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  2. CONSTRUCTION PROCESS The ‘construction process‘ (sometimes called the ‘construction stage’) is the physical processes of building, landscaping or refurbishing plus all the associated activities, such as demolition, site clearance, administration and so on.
  4. PLANNING AND DEVELOPMENT Before getting invested in a project, a construction manager needs to make sure it's feasible. In this stage, you'll do extensive preliminary research to decide if you want to proceed. Ask the following questions: • What’s the expected ROI? • What are the risk, and are they manageable? • Is this project a good fit for my company?
  5. DESIGN • Stakeholders at this phase, crate increasingly precise renderings of the final build. • It is critical to the success of a project, as all panties need to be in agreement about the design specs.
  6. PRECONSTRUCTION • In this stage, you'll develop a course of action to see the project through to completion. • Determine the project workflow
  7. PROCUREMENT • The goal in this stage is to get what you need as quickly and as economically as possible. You don't want to wait too long to order materials and hold up the next steps in a project.
  8. CONSTRUCTION SAFETY • When it comes to safety, the construction industry has a higher fatality rate than the national average. To reduce worker injuries and fatalities, OSHA has created a comprehensive set of safety standards, as well as a construction safety digest, safety training guides, and more.
  9. Safety should be first and foremost on every employer’s and employee’s mind. And given that 20.5% of worker fatalities in 2014 were in construction, it’s imperative that employers make sure the workplace is safe. To this end, OSHA requires that employers maintain a safe work environment and follow all related OSHA safety and health standards. Most of the applicable standards can be found in 29 CFR 1926, Safety and Health Regulations for Construction. Improving construction safety is a complex task that requires a holistic safety approach. This requires employers to use the following methods: * Engineering controls * Safe work practices * Personal Protective Equipment (PPE) assessment and training * Daily inspections and preventive maintenance * Employee injury and illness programs Using each of these methods will ensure that workers remain safe by eliminating and reducing workplace hazards.
  10. CONSTRUCTION PLANNING • * Construction planning includes defining all the relevant processes, procedures, and policies you need to put in place to meet the needs of a specific project. • * Construction planning helps assure that projects are completed on time and within budget, meet quality standards, and ensure safety protocols for your crew. • * Planning clarifies responsibilities between owners, builders, and tradespeople, leading to excellent communication and teamwork.
  12. ECONOMIC COST • It is critical for construction firms to accurately estimate the equipment cost as part of the total cost of the construction project. • An inaccurate estimate of the cost of construction equipment could negatively impact a company's profit margin.
  13. EQUIPMENT COST CAN BE CLASSIFIED TO: Ownership Cost Operating Cost  Purchase expense  Salvage value  Interest cost or cost of capital investment  Major repairs & overhauls  Property taxes  Insurance cost  Storage & miscellaneous  Repair and maintenance cost  Fuel cost  Cost of lubricating oil, filter and grease  Tire cost  Equipment operator wages  Cost of replacing high-wear items  Cost of mobilization, demobilization and assembly
  14. Ownership cost is the total cost of owning construction equipment, regardless of whether it is used or not in the project. 1. Purchase Expense - refers to the cash outflow experienced by the company in acquiring ownership of the machine. 2. Salvage value - represents the expected cash inflow from disposing of equipment at the end of its useful life. 3. Interest cost or cost of capital investment - is the annual cost of interest on borrowed money or the capital investment required to acquire ownership of the equipment. 4. Major repairs & overhauls - are the costs incurred to bring an asset back to an earlier condition or to keep the asset operating at its present condition. 5. Property taxes - are taxes to be paid to the state or central government. 6. Insurance cost - comprises the expense for covering a fire, a theft, and equipment damage. 7. Storage and miscellaneous - is the cost of maintaining storage yards and facilities.
  15. Operating cost is the sum of those expenses an owner experiences by working a machine on the project. It is incurred only when the equipment is operated. The operating cost of the equipment is influenced by various parameters number of operating hours; location of job site; operating conditions; category of equipment etc. 1. Repair and Maintenance - refers to normal maintenance-type repairs includes the cost of replacement parts and labor charges. 2. Fuel cost - Construction equipment is typically powered by internal combustion engines that run on either gasoline or diesel fuel. 3. Cost of lubricating oil, filter and grease - The quantity of lubricating oil, filter and grease required depends on: operating hours, frequency of changes, engine characteristics, working conditions at the job site, and maintenance practices in the company.
  16. 4. Tire Cost - The cost of pneumatic tires (rubber tires) is considered as a part of operating cost. The life of tires varies according to extent of wear it is subjected to, which depends on the job site conditions. 5. Equipment operator wages - includes the company's hourly wages and benefits paid to the operators. 6. Cost of replacing high-wear items - The high-wear items include blades, cutting edges, drill bits, bucket teeth etc. 7. Cost of mobilization, demobilization and assembly - includes transportation charges from one project site to another, cost required for getting road permits, unloading charges, cost of assembly at the project site etc.
  17. 3 DIFFERENT METHODS TO ACQUIRE CONSTRUCTION EQUIPMENT FOR A PROJECT 1. Buying - results in direct ownership of the equipment. 2. Renting - is a method of acquiring the equipment for a short duration. 3. Leasing - is another method of acquiring the equipment, for a longer period of time.
