A. Jalali Gilani - Department of Civil Engineering, University of Guilan, Rasht, Iran
S. K. Gharachorloo - Department of Civil Engineering, University of Guilan, Rasht, Iran
M. A. Mehrdad - Department of Civil Engineering, University of Guilan, Rasht, Iran
M. A. Lashteh Neshaei - Department of Civil Engineering, University of Guilan, Rasht, Iran

In reality, sea waves are random and so does sediment transport. Today statistical and probabilistic view for this concept has grown rapidly among researchers andcoastal engineers. Specifically in vicinity of shore protection structures, such as seawalls; that induce reflection which leads to creation of standing waves and these phenomena drastically change surf zone flow regime and also the mentioned surf zone sediment transport. In this study a mathematical model is introduced that can transform wave height probability density function to horizontal velocity probability density function near seabed, in surf zone and in vicinity of seawalls. Afterwards this model is verified by experimental data obtained from coastal laboratory of Imperial College University.