3. Frame
consists of upright load bearing members such as posts in
timber, columns in concrete or stanchions in steel which
are arranged at the corners of the square or rectangular
base
transfer loads of heavy structure plus any imposed loads
via the frame structure members to a suitable lower
ground
4. concrete
Plain: mixture of cement, fine & coarse aggregate & water
Increases its strength during curing / hardening period
Portland cement is used – 28days
Nominal max sizes of aggregates: 40, 20, 14 and 10mm;
5mm is for precast products
Grade 7 & 10 - plain unreinforced concrete
Grade 15 & 30 – RC with lightweight aggregates
Grade 25 – RC with dense aggregates
Grade 30 to 50 – pre-stressed concrete
Eg: strength of Grade 10 = 10.0 N/mm2
5.
6. Reinforcement
Requirements:
Capable of achieving tensile strength without any undue
strain
A material can be easily bent to any required shape
Surface must be capable of developing adequate bond
between the concrete & reinforcement
Reasonable cost & acceptable to overall design concept
steel in the form of bars
mild steel (R) & high yield (T)
strength: 250 N/mm2 & 460 N/mm2
nominal sizes: 6, 8, 10, 12, 16, 20, 25, 32mm
11. Fabric reinforcement
Structural members that require only small area of
reinforcement can be reinforced by steel fabric, which
can be supplied by sheets / rolls
Factory-made by welding
Sheets: 4800mm x 2400mm
Rolls: 48.00m & 72.00m with a common width of
2.40m
Total cross sectional area of main bars in mm2
12. Formwork
A mould / box into which wet concrete can be poured
so that it will flow & finally set to the inner profile of
the box
Requirements:
Strong enough to support the load of wet concrete
Must be accurately set out
Have grout-tight joints – grout leakage can cause
honeycombing of the surface
Designed to be the max size that can be easily handled
by hand & mechanical lifting device
Can be easily fixed using ?
Moisture content btw 15 – 20%
16. STUMP
A short column constructed on top of the pad
foundation / pile cap to support ground beam &
column above
to transfer the load of a building onto the pad
foundation / pile cap
to raise ground beam & ground floor slab to the
required height above GL
Basic elements:
Reinforcement
Formwork
concrete
17.
18. Beams
supporting walls, joists, etc., at or near ground level,
itself either resting directly upon the ground or
supported at both ends by piers.
used in situations where foundation walls may not be
achievable
Vary in their complexity of design & reinforcement
depends on loading
erected over columns or piers taken into the soil
Transfer their loadings to columns
When erecting them, the piers must be already cast in
the ground
19. Beams
Clearing the ground
Blinding layer
reinforcements are then tied and bent
separately; carried and laid over the columns
and blinding
Formwork erected to sides
concrete is prepared and poured
20.
21.
22. Columns
Constructed from either plain concrete (1:3:6) /
reinforced concrete (1:2:4)
vertical structural element that transmits, through
compression, the weight of the structure above to other
structural elements below
to support beams or arches on which the upper parts of
walls or ceilings rest
Columns must be properly located, and the choice of a
steel beam or wood beams
23.
24.
25. Process
Superstructure
Tie up all rings around and into
vertical steel bars according to design.
Fix form work of required size with
vertical steel bars.
Lay cement concrete
Foundation
Excavation
Steel bar, formwork, concrete to
footing
26.
27.
28. Link tied to main bar Adding spacer block
lappingWood bracing
29. Sometimes, we use steel formwork
Group Activity: Compare the
advantages of timber & steel formwork
