本文旨在探討以不同水深、波高、週期的規則波浪通過不同孔隙底床的波高衰減情形。除了測得的孔隙率外，以無因次化關係建立無因次化參數群:波高衰減因子( 、波浪尖銳度、波高水深比、 Ur、無因次化波長距離 ，且利用波高衰減因子建立不同孔隙底床下，波高衰減與波浪條件的迴歸方程式。

試驗結果顯示孔隙率大的底床、無因次化波長距離越長及波浪尖銳度大的情況下，會有較大的波浪衰減率。且通常較大的入射波高會產生較小的波高衰減因子，且得到孔隙率大的底床隨水深條件越淺時其消散長波的能力越佳之結論。也得到：當波浪通過5～7個無因次化波長後，其波高衰減因子的下降幅度也隨之和緩。

This study explored the damping phenomena of wave.

While the wave pass through the different porous bed,causing to decrease the wave height.In this study,the experiment conditions were used to simulate the situation,including the different water depth,incident wave height and period,and get the porous rate and wave height.

Utilizing these results to obtain dimensionless factors to show the relationship of the wave height and wave length,wave height,wave depth,et al..From the solutions,the effect of the wave damping was obvious under conditions of which are long wave,big porous bed and wave stepness.Besides,the more bigger wave height was, the more smaller the wave decay factor.

The decay appearance of the wave height was not conspicuous after the wave processed the distance after 5~7 wavelength.

In addition ,to demonstrate the more lower the water depth was,the more better the dispersion of long wave was.

1.Biot,M.A.(1941),”General Theory of Three-Dimensional Consolidation, ” Journal of Applied Physics,Vol.12,pp.155-164

2.Biot, M. A. (1956a)” Theory of propagation of elastic waves in a fluid-saturated porous solid. I. Low-frequency range,” J. Acoust. Soc. Am. 28, pp. 168-178.

3.Biot, M. A. (1956b)” Theory of propagation of elastic waves in a fluid-saturated porous solid. II. High-frequency range, ” J. Acoust. Soc. Am. 28, pp. 179-181.

4.Biot, M. A. (1962)” Mechanics of Deformation and Acoustic Propagation in Porous Media, ”Journal of Applied Physics,Vol,No.4,pp.1482-1498.

5.Chen,T.W.,Huang,L.H.and Song, C.H.(1997), ”Dynamic Response on Poroelastic Bed to Nonlinear Water Waves, ”Journal of Engineering
Mechanics,Vol.123,No.10,pp.1041-1049.

6.Cruz,E.C.,M.Isobe and A. Watenabe(1997), ”Boussinesq equations for wave transformation on porous beds, ”Coastal Eng.,Vol.30,pp.125-156.

7.Darcy,H.(1856),Les Fontaines Publiques de la Ville de Dijon,Dalmont ,Paris.

8.Das,B.M.(1983),Advanced..Soil..Mechanics,Hemispher.Pub.Corp.,McGraw-Hill,New York.

9.Gu,Z.and Wang,H.(1991), ”Gravity Waves Over Porous Bottoms, ”Coastal Engineering,Vol.15,pp.497-524.

10.Hunt, J. N.（1959）” On the damping of gravity waves over a permeable surface,” J. of Geophysical Res., Vol. 64, o. 4, pp. 437-442

11.Huang, L. H. and C. H. Song（1993）” Dynamic response of pro-elastic bed to water waves,” J. of Hyd. Eng., ASCE, Vol. 119, No. 9, pp. 1003-1020.

12.Hsu,J.R.C., Jeng D.S.and Tsai,C.P.(1993), ”Short-Crested Wave-Induced Soil Response in a Porous Seabed of Infinite Thickness, ”International Journal for Numerical and Analytical Methods in Geomechanics Vol.17,pp.553-576.

13.Hsu,J.R.C.and Jeng D.S.(1994), ”Wave-Induced Soil Responses in
an Unsaturated Anisotropic Seabed of Infinite Thickness, ” International Journal for Numerical and Analytical Methods in Geomechanics Vol.18,pp.785-807.

14.Hsu,J.R.C.,Lin,Y.S.and Jeng D.S.(1995), ”Effect of Variable Permeability and Shear Modulus on the Wave-Induced Soil Response in a Porous Seabed, ”Proc. Conf. On Oceaan Engineering in R.O.C.,Tainan,Taiwan,pp.831-848.

15.Huang, C. H., E. C. Zhang and J. F. Lee（1995）” Nonlinear viscous wave-fields generated by a piston-type wavemaker,” Proc. Fifth Int. Offshore and Polar Eng., Con. Vol. III, pp. 34-41.

16.Jeng. D. S. (1997) ”Wave-induced seabed response in front of a breakwater. ” Ph. D. Thesis, The University of Western Australia, Australia

17.Jeng. D. S. (2001) "Wave dispersion in a porous seabed." Ocean Eng. 28 (12), 1585-1599

18.Liu, L. F. （1973）”Damping of water waves over porous bed,” J. of. Hyd. Div., ASCE, 99, No. HY12, pp. 2263-2271.

19.Madsen,O.S.(1974), ”Wave-Induced Pore Pressures and Effective Structures, ”J.Waterways,Harbours and Coastal Engineering Division,ASCE,Vol.100(WW3),pp.169-188.

20.Madsen,O.S.(1978), ”Wave-Induced Pore Pressures and Effective Stresses in a Porous Bed”, G.e., Vol.28,NO.4,pp.377-393.

21.Putnam, J, A.（1949）” Loss of wave energy due to percolation in a permeable sea-bottom,” Trans. Am. Geo. Un. 30, pp. 349-356.

22.Reid, R. O., and K. Kajiura（1957） “On the Damping of Gravity Waves over a Permeable Seabed” Trans. Am. Geophys. Union, Vol.38

23.Sollitt,C.K. and Cross,R.H. (1972), ”Wave Transmission Through Permeable Breakwater, ”Proc.13th Coastal Engineering Conf., ASCE,Vancouver,pp.1827-1846.

24.Tsui, Y. ,and Helfrich, S. C.(1983) ” Wave-induced Pore Pressure in Submerged Sand Layer. ” J. of Geotech. Eng. , ASCE , 109, NO.4, pp.603-618.

25.Yamamoto,T.,Koning,H.L.,Sellmeiher,H. and Van Hijum,E.V.(1978),
”On the Response of a Poro-elastic Bed to Water Waves, ”Journal of Fluid Mechanics,Vol.87,pp.193-206.

26.宋長虹（1993）”水波作用下多孔彈性體底床動力反應之研究”，國立台灣大學土木工程學系研究所博士論文。

27.李柏宏（1994）”波浪作用下可透水底床之孔隙水壓及流場之變化”，國立成功大學水利與海洋工程學系碩士論文。

28.林朝福,洪溫德（1994）”孔隙底床上之波譜變形” ， 第十六屆海洋工程研討會論文集，B239-255。

29.張興漢（1997）”剛性多孔介質底床對波高衰減的影響”，國立成功大學水利與海洋工程學系碩士論文。

30.藍元志 (2000) ”波浪與可透水彈性體互相作用之分析 ” ，國立成功大學水利與海洋工程學系博士論文。

31.林宇銜（2004）”孔隙斜坡底床反射波之實驗研究”， 國立成功大學水利與海洋工程學系碩士論文。

32.張學仁(2006)”孔隙斜坡底床上波浪衰減之試驗研究”，國立成功大學水利與海洋工程學系碩士論文。