Chapter 3: Equipment Productivity

1 2003 by CRC Press LLC 3 Equipment Productivity Introduction Heavy/Highway Construction Projects Equipment Productivity Bulldozer Productivity Excavator Productivity Scraper Production Municipal/Utility Construction Projects. The Mechanized Excavation System The Guidance Control Sy stem The Propulsion System The Spoil Removal System The Control System The Pipe Lubrication System Equipment Cost Preventive Maintenance Mobilization of Equipment Introduction Whether a construction contract is unit price, lump sum, or cost-plus; whether the construction projectis to be linear ( , concept design procurement co nstruction) or fast-track ( , design/build),the cost of construction is a major factor in all projects.

2 The major factors that impact construction costsare materials, labor, Equipment , overhead, and profit. The cost of Equipment for civil engineeringco nstruction projects can range from 25 to 40% of the total project illustrates the ability to influence the construction cost of a project. The greatest influenceto construction cost occurs at the front end of the project. Assumptions made by design engineers duringthe conceptual and design phases of a project dictate the choice of Equipment that will be used for theparticular project, just as it will dictate the choice of materials used in construction.

3 Thus, sometimesthe design may, in fact, restrict the best and most cost-effective solutions from being utilized. For example,many sewer projects are designed on the basis of traditional specifications, materials, and Equipment ,when more advanced materials, techniques, and Equipment may, in fact, be safer, more environmentallyand socially acceptable, and more cost-effective. This is especially true of sewer projects in urban areas,where modern construction techniques, such as microtunneling and pipebursting, utilizing new pipematerials such as glass fiber-reinforced polymers (GRP) and high-density polyethylene (HDPE), arereplacing the traditional dig and replace methods of sewer is important for design engineers and construction engineers to be knowledgeable about construc-tion Equipment .

4 Construction Equipment is an integral part of the construction process. The cost ofconstruction is a function of the design of the construction Chapter will provide an overview of construction Equipment selection and utilization will describe typical Equipment spreads associated with two major classifications of civil engineeringconstruction projects: heavy/highway and municipal/utility. Methods for determining Equipment pro-ductivity and cost will be discussed. Tom lseley Blackhawk-PAS, Inc., South Carolina Sanjiv Gokhale Vanderbilt University 3 -2 The Civil Engineering handbook , Second Edition Heavy/Highway Construction Projects These projects include new road construction, dams, airports, waterways, rehabilitation of existingro adways, marine construction, bridges, and so on.

5 Each project can be segmented into various phasesor operations. The Equipment spread selected for a specific construction operation is critical to the successof the (a) illustrates a typical sequence of activities for the construction of a new highway. Thishighway project contains culverts and a bridge. While there will be some overlap in Equipment utilization,each activity must be evaluated carefully to identify all operations in the activity and to ensure that theequipment selected for each operation is compatible with the tasks to be completed.

6 Figure (b) liststhe activities associated with the project, the duration of each, and whether the activities are critical ornoncritical. The intent is not to provide a detailed description of each activity but to illustrate howequipment selection and utilization are a function of the associated variables. For example, the firstactivity (clearing and grubbing) is critical, as no activity can begin until the project site is cleared. Eventhough clearing land is often considered to be a basic, straightforward activity, it is still more an art thana science.

7 The production rates of clearing land are difficult to forecast, because they depend on thefollowing factors: The quantity and type of vegetation Purpose of the project Soil conditions Topography Climatic conditions Local regulations Project specifications Selection of Equipment Skill of operatorsTo properly address these variables requires research and a thorough evaluation of the site to determinethe following: Density of vegetation Percent of hardwood present FIGURE Ability to influence construction cost over time. ( Source: Hendrickson, C. and Au, T.)

8 Project Manage-ment for Construction. Prentice Hall, Englewood Cliffs, NJ.)Level of Influence on CostConstruction Cost100%StartProject Time0%100%Ability toInfluence CostsConceptual Planningand Feasibility StudiesDesign andEngineeringProcurement and ConstructionStartupOperation andMaintenanceConstruction Cost 2003 by CRC Press LLC Equipment Productivity 3 -3 FIGURE (a) Typical sequence of activities for a new highway project; (b) activities associated with a new highway #1 Clearing &Grubbing22 Mar 93 15/0 Activity #3 FootingsDrivePilingColumnsGirdersApproac hSlabs21 Oct93 8/0 Activity #801 Dec93 12/0 Activity #1022 Jul93 14/58 Activity #1929 Jul93 14/0 Activity #612 Apr93 12/0 Activity #212 May9330/0 Activity #4 Unclassified ExcavationActivity #16 Activity #167 DescriptionA Typical Heavy/Highway ProjectEarly StartDur/Tot FltCriticalMilestoneActivity #15 Drainage Structures28 Apr93 10/0 Activity #5 Caps24 Jun9318 Aug9325/045/002 Nov9320/0 DressShouldersActivity #7 Class AA DecksActivity #9 PCCP or

9 ConcreteErosionControl17 Dec93 4/0 GuardRail Activity #1328 Dec93 6/012 Apr9306 Jul93 12/5820/9324 May9330/5812 Apr9330/5823 Dec93 3/002 Nov93 5/34 Activity #20 SuretrakRoadway with Concrete Pavementor PCCPRun Date : 20 Mar93 Start Date : 20 Mar93 Data Date : 22 Mar93 Finish Date : 11 Jan94 Activity #18 Subbase TreatmentActivity #12 Clean upand SellBarrierRails05 Jan94 5 Activity #14 PavementMarkingsActivity #1129512 19 263 10 17 24 317 14 21 285 12 19 2629 16 23 30 613 20 27 411 18 251613 20 273 108152229 AprilMayJuneJulyAugustSeptemberOctoberNo vemberDecemberJan.

10 '94 2003 by CRC Press LLC 3 -4 The Civil Engineering handbook , Second Edition Presence of heavy vines Average number of trees by size category Total number of treesA method for quantifying the density of vegetation and the average number of trees per size categoryis described in Caterpillar [1993] and Peurifoy and Schexnayder [2002, p. 179].The most common type of construction Equipment used for clearing and grubbing activities is abulldozer. The term bulldozer is used to define a tractor mounted with a dozing blade. Tractor size canvary from less than 70 flywheel horsepower (FWHP) to more than 775 FWHP.