Testing Building Material Onsite.

 Testing Building Material Onsite

By: Sahil Kishore Sharma


The major concern on site execution is the quality of the material received and with the inflating prices of the material checking the quality becomes a major challenge for the construction industry. In large projects a dedicated quality team is  incharge for maintaining the overall quality of the materials but in low cost projects especially in tough terrains like J&K the accessibility of the experts is also a very hard task. With this article the fundamental theme is to touch upon the points which can be used as guiding principles for a low cost project so that if the expert is not accessible at least if basics are followed a fairly decent construction can be executed in India. Field tests of brick, cement, sand and stone chips are very much essential as they are the most common construction materials which are used in almost all of the civil engineering construction from brickwork to floor finishing . As a civil engineer, working in a site is the challenging one, as on the site engineer all the responsibility and liabilities depend upon for good quality construction.  But alone a good supervision is not enough for a good construction having required properties and durability. A proper quality control is essential at all the stages, specially at the very start , where we have to select the right materials for a type of construction, as the materials are the cells of each structure. 




For Bricks:

The following field tests are to be performed in order to determine if a Brick is good :-

  1. A good brick should be of proper shape and standard specified size, the edges of it should be sharp, there should not be any cracks and fissures on the brick. 

  2. The colour of a good brick should be copper red in colour. A yellowish tint on brick indicates that it is under burnt and hence possesses lower strength, and if a brick is of dark blackish blue colour then it indicates the brick is over burnt and is brittle in nature. 

  3. When a brick is struck by a hammer or against another brick, it should emit a clear metallic ringing sound, it should not be dull. 

  4. A freshly fractured brick should show a homogeneous compact structure without any lumps. 

  5. If a brick is dropped from about a height of 1m on a hard ground or on another brick, it should not break.When a brick is scratched with fingernail it should not leave any impression on the brick. 

  6. A good brick (1st Class) should not absorb water by not more than 20% of its own Dry weight when immersed in water for a period of 24 Hours.

For Cement:

  1. The cement should be of Greenish Gray colour for Ordinary Portland Cement, and Blackish Gray colour for Portland Pozzolana Cement and Whitish Gray colour for Portland Slag Cement.

  2.  There should not be any hard lumps on cement, the cement should be finely powdered. If cement contains hard lumps, then it must be rejected. 

  3. The cement when rubbed between fingers should feel smooth, it should not feel granular. If it is granular then it means adulteration with sand. 

  4. A cement paste should feel sticky in between fingers. 

  5. When a hand is dipped into a heap or into a bag of cement, it should feel cool, not warm. 

  6. If a handful of cement is thrown into a bucket of water, the cement should sink, not float as the Specific Gravity of Cement is greater than that of Water. 

  7. If a thick cement paste made on a glass and immersed in water should set, not crack.

For Sand:

  1. The Sand should be free from organic impurities and mineral salts, The maximum permissible quantity of organic impurities should be restricted to 5%. 

  2. The Sand should be of Golden Yellow colour. 

  3. The Sand particles should be sharp and angular to increase the interlocking property between the sand particles. 

  4. The sand should coarse for Concreting and medium sand may be allowed in brickwork and is preferable for plastering works.

For Stone Chips ( Coarse Aggregate):

The visual tests or field tests for Coarse aggregate, that is stone chips are very limited though there are many laboratory tests available. Mainly the following things are observed as for Field Test :-

  1. The Stone Chips are to be well graded to increase the mechanical interlocking between them. 

  2. Stone Chips should be Angular as far as possible and be porous. 

  3. The Stone Chips should not be flaky and elongated. 

  4. The Stone Chips should not contain organic and other impurities, as only 5% clay content in concrete can reduce the strength of the concrete as much as 20%.

This onsite checklist is very important in order to reduce the chances of errors in the quality of the materials. If these quality check lists are fair and the product is as per standard a the improvement in the construction is significant. People in doubt should also approach experts and if not accessible people should also look for alternate options like online consultation and E-monitoring.

 

For any kind of Construction Consultancy Kindly visit Sahrajengineering.com


* This is a research article only for educational purpose, Images are for reference.

 

Comments

Post a Comment

Popular posts from this blog

Shipping Container Houses

Image
Shipping Container Houses  By: Sahil Sharma Pic Courtsey Vector Stock What Is a Shipping Container Home? A shipping container home is a structure which are made up   from steel shipping containers—large reusable intermodal containers that are used for the  transport of goods. The various sizes in which standard shipping containers are available are: 20 feet by 8 feet or 40 feet x 8 feet: The 20-foot containers are 160 square feet, while the 40-foot shipping containers offer 320 square feet of living space.  These containers can be used as a standalone home or personal office, or you can combine multiple containers to create a multilevel residence. Shipping container structures, like small houses, RVs, or silo homes, are gaining popularity as potential homeowners seek out alternative building solutions for the traditional multi-bedroom house. Mobile, versatile and potentially carbon neutral, shipping containers are finding their footings as the starting point for new ...
Read more
Image
 LOW COST HOUSING TECHNLOGIES IN INDIA  By : Sahil Kishore Sharma  The government of India has given a recent push  to promote low-cost housing in India and has  set a  target to build 2 Crore affordable houses by March 2022, this segment of affordable housing has seen huge demand and sales recently.  One in every five houses is now priced at less than INR 25 lakh. Affordable housing contribution in the residential sector has seen an increase from 8% to 21% within a short span of three years.  Figure: Segmentation of housing prices in FY16 and FY19 Growing urbanization  has led to migration towards cities and resulted in an increased demand for affordable low-cost  housing . Moreover, with sustainability gaining momentum, there is a need to balance both energy consumption and the environmental impact of materials used for building houses. Low-cost building materials not only increase access to permanent housing for people from low and m...
Read more