Wednesday, June 16, 2010

construction technology


Excavation and Timbering of trenches

1. Sketch the following

i. Typical timbering in firm soil (Depth up to 1000mm)

ii. Typical timbering in loose wet soil (Depth up to 1000mm)

2. Write down 20 or more technical terms used in connection with excavation work and timbering of trenches.

3. Write down10 or more tools and machineries used in connection with excavation work and timbering of trenches

4. What are the safety precautions which should be used in connection with excavation work and timbering of trenches

Typical Timbering In Firm Soil Up To 1000mm

When earth has been excavated to a considerable depth the vertical faces of the excavations need supporting by means of timber, to prevent the soil from falling in and injuring the workmen or the work upon which they are engaged.

The strength of the timbering used for this purpose necessarily depends upon the nature of the soil, the depth of the excavations, and the length of time it is likely to be kept open.

The struts should not be closer together than 6 feet, otherwise they will prove a considerable inconvenience to the workmen in the trenches.


Typical Timbering In Loose Wet Soil Up To 1000mm

Should the looseness of the soil necessitate supports being fixed at closer intervals than 6 feet the system of timbering shown in Fig. 02 should be used. In this case it will be noted that the poling boards are supported by long horizontal members about 6 by 4 inches, called Wailings or Wailing Pieces, which in turn are supported by struts at intervals of 6 feet.

If the trenches are deep the timbering is inserted in tiers until the required depth is reached, the struts being placed vertically under one another, and at a distance of about 6 feet apart, so that stages may be supported upon them for the disposition of the excavated soil - 6 feet being the limit of depth from which an excavator can comfortably throw soil out of a trench.

Timbering To Excavations 122

Technical Terms Used In Connection With Excavation And Timbering Of

Trenches

Cohesive soil Hard soil Firm soil

Moderately soil Loose soil Loose and water logged

Iron shoe Puncheons Folding wedges

Uprooting Struts Sole plate

Ron strap Polling board Lacing boards

Dead load Vertical sheeting Planks

Non cohesive soil Peat

Live load Excavation

Tools And Machinery Used in Connection With Excavation Work.

Plumb rule Excavator Crow bar Level

Wheel barrow Mamoty Wacker Compactor

Case Dozers Wheel Loaders Bobcat Skid Steer Loaders

Safety Precautions Which Should Be Adapted In Excavation And Timbering Of Trenches

Ø Provide timbering or other supports where necessary

Ø Men erecting supports should be in a protected position

Ø When should only work within the supported section and should be prohibited from entering unsupported sections.

Ø Notices should be posted to this effect.

Ø Men should not walk or clamber about on the timbering as this weakness it.

Ø Don’t place the excavated spoil or other materials or plant close to edges of excavations.

Ø Do not allow plant to move close to the edges of excavations

Ø Creaks in timbering can indicate a danger or collaps.

Ø The sides of large, open excavations should be bettered or adequately supported where soil conditions require it and when men have to work in close proximity to the face.

Module number B.M. 123

Foundations

1. Sketch the following and name the parts

i. Strip foundation using Random Rubble masonry

ii. Strip foundation using brick masonry

iii. Strip foundation using R.C.C. Base

iv. Pad foundation

2. Write down 20 or more technical terms used in connection with foundation work

3. i. Ground Materials may consist of five groups. Name them with examples

ii. Name four types of foundations

Strip Foundation Using Random Rubble Mesonry

C:\Documents and Settings\Dilan\Desktop\RANDOM1.gif

Strip Foundation Using Brick Masonry

C:\Documents and Settings\Dilan\Desktop\image108.jpg

Strip Foundation Using RCC Base C:\Documents and Settings\Dilan\Desktop\fig-b-3.gif

Pad Foundation

C:\Documents and Settings\Dilan\Desktop\structural-03.jpg

Terms used in connection with foundation work

Rocks Cohesive Non cohesive Peat Made up ground

Gneiss Sand Granite Sandstone Limestone

Slope Bearing capacity Retaining wall Wetland Raft foundation

Bore holes Stratum Excavation Ramming Strip foundation Trial pits Laterite Pad foundation Cut and fill Pile foundation

Gravel Reinforcement

A broad classifications of the ground material may consist of five groups.

