How to build safe structures: Letters to The Editor

How to build safe structures

Good design/engineering alone can't make a robust building. A building is a product of planning, structural design, detailed drawing, construction materials, workmanship, curing process and close supervision during construction. As we know, the weakest link of a chain is the strength of the chain. As such to achieve the desired strength of a building, all steps and procedures from design to completion must be followed in letter and spirit. Attempt to bypass any procedure/process would weaken the strength of the building as a whole.

A brief description of proper construction activities are as under: A geotechnical investigation is done to ascertain the bearing capacity of the plot, where any construction is planned. After completion of the design of a building (say), by an individual, it should go to other experts as well to check and review its correctness. If it is found ok, then it should go to the approver for approval. Wrong calculations or interpretation in design, if any, can easily be found out during these multi-tier checking. The same is the case with drawing preparation. Second, procurement of materials and testing: materials like steel, cement, sand, brick and stone chips etc should be procured as per the quality specified in IS-code. Further, construction materials should be sent to NABL (National Accreditation Board for testing and calibration Laboratory) to ensure their strength and usability before put to use. Third, execution: detailed checking of reinforcement placement and its lapping cover before casting of slab, beams, foundations, columns, piles etc. The shuttering and staging arrangements have to be checked properly for strength, proper size and water tightness. After completion of checking only by a competent engineer, agencies should be allowed to go ahead with casting. For each batch of the concrete mixture used, two sets of cube moulds, which are filled with a concrete mixture for testing, one set to be tested after 7 days and the second set to be tested after 28 days from casting for verifying the compressive strength of the concrete. The cast structures are to put under the curing (watering) process after 14 hours from casting. This process has to continue for 10 days. For slab/flat surfaces: the curing process has to continue for 28 days. For Pile foundations: generally, three types of testing are carried out. Vertical load test, pull out the test and lateral test. Quality assurance and control is a painstaking and costly affair. Therefore, close monitoring is needed in every step in construction. Buildings constructed adhering to all norms and procedures would produce safe structures. Thus, it is the prime responsibility of development authorities of town/city to monitor construction activities including checking of design calculations of buildings, conducting stage wise inspection at all critical stages of the structure by competent technical personnel in the true spirit, if not done so far.

Prafulla Dowarah,

Guwahati.

Hypocrisy

Congress leaders are often heard in various news channel debates addressing Yogi Adityanath as Rajeev Bisht. Of course, Rajeev Bisht is the former name of Uttar Pradesh Chief Minister Yogi Adityanath and he disclosed it in his affidavit filed during the nomination form to the ECI. Uttar Pradesh Chief Minister was born Rajeev Bisht and later on, his name got changed after he embraced saynashi. He was born Hindu by religion and Indian by nationality. When Congress workers address him in his former name he raises no issue then why the same Congressmen object and protest when someone addresses president Sonia Gandhi as Antonio Marino, which her original name is given by her Italian parents when she was born as an Italian. It is nothing but hypocrisy.

Julie Bhuyan,

Gaurisagar.

Discard plastic, use a paper bag

On World Environment Day the Union Environment Minister renewed the pledge that India would be single-use plastic (SUP) free nation by 2022. The State government had already banned the use of plastic bag more than one and a half years back from October 2019. The need of the hour now is to strictly enforce the existing ban on single-use plastic in the State. The banned plastic (below 40-micron thickness) for single-use is non-biodegradable and being not absorbable in the soil causes physical damage to soil health. Woefully, the scattered empty plastic materials on the roads find their way into the drains and due to frequent showers during the prolonged rainy season, the overflowed clogged drains inundate roads and by-lanes that constrains the commuters besides polluting the surroundings. Alternative to SUP has to be found in introducing paper bags and earthen cups, tumblers etc.

Pannalal Dey,

Guwahati.

Ban diesel-driven cars

It refers to regular increase on daily basis in prices of petrol and diesel. Procurement-prices of petrol, diesel and kerosene are almost the same. However, kerosene is sold at highly subsidized prices because it is mainly used by the poor. Diesel was priced lower than petrol because diesel is mainly used in transportation. But now prices of diesel are regularly increasing thus resulting in the rising price of goods. The motto should be to keep diesel prices in control by allowing its use mainly for commercial transportation and not at all in the use of cars.

It is not proper that even super costly cars used by the elite rich are nowadays having diesel engines. This is a misuse of the policy of keeping the price of diesel lower than petrol. The production of diesel-driven cars should be altogether banned. It will also help reducing pollution because diesel causes more pollution than petrol. It is noteworthy that in Delhi, diesel cars are allowed to be used for ten years while petrol cars are allowed to be used for fifteen years. Ban on the production of diesel cars will enable the Central government to restrict the price-rise of diesel which in turn will keep prices of public transportation and goods under control.

Subhash Chandra Agrawal,

Delhi.