Test: Engineering Equipments - 2 - Civil Engineering (CE) MCQ

Area = 15000 m²
Bulldozer moves 2500 m in 1 hr.
∴ Area cleaned in 1 hr

Grade resistance is measured in percent slope. Uphill grades are normally referred to as adverse grade expressed as positive percentage while downhill grades are referred to as favourable grades expressed as negative percentage.
Grade resistance does not depends on the type of equipment or the condition or type of road.

Productive capacity of a hauling unit

Where payload is the maximum recommended load for a hauling unit as prescribed by the manufacturer. Cycle time = Loading time + hauling time + dumping and turning time + return time + spotting and waiting time.

The output of a power shovel depends on,
(i) class of material
(ii) depth of cut
(iii) angle of swing
(iv) job conditions
(v) management conditions
(vi) size of hauling units like trucks
(vii) skill of operator
(viii) physical condition of the shovel
The optimum depth of cut is that depth at which the output is greatest and dipper comes up with full load without excessive downward pressure and tension. This depth varies with the type of soil and size of the dipper.
Ideal production of a shovel is based on operating at 90° angle of swing.

Operating factor = Engine factor x Time factor Engine factor accounts for operating at rated H.P. during maximum output and below rate H.P. for balance of cycle time.
Time factor accounts for shut down time proportion.

When loaded the grade resistance will be 5.5% and when empty the grade resistance will be 1.5%.
Total resistance = roiling resistance + grade resistance.
When travelling loaded the weight

When travelling empty the weight = 27t
Thus rimpull

Total discharge delivered = 90 + 60 = 150 LPS at delivery head of 18m.
The pumps work in parallel,

Power Shovel is used in excavation of earth in confined area or pit.
Hoe is used in excavation of trenches because trenches need precise control of dimensions and Hoe is suitable for this purpose.
Clamshell is used in rehauling of loose or excavated material.
Bulldozer is used in clearing and scrubbing of worksite.