Construction Technology Applying Technology Period 1

Construction Technology ► The design and building of structures ► Some structures have been so beautifully designed that they are considered great works of art and other structures have become important historical or cultural symbols while others have ended up as disasters.

Structures ► Something that is constructed or built. ► Are made by joining parts to meet a certain need or perform a certain task.  Structural Member- building material used with similar materials to make a structures frame ► Can be natural or human-made  Natural ex: spider web, birds nest, wasp nest,… ► The design of any structure depends on its use

Construction Systems Model Inputs: People Information Materials Tools/ Machines Energy Capitol Time Processes: Designing the structure Preparing the site Laying the foundation Building the structure Outputs: Finished Structure Impacts on individuals, community and environment Feedback: Comments from structures users or inhabitants Accidents or disasters resulting from defective materials or poor design

Who Designs Structures? ► Civil Engineers- design and supervise the building of structures that service the public  Most work on roads, water supply, sewers, and some public structures ► Structural Engineers- civil engineers whose work focuses more on the mechanics of load- bearing structures ► Architect- someone who designs buildings and often over sees construction

Designing Structures ► On large projects, structural engineers and architects work together. The architect designs a building, and the engineer determines what kind of structural system is needed. The engineers decide what sizes and types of columns and beams are needed to make the structure stable. They consider the forces that act on a structure as well as some other questions to be considered: ► How many vehicles or pedestrians will travel on the bridge daily ► How might a skyscraper be affected by high wind? ► What needs to be done to protect a structure being built in an area with frequent earthquakes?

Forces on Structures ► Structures must be designed to withstand the forces that will act on them. ► Force- a push or a pull that transfers energy to an object ► Forces can be external or internal  External- come from outside the structure  Internal- those that one part of the structure exerts on another part. They are forces acting within a structural material

Forces on Structures Internal Forces ► Tension: stretches an object or even pulls it apart ► Compression: Shortens an object or even crushes it. Squeezing force ► Torsion: Twist an object along its axis ► Shear: Pushes adjacent parts of a material in opposite directions

Forces on Structures External Forces ► A load is an external force acting on an object.  A load on a structure can be any kind of weight  Can also be force caused by pressure from wind or water ► Two types of loads:  Static  Dynamic

Static Load ► Also known as a “dead load” ► Changes slowly or not at all ► The materials used to build a structure are part of this load  ex: bricks in a building, twigs in a birds nest, shingles on a roof

Dynamic Loads ► Also known as “live loads” ► These loads move or change  Ex: cars or people crossing a bridge, oil flowing through a pipeline, or wind blowing on a building

Types of Construction Projects ► Each construction project falls into one of the major types of construction:  Residential  Industrial  Commercial  Public Works

Residential Construction ► Building of structures in which people live.  Most of these structures are single-family, private homes, condo’s or even multi-family units or apartments. ► Most of this construction is done by fairly small construction companies. ► Stick Construction- small and lighter pieces of wood are assembled into a framework which is then covered with other building materials to make the walls, floors, and roof.  method started many years ago and still greatly used today

Industrial Construction ► The building of manufacturing plants and other industrial structures.  Usually planned by specialized engineering firms and usually built by large construction firms that have many employees.

Commercial Construction ► Building structures that are used for business.  Supermarkets, malls, restaurants, office buildings, and skyscrapers ► Usually large scale construction projects that involve millions of dollars and many workers. ► Building materials and techniques used in commercial and industrial construction are somewhat different from those in residential construction.  These structures often have steel frames and many concrete parts

Public Works Construction ► Building structures intended for public use or benefit.  Includes large projects ► Dams ► Highways ► Bridges ► Tunnels ► Hospitals ► Schools ► Airports ► Sewer systems

Types of Structures ► Buildings  Usually defined as a structure with a roof and walls  May be temporary or permanent ► Roads  Highways, streets, and other roadways  Highways- major roads through and around cities. Usually vary in width from 2-8 lanes  Interstates HW- pass thru more than 1 state

Types of Structures ► Tunnels  Underground passageway built to allow people, vehicle or materials to pass through or under an obstruction ► Also can be built to carry water around a dam  Three types of tunnels ► Earth- dangerous to build, constructed in soil or sand ► Immersed- pre-manf. sections that are floated to site then sunk into trenches and all connected together ► Rock- blasted or drilled through rock with machines

Types of Structures ► Dams  Structure placed across a body of water to control or block its flow ► Water that collects behind a dam is called a reservoir  Usually built from earth, concrete, steel, masonry, or wood but normally a combination of materials is used.  Main reason for dams is to provide a dependable water supply for nearby communities

Types of Structures ► Canals  Artificial waterways built for irrigation or navigation ► Bridges  Built to allow people and vehicles and anything else to pass over something else ► Often built over water, valleys, highways, or railroad tracks