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Quality Control Laboratory Equipments – Maintenance and Calibration

Various kinds of equipments used in qulity control laboratories for civil construction projects find mention in an earlier post in this blog. In this post maintenance and calibration of these equipments have been briefly discussed. Proper maintenance and periodic calibration of laboratory equipments is a very important aspect of the entire QC system itself for … Continue reading

Slipform Construction of High-rise Building Cores (Part-III)

Contd. from Part-II ….. Highly skilled supervision is necessary for slipform construction of highrise building cores or any other tall structure for that matter. The slipform unit is carefully designed and once accepted, no change should be made in it during construction unless well-examined and approved by the designer. If a crane too is tied … Continue reading

Slipform Construction of High-rise Building Cores (Part-II)

Contd. from Part-I ….. This entire unit consisting of the slip-forms, cross-beams, platforms etc. are raised in synchronisation along the jack rods by means of hydraulic jacks of suitable capacities. The jack rods, which are usually embedded in the concrete walls of the core itself, can be either sacrificed or removed later on if so … Continue reading

Slipform Construction of High-rise Building Cores (Part-I)

This post provides a quick overview about construction of service cores of tall buildings using slipform construction technique. Slipform construction technique has been gaining a lot of popularity over the years in the construction of mid to high-rise buildings because of the many advantages it has to offer, especially for buildings having about ten storeys … Continue reading

Post Tensioning (Part-II)

Contd. from Part-I …. The main equipments used in post tensioning operationing are: a) Stressing Equipmemts: These include jack & pump of suitable capacities. Proper calibration certificates for these equipments are quite necessary. For general idea, calibration tolerances for these max be +/- 2%. Calibrations are checked periodically in order to ensure accuracy throughout. Scrutiny … Continue reading

Post Tensioning (Part-I)

Post tensioning is an useful method of reducing size or increasing load bearing capacities of concrete structural elements like bridge decks, girders and suchlike. Unlike pre-stressing, where stresses are applied to steel well before pouring concrete, in case of post-tensioning the same are applied only after concrete attains sufficient strength. Like pre-stressing, Post tensioning too … Continue reading

Grouts & Grouting (Part-IV)

Contd. from Part-III …. Some ready-to-use grouts prescribe mixing of small sized stone chips for certain cases, usually for larger gaps, in order to induce additional strength apart from reduction of cost. Normally, good quality stone chips of sizes varying from 6mm to 10mm are suitable for the purpose. However, grout manufacturer’s specifications usually provide … Continue reading

Grouts & grouting (Part-III)

Contd. from Part-II…. Pre-packed, ready-to-use grouts have many advantages over ordinary grouts prepared in-situ with OPC. One need not worry about procuring ingradients or mix proportion etc. as everything come ready in bags and it just needs to be mixed with water or the prescribed fluid as per manufacturer’s literature. These grouts are readily available … Continue reading

Grouts & grouting (Part-II)

Contd. from Part-I…. For mixing purpose, revolving type, tilting mixer of suitable capacity may be used. For preparing small quantity of grout, large mixer drum is not suitable as proper mixing won’t take place. Mixing needs to be done for a minimum period of 3 minutes & mixing location should be as near as possible … Continue reading