d. Cost and Time Estimates . Cost and time estimates for the conduct 

 of stability models of coastal engineering structures vary with many fac- 

 tors, and providing information to derive even approximate estimates for 

 specific problems is difficult. However, examples of actual costs and 

 times previously expended to perform model studies, with estimates of 

 times and costs for conducting the same studies in 1976, may be helpful. 

 The following work items are involved in the conduct of stability models 

 for those structures discussed in this section, and may serve as a guide 

 in the preparation of estimates for such studies: 



(1) Preliminary model design and cost estimate, and neces- 

 sary travel, conferences, and correspondence before authoriza- 

 tion to conduct the model study. 



(2) Final model design. 



(3) Model construction. 



(4) Calibration of wave generator and wave measuring appara- 

 tus for the selected test conditions. 



(5) Conduct of model tests, including necessary modifications 

 of model, computer time, required drafting and photography, prep- 

 aration of monthly progress reports and model demonstrations, 

 and conferences with representatives of the sponsoring agency. 



(6) Analysis of test results after testing has been completed; 

 the preparation for and the hosting of a final conference to pre- 

 sent and discuss the test results. 



(7) Preparation of first draft of the final report, which is 

 usually sent to the sponsoring agency for review and comment. 



(8) Preparation, publication, and distribution of the final 

 report . 



(9) Any authorized funds remaining in the job account after 

 completion of the study are returned to the sponsoring agency. 



The total costs for conducting the model studies, and the approximate 

 times and costs for the different items listed above, are given in Table 

 6-7 for five of the example model studies. 



The study concerning the stability of a vertical -wall parapet on 

 rubble-mound breakwater at Indiana Harbor, Indiana, was conducted in 

 1952; no cost records are available. However, it is estimated that about 

 $34,000 would be required to conduct the same study in 1976. The detailed 

 costs given for the five example model studies are the costs accrued at 

 the time each study was conducted; i.e., during the period 1963 to 1971. 

 The estimated costs of these studies in 1976 are presented in Table 6-8; 

 the actual time and costs from Table 6-7 are shown for comparison. 



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