Ø Rocks

Ø Cohesive

Ø Non-cohesive

Ø Peat

Ø Made up ground

Rocks: These includes gneiss, granite, sandstone, limestone and laterite.

Cohesive Soils: The main cohesive soil is clay.

Non Cohesive soil: These include gravel and Sand.

Peat: Peat is black or dark in colour and very often smelly.

Made up ground or fill: These are low lying areas and depression are sometimes filled with various materials such as house refuse, industrial refuse, industrial refuse, building debris, excess earth from other sites, etc.

Types Of Foundations

1. Strip foundations

2. Pad foundations

3. Raft foundations

4. Pile foundations

Module number B.M. 124

Walls

1. Sketch the following

i. Alternate plan (two courses) of a right angle quoin (90° corner) of a 9" thick brick wall in English bond

ii. Alternate plan of a right angle Tee junction of a 9" thick brick wall in English bond

iii. Alternate plan of a right angle stopped end of a 9" thick brick wall in English bond

2.

i. Sketch the following

Elevation and cross section of a Random Rubble wall, 7΄-0" high from ground level (coursed or uncoursed) and name the parts.

ii. Name five types of rubble walls and give their advantages

3. Write down the terms, machineries and tools used in connection with the construction of walls.

Alternates Plans (two cources) Of A Right Angle Qoin (900 corners) Of A

9” Thick Brick Wall In English Bond

C:\Documents and Settings\Dilan\Desktop\EnglishBond.png

Alternates Plans (two courses) Of A Tee Junction Of A

9” Thick Brick Wall In English Bond

Alternates Plans (two cources) Of A Stop End Of A

9” Thick Brick Wall In English Bond

Elevation And Cross Section Of A Random Rubble Wall

C:\Documents and Settings\Dilan\Desktop\Fig-211-Random-Rubble-setDry.jpg

Random Rubble Masonry (Uncoursed)

The stones are used as they are received from the quarry. The stones are not in same height. They are levelled at every 300 to 500mm. height. Stone chips and spalls are used to fill the empty spaces. The joints are about 12mm. Though stones are used to full width of the wall if the width of the wall is less tha 600 mm, for width more than 600mm 2 stones of lap joint is used. This masonry is useed for the construction of godowns, labour quarters, compound walls.

Suitability: Used for construction of walls of low height in case of ordinary buildings.

http://www.ustudy.in/sites/default/files/rubble%20masonry.jpg

Random Rubble Built To Courses

The random rubble masonry in which stones are laid in layers of equal height is called random rubble masonry. In this masonry, the stones are laid in somewhat level courses. Headers of one coursed height are placed at certain intervals. The stones are hammer dressed.
Suitability: Used for construction of residential buildings, go downs, boundary walls etc.

C:\Documents and Settings\Dilan\Desktop\Fig-209-Random-Rubble-built-up-to-Courses.jpg

Squared Rubble Uncoursed

Un coursed square rubble masonry: The squared rubble in masonry which hammer dressed stones are laid without making courses is called un coursed square rubble masonry. It consists of stones which are squared on all joints and beds by hammer dressing. All the stones to be laid are of different sizes.

Suitability: Used for construction of ordinary buildings in hilly areas where a good variety of stones are cheaply available.

C:\Documents and Settings\Dilan\Desktop\Fig-133-Uncoursed-Rubble.jpg

Squared Rubble Built To Coursed

Coursed Square rubble masonry: The square rubble masonry in which chisel dressed stones laid in courses is called coarse square rubble masonry. This is a superior variety of rubble masonry. It consists of stones, which are squared on all joints and laid in courses. The stones are to be laid in courses of equal layers. and the joints should also be uniform.

