CONSTRUCTION TECHNOLOGY &maintenance

CEM 417SOURCES FROM slide:

MOHD AMIZAN MOHAMDMOHD FADZIL ARSHADSITI RASHIDAH MOHD NASIRFKA, UiTM Shah Alam.

Construction Plants

WEEK 7

WEEK 7

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).

LEARNING OUTCOME

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

hoisting

Dipper stick

crowding

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 - FACE SHOVEL

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.

Typical Hydraulic Operated Backactor

DETACHABLE TEETH DEPEND ON THE TYPE OF SOIL

DETACHABLE TEETH DEPEND ON THE TYPE OF SOIL

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 - BACKHOE

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

STATIONARY POSITION MACHINES - DRAGLINE

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

TRENCHERS

COMPACTION EQUIPMENT

COMPACTION EQUIPMENT

STEEL CYLINDER ROLLER

Two types:- Non vibrating Vibrating rollers

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

STEEL CYLINDER 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.

VIBRATING ROLLER

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

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

Tower sheepsfoot rollerSelf-propelled tamping foot roller