Geotechnical Design || All Questions Answered Correctly.

Name the 6 soil exploration methods correct answers -Geophysical Methods -Test pits -Hand Augers -Power Augers -Wash Boring -Rotary Rigs Name Geophysical Methods and their advantages and disadvantages correct answers Ground penetration radar, seismic surveys, etc. Advantage: inexpensive, tells groundwater, subsurface geology Disadvantage: no soil sample, mostly qualitative Test pit and its advantages and disadvantages correct answers Pit dug by hand or backhoe Advantage: cost-effective, detailed stratigraphy, disturbed samples easily obtainable Disadvantage: depth limited to 6m,difficult to excavate below groundwater Hand Auger and its advantages and disadvantages correct answers hand rotated auger Advantages: cost effective, portable, groundwater easily identifiable Disadvantages: Depth limited to 6m, labor-intensive, undisturbed samples can only be taken for soft clay Power Auger and its advantages and disadvantages correct answers Truck Mounted with continuous-flight augers Advantages: quick, use in uncased holes, undisturbed samples easily obtained, groundwater easily identified Disadvantages: Depth limited to 15m after that expensive, site must be accessible Wash Boring and its advantages and disadvantages correct answers Water is pumped to the bottom of borehole and soil washings are returned to the surface. Advantages: Can be used in difficult terrain, low equipment cost, used in uncased holes Disadvantages: depth limited to 30m, difficult to get groundwater level, must be accessible by motorized vehicle Rotary Drill and its advantages and disadvantages correct answers drill bit pushed by the weight of the drilling equipment Advantages: quick, drill through any soil, can drill to depth of 7500m, undisturbed samples easily recoverable Disadvantages: Expensive, accessible by motorized vehicle, difficult obtaining GWL Disturbed samples correct answers Hand Auger grabs, shovel, drilling grab, SPT samples Undisturbed Samples correct answers Thin-walled shelby tube, piston sampler, rotary core drilling, ground freezing