BACHELOR OF QUANTITY SURVEYING (HONS)

BLD 60104 CONSTRUCTION TECHNOLOGY 1

By Azrina Md Yaakob Azrina.MdYaakob@taylors.edu.my

CHAPTER 2

SITE AND TEMPORARY WORKS

1.0 CHOICES OF SITE

Site Investigation

Accessibility to Site

Water Table

Subsoil Services

Available Facilities

•  Any existing road to the site? Do you need temporary roads?

•  Condition of the road?

Ø Width Ø Gradient Ø Bends Ø Sharp corners

1.1 ACCESSIBILITY TO SITE

1.2 AVAILABLE FACILITIES Look what you have around your site, such as: •  Shops

•  Town

•  School

•  Police / fire station

•  Hospital / clinic

•  Bus / taxi station

1.3 SERVICES •  Any underground services running? If yes, need to take necessary

action before constructing a building.

•  Example of services:

Ø water mains Ø electricity cables Ø sewer (pipes) Ø petrol station

1.4 WATER TABLE •  The level at which the groundwater pressure is equal to atmospheric

pressure

•  Building erected above the highest groundwater level

1.4 WATER TABLE (CONT’D)

•  Groundwater exists below the water table, which divides unsaturated soil & rock from saturated.

1.5 SUBSOIL (TYPES)

•  Loose •  Subject to

movement

•  Good bearing capacity

•  Does not drain well •  Take the foundation

down at least 1m below ground level

•  Ideal subsoil •  Strong and

easily drained

•  Good foundation •  High excavation cost

Hard Rock Gravel

Sand Clay

1.6 SITE CLEARANCE •  Demolition of existing building; either hand or rapid destruction

•  Removal of bushes and trees

•  Removal of soil to reduce level

•  What types of plants is used for demolition?

Ø Back-hoe, lorries, bulldozer, crane, tractor, scraper, barrow?

1.7 SITE SETTING OUT Es

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Each corner being marked with a stout peg Check on right angles & correct lengths

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Foundation trench positions and walls

1.8 TEMPORARY WORKS 1.8.1 ACCOMMODATION FOR WORKERS

1.8.2 MATERIAL STORAGE

Types depend on durability, vulnerability to damage and vulnerability to theft:- ü Cement, plaster, lime : dry store free from draughts which

can bring in moist air

ü  Aggregates : clean firm base to ensure foreign matter is not included when extracting material from the base of the stockpile

ü  Bricks & blocks : to be stacked in stable piles on a level & well-drained surface; covered with polythene sheets

ü Roof tiles : to be stacked in pairs, head to tail, to give protection to the nibs.

1.8.2 MATERIAL STORAGE

a)  Fencing •  2 functions:

i)  defines the limit of site & compound ii)  deterrent to trespasser

•  Types depend on the degree of security required, cost, neighborhoods and duration of contract

•  At least 1.80m high above ground

1.8.3 SECURITY

b) Hoarding •  Close-boarded fence to prevent unauthorized persons access

to site

i.  Vertical hoarding –close-boarded panels to resist wind loads, Free standing / fixed by stays to external wall

ii.  Fan hoarding –give protection from falling object,

placed at a level above the normal traffic

1.8.3 SECURITY

1.9 SCAFFOLDING •  A temporary structure from which persons can gain access to a place of

work

•  3 forms:

a) putlog scaffold

b) independent scaffold

c) mobile access tower

•  Material: tubular steel, tubular aluminium alloy & timber

•  Tubular steel: tubes of 48mm dia with a nominal 38mm dia; galvanised & ungalvanised; 3 times heavier than aluminium alloy, stronger, for longer span

•  Aluminium alloy: 48mm outside diameter; no protective treatment is required unless to be in contact with wet cement / sea water which can cause corrosion –bitumastic paint

•  Timber: rarely used; members are lashed together with wire / rope

1.9.1 PUTLOG SCAFFOLDING

•  Consists of a single row of standards set away from wall at 1.25 / 1.30m

•  Standards are joined together with horizontal members –ledgers & are tied to the building with cross-members –putlogs

•  Erected as the building rises; used mostly for brick construction

•  Partly supported by the building

•  2 rows of standards at about 1m apart which tied by cross-members –transoms

•  Does not rely upon building for support

1.9.2 INDEPENDENT SCAFFOLDING

1.9.3 MOBILE ACCESS TOWER •  Gaining access to buildings for maintenance and repair

•  Preferred to conventional scaffold…why? •  Assembled from prefabricated components

•  Move manually on ground

•  Free-standing

•  Having dimensions to a predetermined design

•  At least 1 platform to work from

•  At least 4 legs; each is fitted with castor

•  Platform is accessed by a ladder which is firmly attached, should not touch the ground, 1strung not more than 400mm above the ground

1.10 TIMBERING •  To cover temporary supports to sides of excavations

•  Planking & strutting

•  Amount of timbering depends on: depth of excavation & nature of soil to be upheld

1.10.1 TIMBERING MAIN COMPONENTS

•  Poling boards: 1.00 –1.50m in length; vary in cross-section 175 x 38 –225 x 50mm; placed vertically & abut the soil at sides of excavation

•  Walings: running the length of trench & support poling boards; 175 x 50 –225 x 75mm

•  Struts: square; 100 x 100 or 150 x 150mm; support walings; spaced at about 1.80m centres to allow adequate working space between them

TUTORIAL 2 •  You are currently working as a contractor in a

construction firm. You are required to perform a presentation to your boss and client highlighting the issues that need to be taken into consideration before constructing a building. Clearly highlight the issues and explain the condition.

•  Besides that, list down all temporary works that you think it is important for that particular site.

Requirements:

You should prepare the presentation in powerpoint format. Maximum slide is 15. Each presentation must state the name, student ID and title of presentation. (Group of 5)