  19. ROCKS Rocks are made of one or more minerals. There are three main classifications of rock, based on the way the rock was formed: sedimentary, metamorphic and igneous.
  20. ENGINEERING PROPERTIES OF ROCK Engineering properties of rock are controlled by the discontinuities within the rock mass and the properties of the intact rock. Therefore, engineering properties for rock must account for the properties of the intact rock and for the properties of the rock mass specifically considering the discontinuities within the rock mass. Rock properties can be divided into two categories: • Intact rock properties • Rock mass properties
  21. SOIL Soil is formed of fine rock particles mixed with air, water and particles from dead plant and animal matter. There are three main types of soil which are classified according to the amount of sand and clay in them.
  22. ENGINEERING PROPERTIES OF SOIL 1.) Laboratory Index Property Testing Laboratory index property testing is mainly used to classify soils, though in some cases, they can also be used with correlations to estimate specific soil design properties. 2.) Laboratory Performance Testing Laboratory performance testing is mainly used to estimate strength, compressibility, and permeability characteristics of soil and rock. For rock, the focus of laboratory performance testing is typically on the shear strength of the intact rock, or on the shear strength of specific discontinuities (i.e., joint/seam) within the rock mass. See Soil shear strength may be determined on either undisturbed specimens of finer grained soil (undisturbed specimens of granular soils are very difficult, if not impossible, to get), or disturbed or remolded specimens of fine- or coarse-grained soil.
  23. INFLUENCE OF EXISTING AND FUTURE CONDITIONS ON SOIL AND ROCK PROPERTIES Many soil properties used for design are not intrinsic to the soil type but vary depending on conditions. In-situ stresses, changes in stresses, the presence of water, rate and direction of loading, and time can all affect the behavior of soils. Prior to evaluating the properties of a given soil, it is important to determine the existing conditions as well as how conditions may change over the life of the project. Some construction materials such as weak rock may lose strength due to weathering within the design life of the embankment. These long-term effects shall be considered when selecting properties to use for design.
  24. METHODS OF DETERMINING SOIL AND ROCK PROPERTIES Subsurface soil or rock properties are generally determined using one or more of the following methods: • In-situ testing during the field exploration program; • Laboratory testing, and • Back-analysis based on site performance data The two most common in-situ test methods for use in soil are the Standard Penetration Test, (SPT) and the cone penetrometer test (CPT)
  26. MOBILE EQUIPMENT POWER REQUIREMENTS The constructor must select the proper equipment to relocate and/or process materials economically. The analysis procedure for matching the best possible machine to the project task requires inquiry into a machine’s mechanical capability. The engineer must first calculate the power required to propel the machine and its load. This power requirement is established by two factors: 1. Rolling Resistance 2. Grade Resistance Equipment manufacturers publish performance charts for individual machine models. These charts enable the equipment planner to analyze a machine’s ability to perform under a given set of job and load conditions
  27. Payload • The payload capacity of construction excavation and hauling equipment can be expressed either volumetrically or gravimetrically. • Volumetric capacity can be stated as struck or heaped volume and either volume can be expressed in terms of loose cubic yard, bank cubic yard, or compacted cubic yard. • The payload capacity of excavation buckets and hauling units is often stated by the manufacturer in terms of the volume of loose material, assuming that the material is heaped at a specified angle of repose. Machine Performance Cycle time and payload determine a machine’s production rate, and machine travel speed directly affects cycle time.
  28. REQUIRED POWER It is the power required is the power needed to overcome resisting forces and cause machine motion. The forces resisting the movement of mobile equipment are: a. Rolling Resistance - The resistance of a level surface to constant-velocity motion across it. b. Grade Resistance - The force-opposing movement of a machine up a frictionless slope. Total Resistance Therefore, power required is the power necessary to overcome the total resistance to machine movement, which is the sum of rolling and grade resistance. Total Resistance(TR) = Rolling Resistance(RR)+Grade Resistance(GR)
  29. AVAILABLE POWER • Internal combustion engines power most construction equipment. • Because diesel engines perform better under heavy-duty applications than gasoline engines, diesel powered machines are the work horses of the construction industry. • Diesel engines have longer service lives and lower fuel consumption. • Diesel fuel presents less of a fire hazard.
  30. Work and Power Work is defined as force through distance. Work = Force * Distance Torque An internal combustion engine by the combustion of fuel in a piston develops a mechanical force that acts on a crankshaft having a radius r. The crankshaft in turn drives the flywheel and gears that power the other components of the machine. The force from a rotating object, such as crankshafts (a "twisting" force), is termed torque.
  31. Horsepower Rating • Manufacturers rate machine horsepower as either gross or flywheel (sometimes listed as net horsepower) • Gross horsepower is the actual power generated by the engine prior to load losses for auxiliary systems, such as the alternator, air conditioner compressors, and water pump. • Flywheel horsepower (fwhp) can be considered as usable horsepower. It is the power available to operate a machine-power the driveline-after deducting for power losses in the engine.
  32. USABLE POWER Usable power depends on project conditions: primarily, haul- road surface condition, altitude, and temperature. Usable force = Coefficient of traction*Weight on powered running gear