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26 Cards in this Set
- Front
- Back
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ASTM C617 These procedures for capping enable concrete cylinders and cores to meet the standard requirements for ———- and ———. |
Planeness Perpendicularity
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Equipment needed for the capping process includes capping ——-, ——- devices, and ——- pots. |
Plates Alignment Melting Plates |
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Plates for neat cement and high strength gypsum plaster caps should be made of ——-, ——-, ———, or ———. |
Glass Metal Granite Diabase |
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Sulfur Mortar cap plates should be formed against _______ or _______. |
Metal or Stone |
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The purpose of the guide bar or bull’s eye level is to ensure that caps remain perpendicular to the axis of the cylinder within 0.5 degrees. True or False? |
True |
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To avoid accidents during reheating of cooled sulfur, use melting pots that have ________ ________. |
Peripheral heating |
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The technician should use a stiff layer of ______ _______ ________ to cap fresh concrete cylinders. |
Neat Cement Paste |
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Hardened concrete cylinders should be capped with ____________________, ____________________, or ____________________. |
High Strength Gypsum Neat Cement Paste Sulfur Mortar |
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Plaster of Paris and mixtures of plaster of Paris and Portland cement are examples of suitable high strength plasters. True or false? |
False |
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Sulfur Mortars and high strength gypsum cement cubes must demonstrate a minimum compressive strength of __________ or __________ -__________ whichever is greater. |
5000 Psi Cylinder Strength |
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The cement paste should be applied to freshly molded cylinder from ______ to _______ hours after molding. This is to allow for _____________ of the concrete specimen. |
2 to 4 hours Setting |
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The strength of the paste depends on: A) the water- cement ratio B) time C) the equipment used D) type of cemebt |
A, B, D |
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A slight twisting action will help eliminate ______ ______ and air ______ when the capping plate is placed onto the mound of paste. |
Excess Paste Air Voids |
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Neat Cement Paste caps should not be used on dry specimens because the caps may _________ and ________ when dry. |
Shrink and crack |
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The technician should remove all ________ or _________ materials from the ends of hardened concrete cylinders before capping. |
Oily or waxy |
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_______ the pot and recharge with fresh material at intervals to ensure that the oldest material in the pot has not been used more than ______ times. |
Empty 5 times |
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When capping concrete cylinders with a compressive strength of 5000 psi (35 MPA) or greater, it is permitted to reuse compound recovered from the capping operation of old caps? True or false? |
False |
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To avoid _____________, the sulfur mortar should be dry when it is added to the pot. It should be kept away from __________ when heating. |
Foaming Water |
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The melting pot for the sulfur must have a _______ and _______-_______ for _____________. |
Hood Exhaust Fan Ventilation |
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Hydrogen sulfide gas, which may be produced during capping, may be _______ in high concentrations. In lower concentrations, the gas may result in __________, ________-_______, ___________, ___________, and ___________ of the _______. |
Lethal Nausea, stomach distress, dizziness, headache, and irritation of the eyes. |
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ASTM C617 describes procedures for creating plane surfaces on the ends of freshly molded cylinders, hardened cylinders, and drilled cores. True or False? |
True |
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Prepare sulfur mortar for use by heating to a temperature __________________.? A) of approx. 140 C (265 F) B) no less than 130 C (265F) C) between 130 to 145 C (265 to 290F) D) of approx. 145 C (290F) |
C) between 130 to 145 C (265 to 290F) |
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The plate used to cap a cylindrical concrete specimen can NOT be fabricated from which of the following materials: A) polished granite B) Machined metal C) Plexiglas D) Glass
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A) polished granite |
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The cement paste should be applied to the freshly molded cylinder from _______ to ________ hours after molding. This is to allow for setting of the concrete specimen. A) 1,2 B) 2,4 C) 4,6 D) 6,8 |
B) 2,4 |
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The melting pot for the sulfur mortar must be located under a hood with an exhaust fan for: A) cooling B) heating C) ventilation |
C) Ventilation |
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When checking the thickness of a cap, obtain at least _______ random pieces distributed over the entire area of the cap. A) 2 B) 4 C) 6 D) 8 |
6 |
