B.Tech Civil Concreting Equipment — practice questions
25 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice B.Tech Civil Concreting Equipment in the app →Mixing time is specified per drum capacity. The unit prescribes a minimum mixing time of 1 minute for mixers uTilting drum-type concrete mixers can satisfactorily handle aggregates up to what maximum nominal size?Non-tilting drum mixers are limited to aggregates up to about 75 mm size primarily because:Pan-type concrete mixers consist of an open pan and a rotating star of blades, with the star and pan moving inIn a cableway, the two end towers are called the head tower and the tail tower. The drive that pulls the carriCableways are classified by tower combination into four families. Which set names all four families correctly?In a radial-travelling cableway, two backstays are required at the stationary tower whenever the angle of travFor cycle-time calculations the unit lists suggested cableway speeds. The carriage travel speed is taken as apConcrete batchers proportion ingredients by weighing each material separately for every batch. The unit notes Cylindrical concrete buckets are open at the top and discharge through a centre gate in the bottom. LightweighLaydown buckets, used where the charging height is low, differ from cylindrical buckets in that they:Bottom-dump buckets are used to place concrete underwater. The discharge gate of a bottom-dump bucket is:Energy imparted to a batch during mixing converts to heat in the concrete. The unit estimates this mixing-enerTo control concrete placement temperature, the mixing water can be chilled. The unit notes that one kilogram oOne kilogram of ice absorbs about 334 kJ when it changes phase to water at 0 °C. This makes ice attractive forLiquid nitrogen is used as an alternate cooling agent. The unit gives its boiling temperature as approximatelyCoarse aggregate is cooled by inundation in a tank of chilled water. With water at 2 °C, even 15 cm top-size aVacuum cooling of aggregates uses the lower boiling point of water at sub-atmospheric pressure plus the heat aCement is normally batched dry. To avoid moisture condensation that would adversely affect strength, the unit Embedded post-cooling pipes carry circulating cool water through hardened concrete. The unit specifies pipe ouThe unit specifies that individual embedded pipe runs may range from 180 to 360 m, with a target design lengthIn the post-cooling pumping plant, each pipe coil is supplied at a flow rate of approximately:In the heat-balance equation Eq. 7.2 for ice quantity, the latent heat of fusion of ice is assumed as which vaIn the heat-balance equation, the specific heat of cement is generally taken between:Refrigeration plant capacity for pre-cooling of mass concrete is expressed in tons of refrigeration. One ton o