CSM exam 2 study guide Complete And Verified Answers Solutions Graded A+.

Coarse Aggregates - correct answer retain through 4.75 mm sieve Aggregates are classified into two categories: Coarse Aggregates and Fine Aggregates. - correct answer True Fine Aggregates - correct answer passes through a 4.75mm sieve A bag of cement (1 cubic foot) typically weighs how many pounds? - correct answer 94 Hydraulic Cement - correct answer a chemical reaction between the dry ingredients and water Non-hydraulic cement - correct answer reacts with carbon dioxide in the air and then dries Type I Type II Type III Type IV Type V - correct answer General purpose Moderate Sulfate Resistant High early strength Low heat of Hydration High Sulfate resistance SCM - correct answer Supplementary Cementitious Materials SCM and Admixtures - correct answer fly ash slag silica fume physical soundness - correct answer freeze thaw wet dry pop out chemical soundness - correct answer Alkali- Silica reaction (ASR) Basic Composition of Concrete - correct answer Air = 6% Portland Cement = 11% Water = 16% Fine Aggregates = 26% Course Aggregates 41% Low Strength Concrete Medium Strength Concrete High Strength Concrete Very High Strength Concrete - correct answer Less than 3000 psi 3000 to 6000 psi 6000 to 12000 psi more than 12000 psi Light Weight Concrete Structural Light Weight Concrete Normal Weight Concrete Heavy Weight Concrete - correct answer less than 90 pcf 90 to 120 pcf 140 to 150 pcf more than 200 pcf Translucent Cement/Concrete - correct answer Concrete contains optical fibers that can transmit the light from one place to another. Light Generating Concrete - correct answer Concrete contains gel consistency, which allows the light to pass inside and radiate. Graphic Concrete - correct answer Precast Concrete Structures which already has a design texture, environment friendly. Self-Healing Concrete - correct answer Concrete contains a bacteria which gets activated as cracks are generated and it excretes calcium carbonate which seals the cracks. 3-D Printing - correct answer Using technology which can create low cost / affordable housing within 24 hours. Why studying the air void system in concrete is important? - correct answer It is related with durability and flow of the concrete. Entrapped air - correct answer develops naturally during mixing, (large, irregular shape void) Entrained air - correct answer develops from the addition of an air-entraining admixture (small, spherical shape void) The Air-entraining Admixtures (AEA) is a chemical in liquid form that acts like _______________ which results in the formation of stable spherical bubbles during mixing. - correct answer foaming agent It is impossible to measure the amount of air content in concrete. - correct answer False Generally, ____________ water is used for concreting - correct answer Potable If water is polluted ( with chemicals), there will be no effect on concrete. - correct answer False Adding more water than needed in concrete will result in less strength. - correct answer True ______ water/cement ratio contributes to higher strength, _____ water/cement ratio dilutes the paste and contributes to _____ strength. - correct answer Low, high, lower It is the _______, and typically not the _______ of water which is most important in producing good quality concrete. - correct answer quantity, quality Usually, getting good quality water for concreting is not an issue in the United States because ______________. - correct answer Construction projects have sufficient budget Chloride - correct answer Can cause corrosion of steel reinforcement Sulfate - correct answer Can reduce long-term strength levels (durability issues) Organic matter - correct answer Effects on concrete are variable (best not to use) Sugar - correct answer Can retard the setting time Wastewater - correct answer Best to treat first, test, and the