本研究建立打樁物理模型試驗探討不同土壤阻抗下對打擊樁之波傳行為的影響，係利用向上滲流裝置給予試體不同超額孔隙水壓比之目標值，以改變土體有效應力進而達到產生不同樁周阻抗之目的，並於樁頭配置應變計及加速度計觀察樁頭受打擊時的受力與質點速度變化，根據李根榮(2023)所建立 之樁周評估指標(Gap Force)，為表明其物理意義本文改稱為總樁身阻抗力(Lumped Shaft Resistance Force, LSRF)，定義為打擊應力波來回一次的時間點下，樁頭應變與加速度所計算的力量差值，其大小反應打擊樁時的總體樁身阻抗和樁承載力。本研究結果顯示在飽和狀態下總樁身阻抗力LSRF隨模型樁埋置深度增加而上升，並透過滲流控制系統在相同埋置深度下進行打擊與樁載重試驗結果顯示，隨著超額孔隙水壓比上升，樁周阻抗下降，所計算的LSRF亦隨之下降，且單次打擊的貫入量增加，而在相同滲流狀態下所求得樁之極限承載力與LSRF呈線性關係。模型試驗成果驗證數值模擬之可靠性及LSRF之潛在應用性。

This study established a physical modeling for pile driving to investigate the impact of different soil resistances on wave propagation behavior in driven piles. An upward seepage device was used to apply different target values of excess pore water pressure ratios to the test specimens, changing the effective stress to create varying soil resistances. Strain gauges and an accelerometer were installed at the pile head to observe changes in force and particle velocity during pile driving. Li (2023) established the soil shaft resistance assessment index, referred to as the Gap force, and defined it as the differential force computed from the pile head strain and acceleration measurements corresponding to the moment when the stress wave propagates from the pile head to the pile base and returns(2L/c). This index reflects the overall pile shaft resistance and bearing capacity during driving. This study renames it to Lumped Shaft Resistance Force (LSRF) to better reflect its physical significance. The results show that LSRF increases with the embedment depth of the model pile under saturated conditions. Further tests using the upward seepage control system at the same embedment depth, revealed that as the excess pore water pressure ratio increased, soil resistance decreased, leading to a reduction in calculated LSRF and an increase in single strike penetration. Moreover, a linear relationship was found between the ultimate bearing capacity and LSRF under the same seepage conditions. The model test results validate the reliability of numerical simulations and the potential applicability of LSRF.

1. 陳圭璋、李豐博(1990)。「打擊樁承載力之研究」。港灣技術研究所，研究報告。
2. 張文忠、周仕勳、李根榮(2022)。「基於波傳理論之打樁風險預警模擬與模型試驗規劃」。財團法人工業技術研究院，期末報告。
3. 張文忠、李根榮、張雅慈(2023)。「離岸管樁即時滑樁風險預警技術研發與測試」。財團法人工業技術研究院，期末報告。
4. 李根榮(2023)。「基於波傳理論之滑樁預警架構發展」。國立成功大學土木工程學系，碩士論文。
5. 鄒政霖(2023)。「利用滲流控制不同孔隙水壓比下之側推樁土互制行為」。國立成功大學土木工程學系，碩士論文。
6. 黃俊鴻、楊志文(2000)。「基樁載重試驗承載力判釋方法之探討與建議」。地工技術，(80)，5-16。
7. Deeks, A. J., & Randolph, M. F. (1993). “Analytical modelling of hammer impact for pile driving.” International Journal for Numerical and Analytical Methods in Geomechanics, 17(5), 279-302.
8. Goble, G. G., & Rausche, F. (1970). “Pile load test by impact driving.” In Highway Research Board Annual Meeting, Washington, DC.
9. Goble, G. G., Raushe, F., and Likins, G. E. (1980). “The analysis of pile driving-a state-of-the-art.” In Proceedings of the International Seminar on the Application of Stress-wave Theory to Piles, Stockholm, 131-161.
10. Ishihara, K. (1998). “Basic soil mechanics.” Kajima Institute Publishing Co., Ltd.
11. Iwan, W. D., Moser, M. A., & Peng, C. Y. (1985). “Some observations on strong-motion earthquake measurement using a digital accelerograph.” Bulletin of the seismological society of America, 75(5), 1225-1246.
12. Lu, J., Guang, H., Cui, L., Liu, J., Wang, C., & Kumar, S. A. (2023). “Experimental study on penetration characteristics of an open-ended pile under static and dynamic driving methods.” Soil Dynamics and Earthquake Engineering, 166, 107770.
13. National Instruments. (2003). “PID control toolset version2003.” User manual.
14. Ogawa, N., Ishihara, Y., Ono, K., & Hamada, M. (2018). “A large-scale model experiment on the effect of sheet pile wall on reducing the damage of oil tank due to liquefaction.” In Proceedings of the International Conference on Press-in Engineering First International Conference. 193-202.
15. Paikowsky, S., & Chernauskaus, L. R. (2008). “Dynamic analysis of open ended pipe piles.” In Proceedings of 8th international conference on the application of the stress wave theory to piles, Lisbon, Portugal. 59-76.
16. Paik, K. H., & Lee, S. R. (1993). “Behavior of soil plugs in open‐ended model piles driven into sands.” Marine Georesources & Geotechnology, 11(4), 353-373.
17. Randolph, M. F. (1991). “Analysis of the dynamics of pile driving.” In Advanced geotechnical analyses. 233-282.
18. Rausche, F., Moses, F., & Goble, G. G. (1972). “Soil resistance predictions from pile dynamics.” Journal of the soil mechanics and foundations division, 98(9), 917-937.
19. Rausche, F., Goble, G. G. and Likins, G. E. (1985). “Dynamic determination of pile capacity.” Journal of Geotechnical Engineering, 111(3), 367-383.
20. Richart, F. E., Hall, J. R. and Woods, R. D. (1970). “Vibrations of soils and foundations.”
21. Smith, E. A. L. (1960). “Pile-driving analysis by the wave equation.” Journal of Soil Mechanics and Foundations Division, 86(4), 35-61.