Suitability: Used for construction of public buildings, hospitals, schools, markets, modern residential buildings etc and in hilly areas where good quality of stone is easily available.

C:\Documents and Settings\Dilan\Desktop\Random-Rubble-Built-In-Courses-10093.jpg

Ashlar masonry

The stone masonry in which finely dressed stones are laid in cement or lime mortar is known as ashlars masonry. In this masonry are the courses are of uniform height, all the joints are regular, thin and have uniform thickness. This type of masonry is much costly as it requires dressing of stones.

Suitability: This masonry is used for heavy structures, architectural buildings, high piers and abutments of bridges.

C:\Documents and Settings\Dilan\Desktop\ashlar-masonry-001.jpg

Terms Or More Used In Connection With The Building Of Walls

External wall Internal wall Solid wall Frame wall

Load bearing wall Non Load bearing wall Arris Bed

Header Stretcher Face Frog or Kick

Bed joints Course Quoin Perpends

Racking back Tooting Bat Closer

Bull nose Splay Dogleg

Tools And Machinery With The Building Of Walls

Spall hammer Mallet Iron hammer Scabbing hammer

Line and pins Plumb rule & bob Square Trowel Drag

Spirit Level Pick-axe Crow bar Pitching tool

Gauge Punch Chisel Nicke

Point Jumper Hand saw Wedge & Feather

Level Frame saw Cross-cut saw

Module number B.M. 125

Doors & Windows

1. Sketch the following and name the parts

i. Ledged, braced and battened door

ii. A framed and paneled door

iii. A paneled and glazed doo

2. Sketch a typical timber window with three slashes including slats on top and name them

3. List out 20 or more terms used in connection with the construction and fixing of doors and windows.

Ledged Braced And Battened Door

C:\Documents and Settings\Dilan\Desktop\building-a-shed-door1.jpg

Framed And Paneled Door

C:\Documents and Settings\Dilan\Desktop\drawing1_lrg.jpg Paneled And Glazed Door

C:\Documents and Settings\Dilan\Desktop\Door-glossary.gif

Typical Timber Window

C:\Documents and Settings\Dilan\Desktop\wp243e6f7f_0f.jpg

Technical Terms Used In Doors And Window

Door Rail Sill Mullion

Post Head Horns Door frame

Spur stone Door slashes Wrought iron traps Wrought iron dowel

Flush doors Nose Hanging edge Edge lipping

Bottom rails Glazed panels Intermediate rails Slide Hung

Module number B.M. 126

Stairs

1. Sketch the plan and cross section of a R.C.C. stair case and name the parts. Also give the proposed dimensions.

2. What are the types of stairs? Select two out of them and show them with sketches.

3. List out 20 or more terms used in connection with the construction of stairs.

Types Of Stairs

Basically there are three types of stares.

1. A strait flight stair

2. A quarter turn stair

3. A half turn stair

A strait flight stair rises from floor to floor in one direction with or without an intermediate landing, hence the name straight flight.

C:\Documents and Settings\Dilan\Desktop\stair-seting-out.gif

A quarter turn stair rises to a landing between two floors, turn through 900 then rises to the floor above, hence “Quarter turn”.

C:\Documents and Settings\Dilan\Desktop\bespoke-staircases-qt.gif

Cross Section Of A RCC Stair Case

C:\Documents and Settings\Dilan\Desktop\staircase-section.jpg

Plan Of A RCC Stair Case

C:\Documents and Settings\Dilan\Desktop\2ndflrfullsize.jpg

Technical terms used in construction of stairs

Landing Rise Tread Nosing Hand rail

Yield steel Flight Steps Pitch Head room

Doe leg Balustrade Half turn Quarter turn Cast stone

Stair well Mild steel Rails Steep Stair Going

Thread Shallow stairs

Module number B.M. 127-A

Wall and floor finishes

1. What are the common types of plastering used in building works? Including the following details.

- Materials used

- Proportions

- Thickness & finish

2. What are the types of floor finishes and their advantages?

3. Write down 20 or more technical terms used in connection with the work in carrying out wall and floor finishes.

Common types of plastering used in building

Description

Material

Proportion

Thickness

Finish

External Plastering

Cement: Lime: Sand:

1:1:5

5/8"

Rough/Semi rough

Internal Plastering

Lime: Sand

1:5

1:2

1/2", 5/8"

Finished smooth with lime putty.

