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CONSTRUCTION

TECHNOLOGY II

CHAPTER 2

PRELIMINARY WORKS

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Preliminary works- Site works that are

preparatoryand subsidiaryin nature, carried outbefore the actual construction work is executed

Site Preparation

Site clearance

Earthwork

Site surveying Demolition

Temporary Facilities

Site office

Accommodation, toilet & sanitary

Storage

Security

Laboratory

Services

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2.1 Site Preparation

Site clearanceHas to be donebeforethe

construction, clearing undergrowth, bushes,grubbing up & removal of tree roots

Earthwork

Work below grounde.g. foundation

The top layerof the soil is an unsuitablematerial

Shall be removedandbackfilled

Earth drain construction, construction of accessroad, levelling of the ground to the required

platform level

Site surveyingDetermine theboundaryof the siteand levelling for building, drainage, road, services

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2.1 Site Preparation (Contd)

Demolition

If there is any existing structureto be demolished

Taking downpartial demolition of a structure &normally to be carried out using hand tools

Requires a good comprehensive knowledgeofbuilding

constructionand design, so that load bearing structurescan be identified & supported by struts, props, shoring

Demolitioncomplete removal of a structure

A detailed surveyand examinationof the structure

should be made The condition of the adjoining propertieswhich may be

affectedby the demolitionshould be considered

Flammablematerials are removedbefore the demolition

works commences

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2.2 Temporary Facilities

Site Office

Timber huts

Wall - waterproofing plywood nailed onto sawn

hardwood timber as stud (vertical) & noggings

Rooflightweight material (zinc or metal sheeting) Normally for a shortconstruction period

Mobile cabin or container

Available in a wide variety of sizes& styles& fully

equipped Convenient for transportationby using trailer

Is durable& allow for re-useon other sites for many

years

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2.2 Temporary Facilities (Contd) Accommodation, toilet and sanitary fittings

Site personnelwho are stationed on site

Foreign laboursthroughout the entire construction periods

Storage

Types of storage facilities depends on durability,vulnerability to damage & vulnerability to theft

Ironmongery, hand toolsandpaint to be kept in lock hut

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Cement,plasterand limein

begrequire a drystore

Aggregatessuch as sandand

gravelrequire a clean firm base

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Bricksandblocksshould be

stackedin stable piles on a level

& well-drainedsurface

Roof tileshave a greater

resistanceto load when it is

imposed on the edge

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Timberis a hygroscopic

material and therefore to

prevent undue moisturemovement

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2.2 Temporary Facilities (Contd)

Security

Spotlight, hoarding, fencingand guardhouse

Artificial lighting

Reduces the risk of accident and injury

Increases the production hour on site, allowwork to proceed at night

Deliveries and collection of materials or plantcan be made outside normal site working hours

Improve the general security on site

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2.2 Temporary Facilities (Contd)

Laboratory

A place for testingof the materialon site

Eg, cube test for concrete, tensile test for steel

Which is essential under certain government

projectsof infrastructureworks Services

Waterconcreting, plastering and painting

Electricityto provide the power to drive small

and large items of plant, provide lighting Electricityportable self-powered generators &

metered supply from the local area electricityboard

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2.2 Temporary Facilities (Contd)

Fencing Fencing is used to define the limit of the site or

compoundand toprevent theft and vandalism

A fencecan be constructed to provide aphysicalbarrier of solid construction or visual barrier of

open work construction Type of fencing depends on the degree of security,

cost implication, type of neighbourhood, durationof contract

A security fence around the site or compoundshould be at least 1.8m high above the ground

It should include the minimum number of accesspoints which should have a lockable barrieror gate

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2.2 Temporary Facilities (Contd)

Hoarding

Hoarding is close boarded fenceserected

adjacent to a highwayorpublic footpath

It can prevent unauthorised personobtaining

accessto the site It provides a degree ofprotectionfor thepublic

from the dustand noiseassociated with the

construction works

There are two forms of hoardings in common

use; vertical hoardingand fan hoarding

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2.2 Temporary Facilities (Contd)

Vertical hoarding

Consists of a series of closed boarded panels

securely fixed to resist wind loads & accidental

impact loads

Can be free standing or fixed by stays toexternal walls of existing structures

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2.2 Temporary Facilities (Contd)

Fan hoarding

Is placed at a level above normal traffic height

Arranged in a manner that any falling debris is

directed back towards the site

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