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CONSTRUCTION TECHNOLOGY & maintenance. CEM 417. SOURCES FROM slide: MOHD AMIZAN MOHAMD MOHD FADZIL ARSHAD SITI RASHIDAH MOHD NASIR FKA, UiTM Shah Alam. WEEK 7. Construction Plants. WEEK 7. LEARNING OUTCOME. At the end of week 7 lectures, student will be able to :
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CONSTRUCTION TECHNOLOGY & maintenance CEM 417 SOURCES FROM slide: MOHD AMIZAN MOHAMD MOHD FADZIL ARSHAD SITI RASHIDAH MOHD NASIR FKA, UiTM Shah Alam.
WEEK 7 Construction Plants
WEEK 7 LEARNING OUTCOME • At the end of week 7 lectures, student will be able to : • Identify the types, functions, capabilities and selections of stationary machines. (CO2; CO3). • Identify the types, functions, capabilities and selections of compaction machines. (CO2; CO3).
STATIONARY POSITION MACHINES - GRAB • A crane fitted with a grabbing bucket • Excavating efficiency is dependent upon the self weight of the attachment • Limited for fairy loose soil • Fitted with interlocking teeth • The clamshell has no teeth and only use for stockpiling very loose material such as sand • The whole unit is hung from the crane jib on a hoist rope
STATIONARY POSITION MACHINES - FACE SHOVEL • Best operates from a flat prepared surface • Use for loading, excavation of embankment or berm, loosen and load material, mostly used in quarrying and road cuttings • Can be a crawler or wheeled mounted • Type of shovel:- • Face shovel • Drag shovel • Crowd shovel • Luffing shovel • Skimmer
crowding Dipper stick hoisting
STATIONARY POSITION MACHINES - FACE SHOVEL • Factors for selecting the most advantages size and type of shovel:- • Type of material to be worked • Depth of banks to be cut • Swing angle that must be turned • Confinement or space restrictions • Job mobility • Haul cycle of the transporting equipment • Amount of work available • Skill of the operator
STATIONARY POSITION MACHINES - BACKHOE • Also known as pull shovel, drag shovel or simply as hoe • Used for excavating below the level of the tracks, e.g. trenches, basement, foundations and for other excavation work in confine situation.
STATIONARY POSITION MACHINES - BACKHOE • Production rates depends on the depth of the excavation • The average bucket play load is equal to the heaped bucket capacity play load multiplied by the bucket fill factor • Bucket fill factor will depend on the type of soil • Fill factor e.g. :- • moist loan or sandy clay = 100% • Sand and gravel = 90 to 100% • Well blasted rock = 60 to 75%
STATIONARY POSITION MACHINES - DRAGLINE • May only be used as a rope operated machine, a comparable hydraulic system is not available • Suitable in excavating loose and soft soil below the level of the machine • May be used as an alternative to backhoe • The bucket is cast out long from a boom, so that wide apart of excavation and dumping is possible • E.g. for river bottom, channels, canals, ditches and trench • Not suitable for confined space
TRENCHERS • Designed to excavate trenches of constant width with considerable accuracy and speed • widths available range from 250 to 450mm with depths up to 4m • Work on a conveyor principle having a series of a small cutting buckets attached to two end less chains which are supported by a boom that is lowered into the ground at the required depth
Steel cylinder roller • Two types:- • Non vibrating • Vibrating rollers
Steel cylinder roller • Non vibrating • Two types:- • Tandem (two-axle) • Three wheeled • Both types are self-propelled • Able to be ballasted (added weight) by adding water or sand to the rolls • Ballast normally required when operating the roller but may be removed when it is to be transported • Maximum effective layer compacted is 250mm
VIBRATING ROLLER • Two major types:- • Vibrating smooth drum rollers • Tractor drawn • Self-propelled • Important factors when considering vibrating rollers:- • Dynamic force- force exerted by the roller. Centrifugal force generated by a revolving eccentric shaft and total dead weight of the roller frame and drum • Frequency of vibration – no. of revolutions per minute made by the eccentric shaft • Amplitude of vibration- eccentric shaft rotates, the drum assembly moves up and down. Amplitude is the total distance the drum travels vertically.
Pneumatic tired rollers • Used on pavements such as sprayed or asphalt mix bitumen surfacing work • Suitable when material is cohesive, such as clays, clayey gravels or loams which is free from rock
Self-propelled tamping foot roller Tower sheepsfoot roller Tamping roller • Has a steel drum fitted with ‘feet’ of one type of another • Example, sheepsfoot, wedgefoot and pad foot • Compacting layer up to 250 mm • Normal compaction for clay, clayey gravel and sandy clays • Poor performance on sandy gravels • Not suitable for compact sand