC) due to their relatively high absorption capacity, unstable properties and recycled aggregates' weaker strength. Such inadequacies can be overcome through carefully examining the characteristics of recycled aggregates and then adopting proper mixture proportions. The mechanical properties of self compacting concrete (SCC) are well understood. Butthere are no scientific investigations available on the influence of a heat water treatment on the properties of SCC produced from recycle aggregate. To evaluated the influence on the mechanical properties five mixture were designed, SCC without recycled concrete aggregateand four ( SCC with 25% recycled concrete aggregate SCC with 50% recycled concrete aggregate,SCC with 75% recycled concrete aggregateand SCC with 100% recycled concrete aggregate) and exposed to heat of treatment water with different temperatures ( 40-100 )Cₒ. It has been found that there is possible to produce SCC with various percentage of recycled concrete by using a suitable dosage of SP which was a major component in producing good quality RCA( recycled concrete aggregate ). Also found an influence of the composition of the concrete, especially the quantity of recycle aggregate and heat of curing water on mechanical properties of concrete (compressive strength, splitting tensile strength and flexural strength).

Expansive soils are distributed in many regions in world. (including Iraq),particularly in semiarid regions with alternating wet and dry seasons. Therefore, it is necessary to study the geotechnical properties of such soils due to the possible large damage of structures founded and constructed on this soil. The soil used in this research is from Abu-Ghreab site.This paper reports the outcome of an investigation into the effect of cement on geotechnical properties of expansive soil, to ascertain its suitability for use as a modifier or stabilizer in the treatment of the soil. Classification, consistency indices, specific gravity, compaction, direct shear, and swell percentage and swell pressure tests, were conducted on specimens of expansive soil. Results of tests showed that the soil was a CH soil, according to the USCSclassification system.Liquid limit , plastic limit and plasticity index are reduced by adding 8% of cement , at optimum moisture content the maximum dry density value increase with increase the percentage of cement adding to the expensive soil and conducting direct shear test, an obvious increase is noticed in the amounts of cohesion (C) and internal friction angle (Ø) .While swell percentage decreases by adding cement and while the swell pressure decreases to the half of its original values.

The industrial using of wells water in Iraq for buildings air conditioning are unknown or limited. So to state the benefits of this natural source an experimental and theoretical study in this field was established inorder to be funded by ministry of higher education to do larger cooling systems. The study concern on the ground water found in Najaf Institute which locate at Najaf sea south of Iraq. As a starting step the climate conditions was studied to determine the temperatures in a different periods of the year. The results proofed the benefits of temperature difference between the well water and the studying halls.Two studying halls were chosen, one of them used an air conditioner(capacity 2 ton) ,the other used well water cooling system. The temperature difference between two halls were taken ,as well as, the electricity consuming. A theoretical –experimental procedure was used to make design of cooling system. The heat load for the hall ,temperatures and velocity of water and air were measured.