Pre-fabricated Concrete

8/12/2019 Pre-fabricated Concrete

1/41

LECTURE ON PRE-CAST CONCRETE

1

Pre-Cast (also known as Pre-Fab)Ar. SERGE T. CHUA, Jr. fuap M_Arch CTM Sr MRIAS

Associate Professor II


2/41

2

INTRODUCTIONINTRODUCTION

The concept of precast (also known asprefabricated) construction includesthose buildings where the majority ofstructural components are standardizedand produced in plants in a location awayfrom the building, and then transported to

the site for assembly.HISTORYHISTORY

Ancient RomansAncient Romans invented and used concrete extensively Developed technology of form & mould

making and pouring concrete into these,

shaping the concrete into sizes & shapesto build their complex networkof aqueducts, culverts, and tunnels.


3/41

AQUEDUCTSAQUEDUCTS

refinement of pozzolanas, a natural cement, found in the soil. cements, sand and gravels- the earliest invention of concrete. the idea to pour this mixture into molds for building precast blocks

marks the beginning of the idea for precast concrete.

3

To prevent them from stirring up trouble at home, the Roman armies were

often kept busy with engineering projects, . Concrete molds were filledlocally by the tens of thousands at construction sites


4/41

Different Forms of Precast Parts:Corner Pieces, Narrow, Short Or Long Blocks, Etc.The Individual Blocks May Have Looked Like Quarried Stone, But TheyWere The First Uses Of Precast Concrete

4


5/41

5

1905 Liverpool, England1905 Liverpool, England Pre-cast paneled buildings were

pioneered by England cityengineer -John AlexanderJohn Alexander BrodieBrodie

the first to develop and perfectthe idea of using precast

concrete forms in modernarchitectural design Genius also had him inventing the

football goal net. The tram stablesat Walton in Liverpool followed in1906. The idea was not taken upextensively in Britain. However, it

was adopted all over the world,particularly in EasternEurope and Scandinavia. John AlexanderJohn Alexander BrodieBrodie
http://www.mersey-gateway.org/server.php?show=conMediaFile.13734


6/41

6Transamerica Pyramid , San FranciscoThe Tallest Building To Use Precast Concrete


7/41


8/41

8BUNKERS & SILOSBUNKERS & SILOS


9/41

9BUNKERS & SILOSBUNKERS & SILOS


10/41

10RETAINING WALLSRETAINING WALLS


11/41

11CATCH BASINSCATCH BASINS


12/41

12BOX CULVERTSBOX CULVERTS


13/41

13UTILITY POLES & BASESUTILITY POLES & BASES


14/41

14SEPTIC TANKSSEPTIC TANKS


15/41

PRECAST CONCRETE SLAB TYPES:PRECAST CONCRETE SLAB TYPES:

1. (Solid) Flat slab2.Hollow Core slab3.Double Tee4.Single Tee

15


16/41

PRECAST SLAB TYPES:PRECAST SLAB TYPES:

1. (Solid) Flat slab Thicknesses of 0.10m, 0.15 and 0.20;

thinnest @ 0.07 m. Spans up to 25-0 / 7.62 m

Standard panel width = 4-0 or 1.20 m. when used on several continuous

spans having widths from 120 to 240

cm. with length up to 11 m2.Hollow Core slab Thicknesses of 0.10m, 0.15m,

0.20m,0.25m and 0.30m Spans up to 40-0 / 12.19 m Standard panel width = 4-0" / 1.2 mAs lightweight member made by extrusion in special machine Thickness ranges from 10 to 20 cm. Widths from 60 to 120 cm.As roof Spans augmented up to 9 m when 5

cm topping is applied to actmonolithically with the hollow planks.

16


17/41

17

(Solid) Flat slab

Hollow Core

Hollow Core

17


18/41

PRECAST SLABSPRECAST SLABS

3. Single TeeAs Roofing Spans up to more than

30m. Flanges of the tee T

constitute the floor or roofslab.

4.Double Tee most widely used sectionFor Longer Span Having

Depth Of 4.00 To 6.50 Mgenerally used on roofhaving a span up to 18 m

applied concrete toppingof at least 5 cm. actsmonolithically with theprecast members.

could be used on floors upto 15 m span dependingupon the load anddeflection requirements.

Roofs & Floors are made in wide variety of design to suit the different to suitconditions of span, magnitude of load, fire ratings and appearance.

Single Tee

Double Tee

18


19/41

PRECAST BEAMSPRECAST BEAMS((precast beam shapes depend upon the manner of framing)

19

1. Rectangular (RB) Typical beam width = 0.30 m and

0.40m Spans up to 50-0" / 15.240 m Typical designation = 16RB24 (16 =

width in inches, 24 = depth ininches)

Where the floor and roofmembers are supported on top ofthe beam

2. "L" and "IT" (inverted "Tee")beams (LB and IT)

Ledger beam designed to reduce the height of

the floor and roof construction. used to provide bearing Typically used to support slabs,

walls, masonry, and beams Typical beam width = 0.30m

Depths of 0.50m, 0.71m, 0.91m,1.1m, 1.32m, & 1,5m.

