Estimating civil work

For feasibility studies on chemical plants, the Chemical Engineering Plant Index is recommended. However, if extensive civil work is being estimated, the ENR Index will be applicable. 

The estimated total cost to treat 125,000 m of soil from the Sviluppo Linate in Milan, Italy, at a rate of 25 tons per hour was 22 million. This estimate excludes excavation, debris removal, treatment and disposal of residual solids and effluents, site restoration, utilities, and the cost of bench- and pilot-scale testing (D158898, p. 333, 342). The vendor estimated that it would cost 150 to 200 per ton to treat 500,000 tons of soil using the B.E.8.T. Model 615 unit at a rate of 200 to 300 tpd. This estimate includes mobilization and demobilization costs but excludes the costs of site excavation, civil work, taxes, prescreening needs, site management, and effluent disposal (D199319, p. 6). 

The following unit costs provide ballpark estimates for civil work frequently encountered in chemical plant projects. Some have been obtained from contractors, others from published cost data, and the rest reflect the author s actual past experience. 

As mentioned in Section H.l the activity breakdown for this example is based on the preliminary estimate in Appendix L that was prepared without the benefit of P ID s and arrangement drawings. This breakdown would be barely adequate for tracking the civil work - site, concrete, and steel erection. However, it is not detailed enough for use for tracking electromechanical work - equipment erection, piping, electrical, and instrumentation. 

Using Eq. (52) and an effective delay of about 41 seconds (as in Section V.D) to estimate the likely PI performance, indicates a total residence time of about 25 minutes for a two-CSTR system with combined feedforward and feedback and a total residence time of 75 minutes without feedforward. As the cost of the feedforward controller is small compared to the cost of an extra tank or the extra civil work to accommodate a residence time above 30 minutes, the scheme with feedforward control and two CSTRs seems likely to be the preferred option to achieve good control. 

It is emphasised that the total price quoted, which includes only estimates for the civil work, represents a gennine ceiling price which wonld not be exceeded if the CEGB decided to proceed with negotiation for a contract for the whole station. 

A cost estimate has been prepared for the Ninotsminda UGS facility (see figure 6-3) - based on in-house RAMB0LL data. An adjustment has been introduced to take into account an estimated price difference for work carried out in Europe and Georgia. Particularly, construction and civil engineering works are presumed relatively cheaper in Georgia (a factor of 0.5 to 0.6 has been applied in this case)10. The price level is year 2003. 

The unique cellular morphologies of foams play a key role in determining their deformation mechanisms [51. They also allow the development of very simple alternative equations based on the mechanical models of beam theory (a branch of civil engineering) combined with scaling concepts, to estimate both the thermoelastic properties and the strengths of foams. Such simple relationships have been developed for foams manifesting elastomeric, elastic-plastic and elastic-brittle responses to mechanical defonnation. While much of this work has focused on the responses of foams to compressive defonnation because of the special importance of this deformation mode in many applications of foams, the responses of foams to tensile and shear deformation have also been considered within this theoretical framework. 

Geddes, S. 1996. Estimating for Building and Civil Engineering Works, 9th ed. Oxford, U.K. Bntterworths. A long-established textbook on estimating. 

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