CEMATEL LQ1 Short Quiz Compiled.docx.pdf

CEMENT € Dicalcium silicate 1. What is the usual liquid used in determining the specific gravity of € gypsum cement? € calcium silicate hydra...

CEMENT € Dicalcium silicate 1. What is the usual liquid used in determining the specific gravity of € gypsum cement? € calcium silicate hydrate € Gasoline € calcium hydroxide € Water 9. What are the characteristics of € Vinegar Pozzolan? € Kerosene € blended cement 2. Fineness of cement affects the € react with calcium hydroxide following: € natural cementitious material € Const of heating € siliceous/aluminous material € Rate of hydration 10. What are the compounds that € Amount of clinker produced contribute much to the hydration of cement? € Gypsum requirement € tricalcium silicate 3. List one of the four ingredients of cement. [Silicon, Calcium, Aluminum, € tetracalcium aluminoferrite Iron] 4. What do we call the ability of cement € tricalcium aluminate not to undergo large change in volume € dicalcium silicate during hydration? € Fineness AGGREGATES € Exothermic 1. Which are the basis of the maximum size of aggregates? € Soundness € dimension of concrete member € Shrinkage € spacing of rebars 5. What is the basis of the strength of cement? € sieve analysis € ASTM C348 € size of rebar € ASTM C109 2. If the percentage absorption of aggregate is 5%, what is its specific € Concrete cylindrical test gravity at oven dried condition if the specific gravity at SSD condition is 2.35? € ASTM C190 Round-off up to 2 decimal places. [2.24] 6. What is the standard specific gravity of 3. What are the inert and inexpensive cement? [3.15] material that occupies large percentage 7. The term hydration refers to the volume of concrete? [Aggregates] chemical reaction between cement, 4. What are the characteristics of concrete water, and aggregates. [FALSE] that aggregates affect? 8. What compound prevents flash setting? € workability  € strength € void content € cost € bond area € durability € durability 5. Among the choices, which are the 11. Which one is the desired grain size physical properties of aggregates? distribution or grading of aggregates to produce good concrete? € specific gravity € well graded € absorption € flat graded € grading € gap graded € soundness 6. Which one is the ideal texture of € Uniformly graded aggregates for concreting job? 12. Among the choices, which are the mechanical properties of aggreggates? € rough € bond € smooth € strength € honeycombed € toughness € glassy 7. What is considered the best shape of € durability coarse aggregates for concreting job? a. angular b. round WATER AND ADMIXTURE c. flaky 1. What is the best admixture to produce d. pointed self-compacting concrete? 8. What is the average diameter of the [Superplasticizer] aggregates if the fineness modulus is 2. Accelerator can be used with set 3.0? Answer in mm up to 1 decimal retarder in a concrete mix. [True] place. [0.6] 3. What should be the acceptable quality 9. If the rebar spacing is 1 inch (25.4 mm), of water for a concrete mix? what is the aggregate size (mm) that € Rainwater will produce the most economical concrete? € Water free from impurities € ¾” € Potable water € 1” € Purified water € ½” 4. The water inside the aggregates (or absorbed by the aggregates) shall be € 3/8” included in calculating the amount of 10. What are affected by the shape of water added to the concrete mix. [False] aggregates? 5. What is this pozzolan in the form finely divided residue which is a by-product of € water requirement coal combustion? [Fly ash]  6. What admixture do we use to advance € No effect at all the time that a structure can be made in service? [Accelerator] 2. What are the different methods of 7. Which admixture(s) can be used to determining the air content of fresh produce high strength concrete? concrete? € accelerator € pressure method € plasticizer € gravimetric method € air-entraining admixture € volumetric method € silica fume € penetration method 8. Among the choices, which are 3. What are the factors affecting admixtures? workability of fresh concrete? € pozzolan € aggregate grading € plasticizer € density of aggregates € accelerator € maximum size of aggregates € retarder € water content 9. What are the effects of plasticizer in a € air content concrete mix? 4. What is the