The distress of moisture induced damage in flexible pavement received tremendous attention over the past decades. The harmful effects of this distress expand the deterioration of other known distresses such as rutting and fatigue cracking. This paper focused on the efficiency of using the waste material of demolished concrete to prepare asphalt mixtures that can withstand the effect of moisture in the pavement. For this purpose, different percentages of waste demolished concrete (0, 10, 20, 30, 50, 70 and 100) were embedded as a replacement for coarse aggregate to construct the base course. The optimum asphalt contents were determined depending on the Marshall method. Then after, two parameters were founded to evaluate the moisture susceptibility, namely: the tensile strength ratio (TSR) and the index of retained strength (IRS). To achieve this, the indirect tensile strength test and the compressive test were performed on different fabricated specimens. The results show that mixtures with a higher percentage of demolished concrete possess higher optimum asphalt content as this parameter increased from 3.9 % for control mixture to 4.5 % for mixture with coarse aggregate that fully replaced by demolished concrete. This work indicated that optimum percent of waste demolished concrete that can be utilized in the asphalt mixtures is 30 %, whereas this percent recorded higher value of increased increments for TSR and IRS by 10.6 % and 7.9 % respectively.
Compaction of triticale grain with three moisture contents (8%, 12%, and 16% wet basis) was measured at five applied pressures (0, 7, 14, 34, and 55 kPa). Bulk density increased with increasing pressure for all moisture contents and was significantly (p < 0.0001) dependent on both moisture content and applied pressure. A Verhulst logistic equation was found to model the changes in bulk density of triticale grain with R2 of 0.986. The model showed similar beha
سمير خلف فياض * و محسن طالب د.نوال عزت عبد اللطيف*, مجلة الهندسة والتكنولوجيا, 2010
This study involves adding nano materials and interaction with cement mortar behavior for several mortar samples under variable curing time with constant water to cement ratio (W/C = 0.5). The effects of adding nano materials on the microstructure of cement mortar were studied by (Scanning Electronic Microscopy (SEM) and X-Ray (for samples at different curing time 28 and 91 days. Small ratio replacements of nano particles (SiO2 or Al2O3) were added to Ordinary Portland Cement (OPC) type (I). The percentage of nano materials additives replacement by weight of ordinary Portland cement includes (1, 2, 3, 4 and 5%) for both types of nano materials with constant (W/C) ratio, also the amount of the fin
... Show MoreFind goal to detect educational and technical staffing of style fiction in book reading school materials so determine the current research on the specific book reading in fourth grade of primary for the academic year 2014 issued by the Ministry of Education / Republic Iraq stories. Come in the importance of research to draw attention to the best of these stories and strengthened, and the negative deny it and claim his deportation in order to protect the thought of the learner, and the study may contribute to the development of some frameworks to write a story appropriate for elementary school. This McCann within the first chapter The second chapter included the theoretical framework has been contained on two main sections included the co
... Show MoreThe present work aimed to study the efficiency of thermal osmosis process for recovery of water from organic wastewater solution and study the factors affecting the performance of the osmosis cell. The driving force in the thermo osmosis cell is provided by a difference in temperature across the membrane sides between the draw and feed solution. In this research used a cellulose triacetate (CTA), as flat sheet membranes for treatment of organic wastewater under orientation membrane of active layer facing feed solution (FS) and draw solution (DS) is placed against the support layer. The organic materials were phenol, toluene, xylene and BTX (benzene, toluene, and xylene) used as feed solution. The osmotic agent in draw solution was
... Show MoreThis study explores the role of nanomaterials in the performance of asphalt binders and mixtures. Two commonly available nanomaterials, i.e., nanosilica (NS) and nanoalumina (NA), were used at contents of 0%, 2%, 4%, 6%, and 8% by weight of asphalt binder. A set of experiments was carried out at the binder level to investigate properties such as penetration, softening point, aging-related mass loss, nanomaterial dispersion (storage stability), and workability (rotational viscosity). In addition, the suitability of NS and NS was also assessed through the testing of nanomodified asphalt mixtures, which focused on Marshall properties, the resilient modulus, moisture susceptibility, permanent deformation, and fatigue resistance. The findings in
... Show MoreThe study presents the test results of stabilizing gypseous soil embankment obtained from
Al- Faluja university Campus at Al-Ramady province. The laboratory investigation was divided
into three phases, The physical and chemical properties, the optimum liquid asphalt (emulsion)
requirements (which are manufactured in Iraq) were determined by using one dimensional
unconfined compression strength test.in the first phase , The optimum fluid content was 11%
(6% of emulsion with 5% water content).. At phase two, the effect of Aeration technique was
investigated using both direct shear and permeability test. At phase three for the case of static
load , the pure soil embankment model under dry test condition was investigated
A new pavement technology has been developed in Highway engineering: asphalt pavement production is less susceptible to oxidation and the consequent damages. The warm mix asphalt (WMA) is produced at a temperature of about (10-40) oC lower than the hot asphalt paving. This is done using one of the methods of producing a WMA. Although WMA's performance is rather good, according to previous studies, as it is less susceptible to oxidation, it is possible to modify some of its properties using different materials, including polymers. Waste tires of vehicles are one of the types of polymers because of their flexible properties. The production of HMA, WMA, and WMA modified with proportions of (1, 1.5, and 2%) of rub
... Show MoreAbstract: This research was performed to study the effect of some amino acids and vitamins on the growth of bacteria Staphylococcus aureas and its sensitivity against UV light. The results showed low inhibition in bacterial growth because amino acids repairs the damges caused by UV light. Besides the effect of two groups of antibiotics (β-lactame and tetracycline) on the growth of S. aureus and the possible interference of amino acids and vitamins in the activity of the antibiotics against this bacteria in the presence of UV light were studied. The result show increase in the sensitivity towards these antibiotics and provided protection against the antibiotics.
This experiment was conducted in field of Agricultured Department Baquba/Diyala province in spring season 2011 to study the water stress by using foliar application concentrations of each Proline acid and Abscisic acid on proline content , ABA content , chlorophyll content, protein conten and water content in leaves of Maize( cultivar, Buhooth 106). The layout of the experiments was Split- split plot design as RCBD with three replicates. The three concentrations of spraying Proline acid levels ( 0 , 150 , 200 mg Proline .l-1 ) Three Abscisic acid levels ( 0 , 15 , 20 mgABA.l-1. ) and three periods of irrigation after(25, 50, 75%) of available water . Folair fertilizer were applied at three
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