Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Hand auger can be used for depths up to ________
7 m
6 m
2 m
10 m
6 m
Hand augers are manual soil exploration tools used for shallow sub-surface investigations. Due to the physical limitation of manual labor and the mechanical strain on the auger assembly, they are effectively limited to a maximum depth of 6 meters in common soil types.
Hand augers are manual soil exploration tools used for shallow sub-surface investigations. Due to the physical limitation of manual labor and the mechanical strain on the auger assembly, they are effectively limited to a maximum depth of 6 meters in common soil types.
DmaxтАЛтЙИ6┬аm тАФ Practical depth limit for manual auger operation
The tool works by rotating a helical blade or post-hole cutter into the soil, which cuts and lifts the sample to the surface. As the depth increases, the weight of the rod string and the friction between the soil and the auger body make manual rotation physically exhausting and mechanically inefficient, establishing the practical threshold of 6 meters.
Hand augers are best suited for soft to stiff cohesive soils.
They are not effective in non-cohesive dry sands (borehole collapses) or very hard strata.
Borehole diameter typically ranges from 100 mm to 200 mm.
Used primarily for obtaining disturbed samples for identification and index property tests.
Low cost and portable.
No external power source required.
Ideal for shallow geotechnical investigations and environmental sampling.
Labor intensive at higher depths.
Cannot penetrate boulders or dense rock layers.
Sample is considered 'disturbed', limiting advanced shear strength testing.
Soil profile identification for shallow foundations.
Agricultural soil testing.
Locating ground water table in shallow depths.
Beyond 6 m, the friction and weight of the rod assembly necessitate the use of power-driven augers or mechanical boring rigs.
If the auger hits an obstruction before 6m, the exploration method must be switched to percussion or rotary drilling.
B is correct тАФ 6 m is the generally accepted maximum depth limit for manual hand auger operations in soil exploration.
Always remember that manual methods are limited by physical torque and weight; in exams, if the question specifies 'mechanical' or 'power auger', the depth limit significantly increases to 15-20 m or more.