method used to deposit € increase workability concrete under water? [Tremie] 5. Which one below is the acceptable € waterproof concrete diameter of pipe for pumping concrete if the maximum aggregate size is 19 € increase water content mm? € increase early strength € 60 mm 10. Which are the effects of set retarder in a concrete mix? € 30 mm € reduce early strength € 50 mm € improve workability € 40 mm 6. Choose from the list below which ones € lessen formation of cold joints are the purpose of curing. € hasten the hardening of € prevent water evaporation concrete € remove impurities from FRESH CONCRETE concrete 1. Is the strength of hard concrete affected € enhanced hydration of concrete by the workability of fresh concrete? € Yes, to some extent. € improve concrete surface 7. What are the different forms of € Yes, but consolidation can cure segregation in fresh concrete? it.  € separation of coarser € use of river gravel aggregates 14. What are the advantages of ready-mix concrete? € bleeding € no problem in workability € concrete slump € cheaper € separation of cement paste 8. What are the causes of shrinkage of € good quality control concrete? € can be used in congested site € heat of hydration 15. What is the term used for fresh concrete pumped under pressure? € loss of water in hydration € shotcrete € loss of water due to evaporation € batched concrete € over compaction of concrete € pumpcrete 9. What is the term used for fresh € forced concrete concrete pumped under pressure? 16. What are the acceptable curing method € shotcrete of concrete in the list shown below? € batched concrete € covering with cement € pumpcrete € spying with mortar € forced concrete € ponding with water 10. What is another term for shotcrete? € covering with wet sand or soil [gunite] 11. What is the term used for putting the 17. What is the type of shrinkage caused by concrete ingredients into a concrete water being used up in hydration? mixer? [charging] [Autogeneous] 12. Among those listed below, which are 18. What are the tests that can used to measurable properties of fresh measure the workability of fresh concrete? concrete? € bleeding € ball penetration test € segregation € flow table test € workability € slump test € air content € drop test 13. What are the possible causes of € flow test segregation of fresh concrete? 19. What is the term used in coating the € incorrect manner of transport inner sides of the mixer with an initial amount of mortar or cement paste? € gap grading [buttering] 20. What is the property of fresh concrete € improper vibration defining the time required to reach the  specified value of resistance to € 6”x12” cylinders penetration? [Setting Time] 21. What are the purpose of vibrating fresh € 6” cubes concrete? € 100mm x 200mm cylinders € proper filling of forms € 50mm cube € remove entrapped air 6. The concrete stress-strain curve is € introduce air-entrainment considered to be elastic up to what percentage of f’c? € provide additional workability 7. What contributes to the strength of concrete? HARD CONCRETE € strength of aggregates 1. The compressive strength of concrete used in structural design is obtained on € strength of bond how many days after mixing concrete? € strength of admixture € 30 days € strength of cement € 14 days 8. What is assumed density of normal € 28 days weight concrete in kg/cu.m.? 9. The shape of the standard specimen € 60 days used for determining the compressive 2. If the compressive strength (f’c) of strength and split-tensile strength of concrete is 21 MPa, what is the concrete? modulus of rupture of concrete (in MPa) € prism according to the Code? (2 decimal places) [2.84] € beam 3. Which one is the acceptable and realistic value of Poisson’s ratio of € cylinder concrete? € cube € 0.30 10. What is the term used for the long-term € 0.10 deformation of concrete due to application of sustained load? [creep] € 0.20 11. What are some of the mechanical properties of hard concrete? € 0.40 € compressive strength 4. If the compressive strength of normal weight concrete is 28 MPa, which one is € density the value of the modulus of elasticity, Ec? € modulus of elasticity a. 25.800 MPa € poison’s ratio b. 20,000 MPa c. 24,870 MPa d. 21,538 MPa 5. What are the acceptable sizes of specimen for compression test of concrete?