314 



PATTERSON-SIMMONS. MODEL STUDIES 



[Ch. 17 



Brigantine Bridge. The model was constructed of concrete with a 

 movable-bed section molded in sand that extended from Ventnor, New 

 Jersey, on the southwest to a point on Brigantine Beach approximately 

 22,000 feet northeast of the inlet, and offshore to about the 30-foot 

 contour of depth in the ocean. The model was constructed to linear 

 scale ratios of 1:500 horizontally and 1:100 vertically, and provisions 



Fig. 9. Location map, Absecon Inlet model study. 



were made for reproducing tides in the ocean and inlet, littoral currents 

 parallel to shore in either direction, and waves from any direction from 

 south to northeast. 



As explained previously, the verification of a movable-bed model is 

 of great importance, inasmuch as this process establishes the accuracy 

 with which the model reproduces the bed-movement characteristics of 

 the prototype and also establishes the time scale for bed movement. 

 For the Absecon Inlet study, the verification period was selected as 

 the period between prototype surveys of January, 1936, and January. 

 1939. The hydraulic forces in the model were then adjusted empiri- 

 cally until the movement of sand in the model was such that all 

 changes in bed configurations which occurred during the 3-year period 



