
Subsurface Investigation Building structure system
Soil Boring Machine • Flight Auger system • Wash Boring
Rotary Drilling • Undisturbed • Machine Require
Wash Boring • Rotary Drilling • Percussion Drilling
Thin wall (Shelby tube) Split Sampler Sampling
Field Testing Standard Penetration Test (SPT) ASTM D1586 –140 lb (63.5 kg)- Falling 30 inches (0.76 cm) Test in 3 interval @ 150 mm Use only the 2 last 2 interval =150x2 =300 mm = 1 ft The unit is Blow per foot
Interpretation • Classify soil to be clay or sand • C for clay • f for sand • Calcuate the strength parameter -Correction for SPT -Calculate the strength parameter
Strength parameter for sand (Peck’s Approach) • No effective stress calculation • Empirically correlation
Parry (1977) Adjustment with overburden pressure
Strength parameter for clay Procedure for classify soil • Start with water content and unit weight • Check strength parameter with index properties • Divide soil layer
Soil Boring • Number of Boring • Depth of boring Thailand Depth of Boring is 30 or 60 m.