Cement: Lime: Sand:

1:1:5

5/8"

Finished smooth with lime putty.

Soffit plastering

Cement: Sand

1:2 , 1:3

3/8"

Finished smooth with lime putty.

Plinth plastering

Cement: Sand

1:2 , 1:3

1/2", 3/4"

Finished smooth with cement putty.

Cement rendering

Cement: Sand

1:2

1/2", 3/4"

Finished smooth with cement putty.

Skirting

Cement: Sand

1:2

1/2", 5/8"

Finished smooth with cement putty.

Types Of Floor Finishes

Ø Brick paved and cement rendered

Ø Concrete paving and cement rendered

Ø Asphalt

Ø Pressed tiles

Ø Glazed tiles

Ø Clay tiles

Ø Granite

Ø Terrazzo

Ø Rubber tiles

Ø Parquet flooring

Technical Terms Used In Connection With The Floor And Wall Finishes

Exterior wall Interior wall Lime plaster Cement plaster

Salt carbon Scaffolding Gauges Mortar

Smooth finish Coping Damp proof course Soffit

Parapet top Skirting Curling Moldings

Brick paved Concrete paved Rough finish Proportions

Cement, lime, sand plaster

Module number B.M. 127-B

Painting

1. List out the various stages of painting in respect of the following new surfaces.

- Wood/Timber

- Iron/Steel

- Concrete/plastered surfaces

2. Names 20 or more types of paints commonly used in building works and their advantages.

3. Write down 20 or more technical terms used in connection with painting work.

4.

Wood/Timber

Ø Applying sand and paper to the surface along the grain

Ø Clean the surface with a dry brush or piece of rag

Ø Apply two coats of Aluminum primer

Ø Fill the cavities, cracks, etc with stopping

Ø Apply first coat of paint (Under coat)

Ø Apply second coat of paint (Finishing coat)

Iron/Steel

Ø If there is rust, removing them with chopping, scrapping or wire brushing

Ø Clean the surface. If there is oil or grease on the surface, wipe this off with clean rag and paint thinner

Ø As soon as finished the cleaning apply a coat of primer

Ø Apply first coat of paint (Under coat)

Ø Apply second coat of paint (Finishing coat)

Iron/Steel

Ø Brush down to remove the dust, loose sand and efflorescence and scrape off any splashes of plaster mortar or cement

Ø Stop up cracks and holes with plaster or one of the patent fillers mixed with water

Ø Then if a primer is needed apply a one coat of Alkali Resisting Primer

Ø Apply first coat of paint (Under coat)

Ø Apply second coat of paint (Finishing coat)

Types Of Paints Commonly Used On Building

Enamel paints Snocem

Weather shield paints Whitewash

Emulsion paints Samara wash

Anticorrosion paints Wood primer

Distemper Anti-corrosive

Cement paints Filler

Gloss paints Luminous Paint

Filler Aluminous filler

Bituminous paints Water paints

Elastic paints Varnishes

Technical Terms Used In Connection With The Work In Carrying Out Painting

Corrosion Wear Decay Alkali resisting primer Efflorescence Adherent Entrained pain skins Distemper

Bituminous conspicuous Blemishes Tackiness

Wrinkling Fat edges Blistering Peeling

Obscure Brushing Spraying Dipping

Absorbent surfaces Porous glass paper Sand paper

Grain Knots Rust Rag

Putty Discoloration Scale Crystals

Shrink Elastic paints