AbstractThere is no doubt that the type and properties of cement extremely affect the general properties of produced concrete .Cement is one of the main ingredients of cement past phase in concrete. In present study chemical and physical properties of four types of Portland cement available in Iraqi local market were studied ,these types as follow : two types of ordinary Portland cement Kubaisa (Iraqi cement) and Ismnta (Jordanian cement) and the others of sulfate resisting cement Torab alsabia (Lebanese cement ) and Al-qaim (Iraqi cement).Chemical analysis of the four types of cement were conducted in Baghdad central laboratory in National Center for Constructional Laboratories and Researches (NCCLR) and Al-qaim factory laboratory .The physical tests were conducted in the concrete laboratory of Al_anbar university-college of engineering including standard cement paste ,initial and final setting and compressive strength of cement mortars.The results indicate that the local cement (Kubaisa and Al-qaim) showed better performance than imported cement (Ismnta and Torab alsabia) in most tested chemical and physical properties .Kubaisa cement showed 34.1 % , 35.5 % higher compressive strength compared with Ismnta cement at 3 and 7 day respectively and lower loss on ignition and insoluble residue . The major compounds of Kubaisa cement were nearest to those in typical cement. For sulfate resisting cement , Al-qaim cement showed 13.3 % higher compressive strength at 7 day and lower percentage of C3A (1.95%) . Torab alsabia cement exceed the limits of Iraqi standard I.O.S No.5 1984.
The use of nanomaterials in asphalt binders has become a very promising approach to improve the performance of pavements under growing traffic and environmental load. This research focuses on the influence of zinc oxide (ZnO) nanoparticles on physical and rheological properties of asphalt binder. ZnO was added in dosages of 1%, 3%, 5% and 7% by binder weight in a high shear mixing process. The modified and control binders were tested for their physical properties (penetration, softening point, ductility, flash point and viscosity), Dynamic Shear Rheometer (DSR) tests for rutting and fatigue performance and Bending Beam Rheometer (BBR) testing for low temperature behaviour. The results showed that the addition of ZnO nanoparticles reduced penetration and increased softening point, flash point and viscosity, which indicated the improvement of stiffness and thermal stability. Ductility was not affected, which confirmed that flexibility was maintained. Rheological analysis revealed that rutting resistance was significantly improved and a 76.7% reduction in the fatigue factor was observed in intermediate temperatures, whereas BBR results revealed acceptable low-temperature performance. The Performance Grade (PG) of the binder was improved up to two grades in higher contents of ZnO without exceeding limits for workability or thermal cracking. These results show that ZnO nanoparticle is an efficient asphalt modifier that enhances thermal, mechanical and rheological properties and thus can be used in high performance pavements applications with a wide range of temperature.
The main objective of the present study is to maintain clear environment by using natural fibers that not cause pollution. Two types of Jute fibers as mat were used to produce ratting polyester composites after treating these fibers with Iraqi dolomite of 0.2, 0.5, 0.7, and 0.9 percentages % where, eight specimens were prepared. Manual casting used to prepared these specimens by using fibers of 2.8 mm diameter between two layers of Resin for all specimens. Mechanical properties tests includes creep, tensile, and hardness by Shore method where best results of creep and tensile strength reduction are given with 0.9% of Iraqi dolomite. Hardness proportional with concentration of dolomite. Physical properties tests includes color, yellowness of color, were the samples exposed to U.V of 254 nm short length wave for 150 hours. The Jute fibers affected the color while the dolomite effects were inconsiderable, also the absorption of acidic and base solutions were proportionate reversely with increasing of dolomite and fibers' mat percentage. In biological tests, the Fungus growth on composite body decreased with increasing dolomite percentage and no great lost of weight. The present study shown that the Jute fibers in the composite body and concentration of Iraqi dolomite improve the mechanical, physical, and biological properties of polyester Resin composites with Jute fibers.
This study is the second stage of the paper “Study the Effect of Rubber Silicon on Physical Properties of Asphalt Cement”. This study took the effect of additives on asphalt mixture performance. Asphalt mixture has been designed by Marshall method for determining the optimum asphalt content and geophysics properties of mix according to ASTM (D- 1559 ). Rubber silicon at different percentage (1%, 2%, 3% and 5%) was added to asphalt binder and three specimens of asphalt rubber silicon mixture (ARSM) are prepared and evaluating according to Marshall method. Diametric tensile creep test ASTM (D-1075) at 60 Co used to evaluating permanent deformation and modulus of elasticity for ARSM. The study shown that the Rubber-Silicon has more effects increasing the marshal stability, air voids, and reducing the flow and bulk density compared with the original mix.. Increase the flexibility properties of the mix and this appear from reducing the permeate deformation at test temperature (60C), the reduction percent is about (30 to 70)%
Abstract :- For improving the properties of asphaltic cement several materials such as sulfur, rubber, carbon black, polymers….etc. are used for this purposes. In this study low density Polyethylene (LDPE) used at different percentage (0%, 1%, 3%, 5% and 7%) by weight of the asphaltic cement and then the changes in the properties are evaluated by pentration test (ASTM D-5), softening point test (ASTM D-2398), and Kinematics viscosity test (ASTM D-2170). Temperature susceptibility was evaluated by using Penetration vescosity number ( P.V.N ). In addition to that stiffness modulus of asphalt cement was predectied by using van der pole’s nomograph. The study showed that the LDPE increase the hardening of asphalt cement at different percentage except at (1%), and decrease the susceptibility of asphaltic cement to temperature.
This research includes study the effect of fineness upon physical properties of cement mortar where use ordinary Portland cement with fineness (300 m2/kg) as reference mixture which denoted by symbol (M1), and then produce with flowing fineness (350,400,450 and 500 m2/kg) which denoted by ( M2, M3, M4, M5 ) respectively . The results of study show that increasing in fineness makes an increase in water quantity that requires for consistence of standard paste and the ratio of above mixes with reference mixture (2%,5%,7%,11%)respectively, although the increasing in density for all ages and increasing in compressive strength in early age, the increasing ratio in 3 days age was ( 45% , 50% , 60% , 70%)respectively .this increasing in fineness makes increasing in ratio of flow as compared with reference mix(16%, 25%, 50%, 66%) respectively