Building Materials & Construction CE-2153

Timber-as Building materials

Nur-160518

Raihan-160521

Biswazid-160526

Hasan-160529

Asha-160530

Group No. 04Group Members

Forestry & Wood Technology Discipline, Khulna University, Khulna, Bangladesh

TIMBER

The wood which is suitable or fit for engineering construction or engineering purpose is called Timber

Timber is one of the primary materials of engineering construction from the very earlier time

Only from Exogenous trees, we get timber

Sources of Timber

Advantage of timberCan be easily handled and joinedTimber can be used for both load –bearing structure and non load bearing instrumentIt can easily converted to any shape and sizeThe wastage in timber construction is lessTimber has better insulating properties than other materialsDurability of timber can be very high if properly seasoned and preserveTimber construction is light in weight and strong and can be made economicalFor aesthetic & decorated appearance Easily available High energy efficiency

Characteristics of good timbersStrong, stiff, tough & durableFree from natural & artificial defectRadially sawnColor should be dark as it indicate strong & durable timberStructure should be uniformHave a good workability Density should be highHave a sweet smellshould have elasticity Should be resistant to compression Should be fire resist Should have law water permeability

Sawing of Tree LogMethods of Sawing:Ordinary or Plain sawing Radial or Rift sawingTangential sawingQuarter sawing

Seasoning • Fresh timber have about 30 to 40 percent of

sap or moisture. This moisture is very harmful for the life of timber

• It is essential to remove the sap by applying certain special methods• All such are collectively termed as seasoning

Seasoning

Water

ArtificialNatural

Kiln chemical Electric

Seasoning technique

Advantages of SeasoningIt has reduced weight Strong & durable

Resistance to decay and rot Take high polish

Easier to work with Last longer

Defects in Timber

Defect due to seasoning

Some other defects occurring in timber:

Defects due to conservation

Defects due to fungiDefects due to Insects Knots

Objects of timber preservationTo increase the life of timber structures

To make the timber structures durable

To protect the timber from the attack of destroying agents such as fungi, insects, etc.

Timber preservatives

The main timber preservatives are : Ascu treatment Coal tar Paint Cresote oil Chemical salts Zinc chloride is the most extensively used of this types.It is clean and odourless

Uses of timber• Building construction• House post construction• Construction of bridge and boat• Furniture & instrument • Railway slipper • Toys and engraving work• Formwork of cement concrete

Use of timber in construction• Beam• Trusses • Rafters• Doors frame and shutters• Windows frame and shutters• Stair cases• Poles• Piles• Columns

Common timber in Bangladesh

TeakGarjanGamariJarulShissoShirisMahoganyChapalish etc.

Summary From all of these slides, we have learned….

• Source of timber• Advantages of timber• Characteristics of good timber• Sawing methods of Log• Seasoning & seasoning technique • Defects of Timber• Preservation of timber• Use of timber• Use of Timber in construction • Common timber of Bangladesh

That’s all…..

Thank you