ARE 234 Construction Methods: Planning & Site Layout

• ARE 234 covers Construction Methods and Equipment
• Builders Plants & Site Equipment are covered in parts I & II
• The lectures include Planning for Building Construction, Builders Plants & Equipment, Equipment Costing, Site Equipment, and Concreting Equipment

Planning

• Planning drives success in building construction
• "Fail to Plan, Plan to Fail" is a key idea
• "Measure Twice, Cut Once" is a key idea
• Planning includes material procurement, sequencing of operations, managing site logistics and project schedule, as well as technical aspects
• Urban projects must mitigate nuisances to neighbors
• Various pieces of equipment support construction processes
• Concrete placement booms are an example

Site Layout

• Contractors must consider many factors for site layout to support operations
• Site size is compared to building size and configuration
• Effective and efficient operation for subcontractors is enabled by site layout

Builders Plants & Equipment

• Construction equipment increases production, reduces costs, and is used for activities that can't be done manually.
• Equipment eliminates heavy manual work, reduces fatigue, and increases productivity.
• Equipment replaces labor where there are personnel shortages with necessary skills.
• Equipment maintains the high standards required, particularly in structural engineering works.
• Economic considerations state that plant must be fully utilized and not left standing idle.
• Full utilization of plant is usually considered in the region of 85% of on-site time for routine maintenance
• Maintenance is needed to avoid plant breakdowns that disrupt the construction schedule
• Multiple plant items work together, so a correct economic balance is important
• Skilled mechanics may be needed on large contracts for daily, preventive maintenance tasks

Equipment Costing

• Plant can be bought or hired, or a combination of both
• Plant choice is governed by economic factors and possibility of being used on future sites
• Plant can be hired for short periods
• Repairs and replacements of hired plant are the hire company's responsibility
• Hired Plant is returned to the hire company after use, relieving the contractor with disposal issues.
• Hired plant can be used with the operator, fuel, and oil included in the hire rate.
• Plant availability of bought plant is totally within the contractor's control
• Hourly cost of bought plant is generally less than hired plant
• The owner has a choice of costing method used.
• All items of plant have optimum output and cycle times which can be the basis for estimating productivity
• Productivity is measured during timed observations, feedback information, or published tables contained in manufacturer's literature/textbooks

Site Equipment- Earth Moving Equipment

• Bulldozers are used for shallow excavations up to 300 mm deep as well as clearance of shrubs and trees, towing and pushing other machines
• Scrapers consist of a scraper bowl. which is lowered to cut and collect soil where stripping and leveling is required
• When the scraper bowl is full the apron at the cutting edge is closed to retain the earth and raised for travelling to the disposal area.
• On arrival at disposal the scraper bowl is Lowered, the apron is opened and the spoil pushed out by the tailgate
• Graders are similar in concept to bulldozers but with adjustable blade to finish or grade the upper surface of a large are
• Graders do not have the power of a bulldozer so are unsuitable for over-site excavation work.
• Tracked tractor shovel are more suitable for wet and uneven ground conditions
• Wheeled tractor shovel have greater speed and maneuvering capabilities.
• Tractor shovels can be fitted with a four-in-one bucket.
• Excavating Machines is one of the major items used for builders' plant equipment to excavate and load most types of soil.
• Universal Excavators category covers most forms of excavators, utilizing a power unit, a tracked-based machine , a slew capacity of 360.
• Purpose-Designed Excavators are machines designed to carry out one mode of excavation and hydraulically controlled with a shorter cycle time.
• Multi-purpose Excavators are machines can perform several excavating functions, having both front and rear attachments.
• Skimmers are excavators rigged using a universal power unit for surface stripping and shallow excavation work up to 300 mm deep where a high degree of accuracy is required.
• Face Shovels primary function is to excavate above its own track or wheel level and can excavate any type of soil except rocks.
• Backacters are suitable for trench, foundation and basement excavations and spoil can be placed alongside used in backfilling.
• Draglines are based on the universal power unit using a crane rigging to which is attached a drag bucket.
• Designed for bulk excavation in loose soils up to 3000 mm below using a grab or clamshell bucket for excavating in very loose soils
• Multi-Purpose Excavators are fitted with a loading/excavating front bucket and a rear backacter bucket
• Haulage Vehicles convey passengers and/or materials between building sites
• Vans range from transporting two people plus a limited amount of materials to those that carry large sheets of glass.
• Passenger Vehicles range from a simple framed cabin on a lorry to a conventional bus or coach.
• Lorries are referred to as haul vehicles available as road-or site-only vehicles
• The off-highway or site-only lorries are can carry two to three times the axle load allowed on the public highway.

