Cost and production estimation for a cutter suction dredge

Abstract

The need for accurate cost estimates is well recognized in the dredging industry. In order for a dredging contractor to efficiently execute a project from its conception to its completion, an accurate estimate of the final cost is imperative. The most practical method of determining the cost is through the use of a computer program, based on the capability of personal computers to manipulate large amounts of data and perform difficult calculations without error. Development of such a program requires both theoretical and practical knowledge of the dredging process. There are several existing cost estimation and production estimation programs in use in the dredging industry today. Several different algorithms to estimate production have been developed over the years, and there are some non-proprietary production programs. However, the majority of both cost and production estimation programs are proprietary and therefore not available to those apart from the individual company. Therefore, the need exists for a program of this type which can be made available to the general public. This report discusses the development of a new generalized cost and production estimation program. Both slurry transport theory and centrifugal pump theory are incorporated into the production component of the program. This is necessary to obtain an accurate production estimate in the absence of a great deal of data for a specific dredge. Practical knowledge of costs associated with the dredging process is applied in the cost estimation component. The gram is written in the Quattropro(version6.01)spread sheet formatand may be used in conjunction with Microsoft Windows version 3.1 or Windows95. The acronym CSDCEP has been given to the program, which stands for Cutter detailing the operation of the program is available. The cost estimate results produced by CSDCEP were compared with actual data and government cost estimates for twenty one completed projects. The average difference between the estimate and the actual costs was twenty four percent. CSDCEP is a generalized cost estimating program that yields a good approximation of the final dredging cost.