Field testing of single instrumented steel driven batter piles under vertical vibrations

The forced vertical vibration tests were performed in the field on 3.3-m-long driven steel pipe on a single vertical pile, P1 (β = 0°), and single batter piles, P2 (β = 10°) and P3 (β = 20°), for four different eccentric moments (W.e = 0.225, 0.885, 1.454 and 1.944 N-m) under the static load (Ws) of 12 and 14 kN. The field test results include the determination of frequency–amplitude response, soil–pile separation length, dynamic axial load and bending moment of piles under vertical vibrations. It is found from the test results that the batter piles, P2 and P3, show an average increment of 9.6 and 43.6% in peak displacement, while batter piles, P2 and P3, show an average decrement of 3.4 and 15.1% as compared to the vertical pile, P1. It is found that the soil–pile separation length (ls) for vertical pile, P1, is less than batter piles, P2 and P3. The results also show that the batter piles possess lower distribution of dynamic axial load and higher dynamic bending moment in a pile along the depth as compared to the vertical pile.