CONSTRUCTION

1. CONSTRUCTION

2. Construction Systems • Early people lived in caves or in the brush --- teepees from animal hides were used • Wood, stone, mud and straw were used in construction • The Egyptians built the largest pyramid of almost 500 feet length and made of over two million blocks of limestone, each weighing more than a ton --- 5000 years ago • The Romans started building aqueducts, sewer systems in about 300 BC • One of the greatest contribution of the Romans is the use of arch • Construction means building a structure at the place where it will be used --- construction site • The usable structures in construction are building, bridge, dam, road, and tunnel.

3. Resources for Construction • People • They are needed to design, engineer the structureand to manage the business of construction • Landowner decides that there is a need for a structure • Architects design buildings. They plan how to build a structure and where to place it on the site • Civil engineers work with architects to prepare drawings and to design and foundation • Civil engineers also give details about utilities --- plumbing, heating, air conditioning, and electrical wiring • Structural engineers plan the building’s structure --- it should be strong enough to carry the desired load • General contractors own their own construction companies • Estimators work for the contractor --- prepare a proposal of cost and specifications called a bid

4. Resources for Construction • People • Project managers make sure construction is carried out properly and meets building codes • Tradespeople include carpenters, electricians, plumbers, and masons • Information • Information takes the form of plans, bids and specifications • Specifications includes the type of material to be used and the way the foundation will be built • Architects have mechanical and architectural drawings • Engineers have information about building materials and loads the structure will support

5. Resources for Construction • Materials • Concrete, lumber(wood), steel, glass and brick • Concrete is made from stone, sand, water and cement • Cement is a mixture of limestone and clay • Molds of lumber called forms are used to make different shapes from wet concrete • Steel rods/meshes are used to reinforce the brittle concrete • Lumber is used to provide the framework of homes • Steel is used for the framework of skyscrapers, bridges, and towers • Glass lets the light in and adds to the beauty of the structure • Bricks made from clay are made in an oven called a kiln

6. Resources for Construction • Tools and Machines • Special equipment is used for excavating (digging), lifting heavy materials • Robots are useful in dangerous jobs • Energy • Construction systems use energy to operate machines and tools • Producing material for construction and transporting to the site consumes energy • Capital • A loan for a home is called a mortgage --- paid back over a period of years with interest • Interest is the fee the back charges for the loan

7. Resources for Construction • Time • Air-driven staple guns are replacing hammers and nails • Parts of a structure can be prefabricated in a factory • Modular construction is being used more and more often

8. Selecting the Site • Land costs can vary from one place to another • Grading(leveling) is needed in hilly areas • Transportation needs have to considered to deliver/ship the goods to the site • The environment must be preserved --- airport • Water and electricity must be available

9. Preparing the Site • Unwanted buildings must be removed • Wrecking balls or explosives are used to demolish buildings • A surveyor marks the site to show where the structure will be built • A transit is used to measure and lay out angles • An engineer’s level is used to set the elevation of different points