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OBJECTIVE: To assses the association of H -pylori infection and recurrent abdominaal pain in children.Material and methods: The association of H -pylori infection and recurrent abdominal pain were studied in 44 children, aged 4-12 yrs. Using stool antigen test (HpSA) and serlogical identification of IgG by ELISA. 26 children without RAP were subject for HP identification also as acontrol group. Cases with specific causes for abdominal pain were excluded from the study.Information about demographic ,socioeconomic, envirometal living state were obtained to lable possible risk factors. High percentage (85%) of HpSA and sero positive children with abdominal pain had complete symptomatic relief after eradication of organism.Results: High percentage (64%) of children with recurrent abdominal pain show positivite result for H-pylori stool antigen test and IgG identification in comporism with asymptometc children (46%).Conclusion: There is apossible association of H –pylori infection and recurrent abdominaal pain in children and these patients should be consider for H –pylori eradication.

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: One of today’s most important societal concepts is sustainability. This ideal can be described as meeting the needs of the present without compromising the ability of future generations to meet their own needs. Hot mix asphalt (HMA) recycling produces an eco-friendly mixture known as Reclaimed Asphalt Pavement (RAP). The main objective of this paper is to determine the effect of RAP percentage usage on the characteristics and properties of asphalt concrete mixtures. In this paper, a detailed laboratory study is carried out by preparing asphalt mixtures specimens using aggregate from Al-Nibaay quarry, (40-50) grade asphalt from dourah refinery and four different percentages of RAP material: 0%, 5%, 10%, and 15%. The experimental testing program included four point repeated load and Indirect Tensile Strength tests. The experimental results indicate that, that the inclusion of RAP materials improves fatigue properties of HMA mixtures; fatigue life (Nf (at RAP content of (15 %) increases by (157.1%), (100%), and (150%) at testing temperature 25, 10, and 40°C respectively. Based on the modified Lottman test, it was found that HMA with RAP additive had a high resistance to moisture damage through increasing the indirect tensile strength of such mixtures. The results of four point repeated load test and IDT test indicate that the amount of new binder that needs to be added to the RAP mixture can be reduced without significant effects on the quality of the produced mix.

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The technique of cold recycling of asphalt pavement materials for road construction is widely used in the world. Different types of locally available stabilizing additives and/or agents were used to find the most suitable one from the point of view of strength, economy and environment. Cubic molds of (10) cm is used in the laboratory to prepare samples of the stabilized rap materials. The effect of curing mode (effect of water absorption) was studied from strength point of view. Increasing bricks sand in the stabilized RAP materials increase the compression strength because of filling the spaces. A brick sand increasing reduces the absorption in case of cement stabilizing while with lime increases the absorption. Dynamic modulus of elasticity decreases with bricks sand increasing. Cement ratio more than 5% alone or more than 3% with lime is recommended to use, lime stabilizing ratio not exceed 10%.

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The objective of the present paper is to examine the effect of Recycled Asphalt Pavement (RAP) on marshall properties and indirect tensile strength of HMA through experimental investigation. A mixture with 0% RAP was used as a control mix to evaluate the properties of mixes with 5%, 10%, and 15% RAP. One type of RAP was brought from Bab Al-moadam’s road in Baghdad for this purpose. The experimental testing program included Marshall and Indirect Tensile Strength tests. The results indicated that the bulk density, flow and VFA increase with the increasing of the percentage of RAP, while increasing in RAP results decreases in VTM and VMA values. Furthermore, the stability is changed from 10.1 kN for the control mix to12, 13.6 and 11.7 kN for mixes with 5%, 10% and 15% RAP respectively. The results reveal that the inclusion of RAP into HMA mixtures increases the indirect tensile strength and decreases the values of ITS with the increasing of the test temperature. The results also indicated that increasing the percentage of RAP produces an increasing in temperature susceptibility value. The results of marshall properties and IDT test indicate that the amount of new binder that needs to be added to the RAP mixture can be reduced without significant effects on the quality of the produced mix.

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Nowadays, reclaimed asphalt pavement is used as hot mix asphalt (HMA) because it has economic and environmental benefits. As an attempt to preserve aggregate resources and save money, this study was done. To evaluate the characteristics of the RAP aggregate, many tests were done that include gradation, specific gravity, Coarse Aggregate Angularity (CAA), Flat and Elongation (F&E), Los Angeles Abrasion (LA), and impact test. Three types of additive materials, which were SBS, CR, and PP, mixed with the reclaimed asphalt blends with three different percentages of 3%, 5%, and 7%. The conventional asphalt binder tests were done for the aged and reclaimed binders. As the percentage of the additive materials increased, the penetration and ductility of the asphalt binder decreased. The elastic recovery of the blends was increased from approximately 7% to 80% when different percentages of SBS additive were used. As the percentage of the additive materials increased, the softening points of the blend increased. The specific gravities of the reclaimed blends were not changed significantly after adding additives. The flash and fire point temperatures increased when the percent of PP additive material was increased to the blends; however, the flash and fire point temperatures decreased when the percent of the SBS and CR additive materials increased. Based on the standard deviation of the RAP asphalt contents, the mixture blend was selected to be 40% RAP and 60% new material. The aged RAP binder was blended with a soft grade virgin asphalt binder that was 60/70 grade. The procedure of Superpave design mixtures was done to find optimum asphalt content and knowing the effects additives on moisture sensitivity of the mixtures. Adding additive materials benefits the reclaimed mixtures regarding moisture sensitivity. The most beneficial effects of additives on moisture sensitivity of the reclaimed mixtures were 7% SBS, 3% CR, and 5% PP obtaining the ITSR of 99.71%, 97.1%, and 90.7%, respectively. The selected most beneficial blends of the reclaimed asphalt binder with additives were further analyzed using Superpave performance grade tests. The additive materials changed the PG of the blended reclaimed binder with no additive materials from 64 -22 °C to PG of over 88-22 °C for 7% SBS, PG of 76-28 °C for 3% CR, and PG of 82-16 °C for 5% PP. It was recommended to use 7% of SBS in the reclaimed asphalt mixtures for hot climates, and 3% of CR for cold climate conditions.

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