BS 6093-2006 pdf free download

BS 6093-2006 pdf free download.Design of joints and jointing in building construction Guide.
Some materials respond to changes in moisture content following changes in weather conditions, and appropriate allowance has to be made taking Into account the environment at time time of CoflStflietion. Examples of such materials are concrete blockwork and timber.
Care should be taken about the moisture content of absorbent materials in storage and during the course of construction, in order to minimize Subsequent EnoVenWilt.
In such envirorunents as are found In swimming pools and certain industrial processes where high humidity occurs, the behaviour of moisture-sensitive materials should he given special consideration.
4.6.2.2 Irreversible inherent deviations
Irreversible inherent deviations are due to non-cyclic factors. They occur over pre(lictable short or long-term periods depending on the nature of the material.
In addition to reversible movement, concrete is subject to irreversible drying shrinkage and thermal contraction.
PLastic shrinkage can occur during the first few hours after placing through the loss of water from the plastic concrete by evaporation or, sometimes, by absorption into adjacent materials. Plastic shrinkage is common in hot weather and in drying winds and can result in cracking. It can largely he avoide(l by slowing down the drying of the concrete. Early thermal contraction can be significant in concrete over about 0.5 m thickness. It is clue to the natural cooling that takes place when the heat of hydration passes Its peak. The temperature rise can typically be about 20 K, two days after placing. The designer should he aware of the effect of early thermal contraction and, where appropriate, should provide joints or planes of weakness to confine cracking to predetermined positions.
Drying shrinkage is a long-term process and can continue over many months. Any movement is influenced by the size of section, the concrete mix, (he uuount of reinforcement an(l the environment. Allowance should he made for the effects of drying shrinkage when detailing concrete hlockwork. (‘alcium silicate bricks need to he protected against excessive moisture up to and during construction. Provision should be made for the free circulation of air within the stack so that the bricks may dry out before they are built in.BS 6093-2006 pdf free download.