TOPIC 1.2

FORCES ON CIVIL ENGINEERING

PROJECT

FORCES ON CIVIL ENGINEERING

PROJECT

BY :NOR AZAH BINTI AZIZ

KOLEJ MATRIKULASI TEKNIKAL KEDAH

FORCES ON CIVIL ENGINEERING PROJECT

FORCES ON CIVIL ENGINEERING PROJECT

LEARNING OUTCOMES :

In any building design, the strength and stability of an overall building and its individual components must be considered.

This involves structural calculations to work

out the effects of all the forces acting on any component in the building and on the

building overall.

To do this we need to resolve the forces in the system to see what the overall effects

are likely to be.

INTRODUCTIONINTRODUCTION

An overview of the many different forces acting on a building.

INTRODUCTIONINTRODUCTION

A summary of all the forces acting on the building.The dotted arrow is the resultant force,a force representing the overall effect of the loads.

INTRODUCTIONINTRODUCTION

INTRODUCTIONINTRODUCTION

Examples of Typical StructuresExamples of Typical Structures

TYPES OF PHYSICAL FORCESTYPES OF PHYSICAL FORCES

Dead loads are permanent or stationary loads which are transferred to structure throughoutthe life span.

Dead load is primarily due to- self weight of structural members

- permanent architectural component such as exterior cladding, partitions and ceilings

- equipment and static machinery when permanent fixtures

i) DEAD LOADi) DEAD LOAD

Tension

Compression

Loads

A Simply Supported BeamA Simply Supported Beam

ii) LIVE LOAD/IMPOSED LOADii) LIVE LOAD/IMPOSED LOAD

EXAMPLEEXAMPLE

Towers: Live and Dead Loads

Towers serve many purposes. Radio, TV and wireless communication signals are transmitted from towers. Forest rangers keep a vigilant eye peeled for signs of forest fires from observation towers. Skyscrapers serve an important role in the world’s urban areas.Like other structures, towers are subjected to dead and live loads. In the case of a skyscraper, dead loads are comprised of steel columns and beams, concrete, and glass – the weight of the structure itself. Live loads include the people milling about on the floors and ascending the elevators; plus furniture, materials, and goods that move into the building.Another important live load acting on a skyscraper is the force of wind blowing against the exterior surfaces. Because the buildings have an enormous amount of surface area, the force of wind on a skyscraper can be extremely powerful.

ii) TRAFFIC LOADii) TRAFFIC LOAD

Traffic Force Transfer Example - Bridge

*Front axle: 8,000 lb x 45/60 = 6,000 lb Rear axle: 32,000 lb x 30/60 = 16,000 lb

8,000 lb 32,000 lb

22,000 lb* 18,000 lb**

L = 60 ft

30 ft 30 ft

15 ft 45 ft

**Front axle: 8,000 lb x 15/60 = 2,000 lb Rear axle: 32,000 lb x 30/60 = 16,000 lb

ii) LATERAL EARTH PRESSUREii) LATERAL EARTH PRESSURE

Lateral Support

In geotechnical engineering, it is often

necessary to prevent lateral soil movements.

Cantilever retaining wall

Braced excavation

Anchored sheet pile

Tie rod

Sheet pile

Anchor

We have to estimate the lateral soil pressures acting on these structures, to be able to design them.

Gravity Retaining wall

Soil nailing

Reinforced earth wall

Lateral Support

Soil Nailing

Reinforced earth walls are increasingly

becoming popular.geosynthetics

Lateral Support

Crib Wall have been used in Queensland.

Interlocking stretchers

and headers

filled with soil

Good drainage & allow plant growth.

Looks good.

Lateral Support

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Reinforced earth wallsReinforced earth walls are increasingly becoming popular.

geosynthetics

Lateral Support

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Crib wallsCrib walls have been used in Queensland.

Interlocking stretchers and headers

filled with soil

Good drainage & allow plant growth.

Looks good.

Lateral Support

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Retaining Walls - Applications

Road

Train

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Retaining Walls - Applications

highway

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Retaining Walls - Applications

basement wall

High-rise building

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Gravity Retaining Walls

cobbles

cement mortarplain concrete or stone masonry

They rely on their self weight to support the backfillThey rely on their self weight to support the backfill

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Cantilever Retaining Walls

They act like vertical cantilever, fixed to the ground

They act like vertical cantilever, fixed to the ground

Reinforced; smaller section than gravity walls

Soil exerts pressures on retaining structures

ii) HYDROSTATIC PRESSURE/ WATER PRESSURE

ii) HYDROSTATIC PRESSURE/ WATER PRESSURE

Dam Structure

Arch Dam Cross Section

Environmental Forces

Forces that acting to engineering structure due to

environmental factor

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i) Wind Load

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i) Wind Load

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i) Wind Load

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ii) Earthquake

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ii) Earthquake

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iii) Waves Load

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iv) Flood

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