Site Equipment - Transport Vehicles

• Dumpers are for horizontal transportation of materials on and off construction sites.
• Highway dumpers are used to carry materials such as excavated spoil along the roads.
• There are dumpers with front tipping, side tipping, or elevated tipping facilities. -ForkLift Trucks are used for the for horizontal and limited vertical transportation of materials on pallets or banded together
• They are suitable for construction sites where the building height does not exceed three stories using three basic types
• Materials Hoists are designed for one specific use and can be a mobile format which can be dismantled. Regulations state that enclosures and gates at least two meters high should protect counterweight from ground levels
• Micro-switch feature is on gates to operated until the gates are closed and to prevent the gates in between landings
• Passenger hoists have the cage to retain occupants by debris
• Material should be restrained to spill, and loads should be contained Material loads Transport vehicles-Passenger Hoists are designed to carry passengers capable of transporting a load
• Rubble Chutes apply to contracts for demolition, maintenance and can be produced from reinforced rubber with chain linkage for continuity
• Unit lengths are generally 1100mm, providing an effective length of 1m.
• Hoppers and side entry units are made for special applications

Site Equipment - Cranes

• Cranes are lifting equipment that raise materials and move the load horizontally and can be mobile, static ad tower cranes
• Gantry Cranes consist of two `A' frames joined together with a cross-member on which transverses the lifting appliance.
• Large gantry cranes (up to 100 tones capacity) have bogies running on rail tracks, small gantry cranes are used primarily for loading
• Medium/ Large gantry cranes have three directions movement e.g moving along the cross-beam, raising, by forward and reverse movements of whole gantry crane

Concreting Equipment

• Concrete activity consist of receiving on site, Storage of materials is carried out in small batches only using held tools
• Transport ranges from a simple bucket to barrows ad dumpers, using crane skips at high level
• This includes Placing -Placing the wet concrete in the, formwork excavating area and using vibration Concreting Plant needs three activity headings such as Mixing, Transporting and Placing
• Concrete Mixers have a rotating drum designed to produce concrete without segregation of the mix

Concrete Material

• The factors to be, type concrete mixer factors such as maximum output total output. Type and method of, concrete, type and, height are require
• There are different models using a batch mixing five per cycle 12 per batch can can be output 200 Litres with achieve through, batches small transportation, with Small Mixers, per batch wheelbarrow, an hourly placing rate of 2-3m³ for
• Batch The mostly, batch mixers, batch are and loaded to is hand the control regulate. the mixes Small is of The for The 200-750 Non with can can of weight quality drum small integral is litres better and Better integral loading mixers is generally quality tanks. and better quality tanks. are
• Concrete is transported using the capacity mixer using small transports to wheelbarrow the between minimum plank. the is and, transport the mixers positions.

Concreting Equipment : Concrete Transport

• Dumpers transport mixers up to 600 per transport the to and in use with a between and is that Concrete in can 4m3 to be Concrete
• Concrete: pump with concrete into pumps requires minute special coating a small the that water, and-curing factory acrylic for electric to sealed Steaming Curing
• Compaction involves filling the mould, for correct inserts use vibration Concrete for reinforcement Concrete with rods the Finally Concrete that: Concrete that
• Poker 75 vertically head into the of contains that
• Clamp electricity machines surface, concrete with is is steam use
• Finish is is required is. is:
• water- water- water- content content water. with the Concrete used
• with is The with with will Setting