Madsen and White (1976) made a number of additional carefully controlled 
reflection measurements for smooth and rough steep-sloped structures under 
nonbreaking wave action. Based on these data, they developed an analytical- 
empirical model for predicting reflection coefficients for rough slopes with 
nonbreaking waves. 
Battjes (1974) used Moraes' data to develop an equation for predicting 
reflection coefficients for smooth slopes where the slope induces wave breaking. 
This technique is conservative for nonbreaking (surging) waves. Ahrens (1980) 
has made a number of irregular wave reflection coefficient measurements for 
overtopped and nonovertopped plane smooth slopes. 
A number of wave reflection measurements for laboratory breakwaters have 
been made. Seelig (1980) investigated rubble-mound and caisson breakwaters 
using monochromatic and irregular waves. Brunn, Gunbak, and Kjelstrup (1979) 
measured reflection coefficients for rubble-mound breakwaters and proposed an 
empirical prediction technique. Additional breakwater reflection data are 
available in Debok and Sollitt (1978) and Sollitt and Cross (1976). Madsen 
and White (1976) give a procedure for predicting reflection from rubble-mound 
breakwaters for nonbreaking waves. 
Chesnutt and Galvin (1974) and Chesnutt (1978) have made some of the most 
detailed measurements available of wave reflection from laboratory sand beaches. 
Little prototype data are available; however, Munk, et al. (1963) and Suhayda 
(1974) reported reflection measurements for beaches exposed to extremely low 
steepness swell waves. 
IIJ. EXPERIMENTAL TECHNIQUES 
The primary emphasis of this report is on the reanalysis of existing data 
from a number of published sources. However, some additional laboratory data 
were taken to supplement the sources; these data are reported in Appendix A. 
Goda and Suzuki's (1976) method was used to determine wave reflection coef- 
ficients. This method was selected because with the test setup used it gave 
consistent results which are as reliable as obtainable with other currently 
used procedures. Experience with this technique suggests that the error is on 
the order of 5 percent. A typical wave gage setup is illustrated in Figure 2, 
and a detailed discussion of the analysis method given in Appendix B. The test 
procedure uses three gages, located a minimum of 6 meters seaward of a test 
Incident Woves Reflected Woves 
SS <ag——_—_—__—_—_—_———_—_—__ 
|—_-_—- AL = 125 cm ———— 
O2:90cm 
pe a 
AL = 35cm 
Wave Gages Tank Bottom 
Figure 2. Wave gage array used to measure wave reflection. 
10 
