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Fine aggregates used for concrete works in Sulaymaniyah city frequently fail to meet the standard requirements for gradation and fineness modulus in cement concrete. This paper aims to critically evaluate gradation, fineness modulus, and clay contents of various natural sands produced and used for concrete work in the region.  Sixteen field sand samples were collected from various sites in Darbandikhan (5 samples), Qalat Dizah (5 samples), Koysinjaq (5 samples), and Piramagroon (1 sample) confirming to ASTM D75. The field samples were parted into test specimens based on ASTM C702. Then, sieve analysis was carried out on the oven-dry test specimens in compliance with ASTM C136. The test results of fine aggregates were compared with American, British, and Iraqi specification standards using ASTM C33, BS 882, and IQS No. 45. It was revealed that only three sands satisfy the ASTM gradation limits while others do not comply and are on the coarser side. Also, eight samples meet the requirements recommended by BS 882, whereas five samples meet limits by IQS No. 45. It was found that only three sands have the fineness modulus within the ranges recommended by ACI 211.1 and ACI 211.4, while the others have high values. Furthermore, it was found that all sands include an allowable amount of finer particles passing sieve size 0.075 mm. In order to improve particle size distributions, it is recommended to use the blending method to obtain a suitable fine aggregate from two or more failed sands.

This paper is focused on light-weight aggregate concrete with wood particles and its issuesaccording to physical and thermal properties. The experimental work for the estimation of density, absorption and thermal conductivity of light-weight wood-particles aggregate concrete is presented. Wide range of wood-particles percentages were used in the experimental work. The thermal conductivity is related to the air-dry density of wood-particles aggregate concrete. The relation is liedclosely within the predictions presented in ACI 213 committee report. The range of air dry density was about 1400 to 1900 kg/m3.

This work presents an experimental study on both short-term and long-term deflections for a period more than seven months of reinforced high and normal strength reinforced concrete two-way flat plate panels. Four reinforced concrete panels with dimensions of (960×960×50) mm were investigated with simply supported edges. Concrete cube strength is about 75 MPa for HSC panels, and 30 MPa for the control panel. Sustain load kept along the entire test period and at the end, the loads is removed and the recoverable deflection was measured. It's been concluded that the rate of increase in HSC panels' long time deflection is less than that of NSC panels, also the longterm deflection is highly reduced by increasing the compressive strength of concrete and the long term deflection reduced about 20% when compressive strength increased from 25 to 65 MPa.