3. Single Tee" beams (ST) Combination beam and slab Spans up to 120-0" / 36. 58m Typical width = 8-0" / 2.4m Typical depths of 36" and 484. Double Tee" beams (DT) Combination beam and slab

Spans up to 100-0" / 30.48m Typical width = 8-0" / 2.4m Depths of 12", 18", 24" and 32"


20/41

PRECAST RECTANGULAR BEAMSPRECAST RECTANGULAR BEAMS 20


21/41

PRECAST L & IT BEAMSPRECAST L & IT BEAMS 21


22/41

PRECAST L BEAMSPRECAST L BEAMS 22


23/41

PRECAST Ledger & IT BEAMSPRECAST Ledger & IT BEAMS 23


24/41

24PRECAST ST BEAMSPRECAST ST BEAMS


25/41

25PRECAST DT BEAMSPRECAST DT BEAMS


26/41


27/41

27

PRECAST COLUMNPRECAST COLUMN

Axial Support Size ranges from 30 to 60

cm. Multi storey construction columns are made

continuous up to fourstories using corbels toprovide bearing for thebeam.

sometimes used directlyto support double teefloor members withoutthe use of immediatemember.


28/41

28

PRECAST COLUMNS

Dimensions SINGLE TIER WITH CORBELS DOUBLE TIER WITH CORBELS

Width (B): 300 ~ 900 at 50 mm increment 300 ~ 900 at 50 mm increment

Depth (H): 300 ~ 900 at 50 mm increment 300 ~ 900 at 50 mm increment

Height (L): 3.0 m ~14.0 m at 50 mm increment 6.0 m ~14.0 m at 50 mm increment


29/41

Wall PanelsWall Panels Standard widths: 8-0/ 2.4m Features: Flat or have architectural

features such as window and dooropenings, ribs, reveals, textures,sandwich (insulation built-in),sculptured, etc.

Designs: depending upon theArchitectural requirements.

Uses: as curtain walls attached tocolumns, beams or sometimes onbearing walls.

improve the thermal insulation of apanel, glass foam, glass fibers orexpanded plastic is inserted betweenthe two layers of interconnecting

lightweight concrete adequatelybonded to act as one unit. The stress on the precast unit made in

the in the factory is greater thanthose cast in place due to handlingand erection. Hence, control ofcracking is of great importance.

29


30/41

Wall Panel TypesWall Panel Types

1. Flat Panel2. Vertical Window or Mullion Panel3. Horizontal Window or Mullion Panel4. Ribbed Panel5. Double Tee Panel6. Spandrel

3.

1. 2. 4. 5.

6.

30


31/41

3131


32/41

MODERN DAY USESMODERN DAY USES

Concrete curtain walls Exterior cladding (may include

exposed aggregate) Structural walls Parts of mechanical systems

3-dimensional ability

ATTACHMENT METHODS:ATTACHMENT METHODS:1. Weld Plates

most common method ofattachment

use of steel weld plates. embedded plates in the

precast members are used aswelding surfaces for looseconnecting plates or angles

2. Rebar & Grout with slabs, reinforcing bars are

spliced into slabs and groutedin place

32


33/41

33

DOUBLE WALL PRECASTDOUBLE WALL PRECASTCONCRETE SANDWICH PANELSCONCRETE SANDWICH PANELS

Advantages Very rapid speed of erection Good quality control Entire building can be

precast - walls, floors, beams,etc.

Disadvantages

Very heavy members

Camber in beams and slabs

Very small margin for error

Connections may be difficult

Need bracing during on-site

erection of structure Somewhat limited building

design flexibility

Consists of two wythes of concreteseparated by an insulated void.

Thickness (commonly specified)-8 inches.

Connection: the two wythes of the

interior and exterior concrete layersare held together with steel

Height : up to a limit of 12 feet.a 9-foot clear height preferred for thequality of look and feel it affords abuilding trusses

Uses : multi-family, townhouses,condominiums, apartments, hotelsand motels, dormitories and schools,and single-family homes

Qualities: Speed of construction,durability of finished structure, andenergy-efficiency


34/41

34

FLOOR & ROOF SLAB SYSTEM REMOVABLE STEEL FORM PERMANENT CONCRETE FORM PREFAB SYSTEMS


35/41

35

CC--JOIST/PCF/R.C. SlabJOIST/PCF/R.C. Slab


36/41

36

PCF DimensionsPCF Dimensions


37/41

37

CC--JOIST on Steel IJOIST on Steel I--BeamBeam


38/41

38

CC--JOIST on Top of BeamJOIST on Top of Beam


39/41

39


40/41

40

PrePre--Cast Concrete FormsCast Concrete Forms


41/41

INSTALLATION GUIDE FOR CINSTALLATION GUIDE FOR C--JOIST/PCF SYSTEM:JOIST/PCF SYSTEM:

1. May be installed or placed manually or with the use of hoistingequipment.2. Laid on top of beams (concrete or steel I-beams) on its specified

spacing using a minimum of 4 seating clearance on concrete beamsand at least 3 bearing capacity for steel I-beams.

3. With joists set in its final spacing, PCF(s) are then placed on top of C-Joists shoulder in between distances, piece by piece from beam

interior face to end of span.4. Minimum 10 dowel bars spaced @ 0.30 m. to 0.60 m. o. c. with

about L/5 bend development length are required as shearconnectors.

5. 6mm slab temperature reinforcement @ 0.15 m. o. c. b. w., weldedwire fabric or equivalent. Temperature bars are placed d/2 of

specified slab thickness.6. 50 to 75 cm thick structural concrete slab with minimum compressivestrength of 3,000 psi @ 28 days taken from top line of C-Joist.

7. Shoring: NO shoring is needed for C-Joist 2.50 m. span and below.Mid-span shoring for spans above 2.50 m. to 5.00 m. and releasedONL after 7 days.

8. Standard installation of utilities as per conventional reinforced

t t

Pre-fabricated Concrete

Documents

Transcript of Pre-fabricated Concrete