(XcM'b 



BERM 



<Xr M ) 



CM'B- 



Figure 5. Definition sketch for bar and berm features 



45. In the various cases, a bar formed if material was deposited in the 

 offshore region of the profile (main direction of sand transport offshore), 

 whereas a berm formed if material was deposited on the foreshore (main direc- 

 tion of sand transport onshore). A more thorough discussion of beach profile 

 morphology and its relation to the controlling wave and sediment parameters is 

 given by Larson and Kraus (1988a). They used data presented in this report 

 together with data from an independent experiment performed at the Central 

 Research Institute for Electric Power Industry (CRIEPI) involving another 

 large wave tank (Kajima et al. 1983). 



Classification of Bar and Berm Profiles 



46. The response of the beach profile to the waves incident upon it may 

 be classified according to whether material is mainly transported offshore to 

 create a bar or transported onshore to create a berm. In the process of bar 

 formation, the foreshore erodes and the shoreline typically retreats, whereas 

 in berm formation the foreshore accretes and the shoreline advances. 



47. Criteria have been previously proposed to classify beach profile 

 response as bar-type (erosional) or berm-type (accretionary) . Here, a new 

 classification scheme is presented which is based solely on data obtained 

 from profile change generated in the LWT and in the more recent CRIEPI experi- 

 ments performed in Japan (Kajima et al . 1983). The agreement in trends of the 

 data obtained with the LWT and the CRIEPI experiments performed with modern 



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