محمد عباس حسن الجميلي

Traffic congestion is one of the main problems in large urban cities. The evaluation of the performance of any traffic facility, such as basic freeway segments, merging sections and diverging sections, depends mainly on investigating the main relationships such as speed-flow and flow-occupancy. This study has focused on the fundamental relationships of traffic stream, including flow-speed, flow-density, speed-density (Greenshield relationships), headway-flow and flow-occupancy relationships. 24-hour data, each minute, from loop detectors has been adopted to produce the above mentioned relationships. Field data has been collected from two different sites in Manchester city in the UK. These are three-lane and four-lane sections. In some cases of the current data, the behaviour has been investigated under 1min, 5min and 15min periods to show the difference between various periods of data collection. The analysis of this data has revealed different behaviours at different sections for each lane. The main use of this data is to provide the critical values which are the basis for Intelligent Transportation System (ITS) applications, such as simulation models. This data could be used for the calibration and validation of simulation models, such as S-Paramics or VISSIM, as well as other developed models.

Porous asphalt mixture (PAM) is mainly applied to the surface drainage layer on high-speed trafficked highway pavements because it has many application advantages such as : noise reduction and safety during rainfall due to its open structure water is stored and moved horizontally within the layer which reduces splash and spray effects and thus increases the visibility of drivers during rainfall. On the other hand the major disadvantage of porous asphalt layers are low stiffness , high rutting and durability .The objective of this study was to compare the influence of two modifier types (styrene-butadiene-styrene [SBS] and propylene modifier [PP]) on a porous asphalt mixture performance . The PAM evaluation was based on air voids, asphalt flow drain down, and abrasion resistance at the mix design step. The mix performance has been investigated by permeability, moisture susceptibility, and rutting. The test results emphasized the importance of using the modifier in in minimizing the abrasion loss, reducing rutting and enhancing the durability of the PAC mixture. Porous asphalt mixtures prepared with 5 % SBS modifier were the most effective at increasing the abrasion resistance and reducing rutting

Two asphalt cements (PG76-22 and PMB PG76-22) and two aggregate gradations used in the construction of surface and base courses were selected to study their effect on the mixtures’ rutting behavior. A dynamic modulus and wheel tracking tests were performed to determine the rutting potential of asphalt mixtures at different temperature levels. The study revealed that modified asphalt cement (PMB PG76-22) with coarse aggregate gradation (base course) may offer more resistance to rutting than unmodified asphalt with coarse and/or fine aggregate gradation. ABAQUS version 6.14 software was used to estimate the rutting of modified and unmodified asphalt mixtures under various values of CBR for subgrade, complex modulus of asphalt mixtures, temperatures and repeated tire pressures. The goodness between rut depth obtained from wheel track and ABAQUS software were observed. The rut depth model has been developed by analyses of 336 ABAQUS software runs by using SPSS STATISTICS version 23 software.

The study investigated the physical and rheological properties of asphalt binder modified by polypropylene and cellulose materials. The tests were conducted in the study; conventional tests such as; penetration, softening point and ductility, and unconventional tests such as rotational viscosity and dynamic shear rheometer (DSR). From the conventional tests it found that the hardness of modified asphalt binder with the addition of polypropylene and cellulose materials up to 5%. As a result of increased the hardness the softening point of modified asphalt improved compared with base asphalt binder. The rheological property of modified binders enhanced at low temperatures and high temperatures, as the results of DSR test showed that the G* were improved. The addition of a different percentages of polypropylene and cellulose fibers to base binder had remarkable influence of resistant to permanent deformation (high temperatures rutting and low temperature fatigue).

The main goal of this study is to evaluate cold mixtures incorporating various percentages of reclaimed asphalt pavements (RAP) which is a typical sustainability technique to enhance the modern flexible pavement technology. The physical properties of RAP materials, new emulsion asphalt and new aggregate have been tested to evaluate the characteristics of these materials. Two mix design methods have been developed for control cold mix without RAP and recycled cold mixes containing 25 to 90 % of RAP by weight of total aggregate. First mix design depended indirect tensile strength as an indicative measure to determine optimum emulsion asphalt content while the second mix design method used Asphalt institute method (MS-14 and MS-21) . It found that Asphalt institute method required higher percent of optimum asphalt content than ITS method. The test results indicated that the recycled cold mixes containing high percent ofRAP (75 to 90 %) are superior to control cold mix in traffic loading resistance and moisture susceptibility.

Abstract-This paper shows the optimal design of reinforced concrete box culvert based on minimum cost (economical design). The Genetic Algorithms (GAs)is the proposed method to optimize the structure which used as a tools box in MATLAB software version 2011, and the results of these method were verified by using Sequential Quadratic Programming (SQP) method which also used as tool box in MATLAB software version 2011. The formulation of the problem includes 11 design variables: two geometrical, and 9 structural variables for the reinforcement set-up and the thickness of top, bottom, and the thickness of side walls. A parametric study was conducted to specify initial population and population size and concluded that the optimum results were obtain for initial population= [1.8 1.8 0.2 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.000232773728 0.000232773728], and population size=100.