土木工程(管理)毕业设计外文翻译.doc

Chapter 8 Equipment that is required throughout the project is included under equipment expenses, because it cannot be charged to any pasticular item of work.This equipment often includes the hoist towers and material-handling equipment such as lift trucks．As the estimator does a takeoff of each item。all equipment required should be listed so that the cost can be totaled in the appropriate column． Equipment required for one project only or equipment that might be used infrequently is often purchased for the one pfoiect and sold when it is no longer needed．In addtion to the operating costs．the difference between the purchase price and the selling price would then be charged to the project． 8-2 OPERATING COSTS The costs of operating the construction equipment should be calculated oh the basis of the working hour since the ownership or rental cost is also a cost per hour．Included are items such as fuel，grease，oil，electricity,miscellaneous supplies，and repairs．Operator wages and mobilization costs are not included in equipment-operation costs． Costs for power equipment are usually based on the horsepower of the equipment．Generally,a gasoline engine will use between O．06 to 0．07 gallon of gasoline per horsepower per hour when operating at full capacity．However,the equipment will probably operate at 55to 80 percent of full capacity pe rworking hour and will not operate for the full hour,but only for a portion of it． Example 8—1 Fuel Cost What is the estimated fuel cost of a 120-horsepower payloader?A job—condition analysis indicates that the unit wiU operate about 45 minutes per hour(75 percent)at about 70 percent of its rated horsepower． Assumptions： Fuel cost--$1．10 per gallon Consumption rate--O．06 gaUon per hp per hour Power utllization--70 percent Use factor一75 percent Fuel Cost Per Machine Work Hour=hp Rating×Power Utilization×Use Factor×Consumption Rate×Fuel Cost $4．16=120 hp×O．70×0．75×0．06Gallon