A global leader for engineered solutions and innovative products that enables safer, faster, stronger, and more sustainable construction, Leviat is part of CRH, the largest global building materials company in the world and is connected to a global network of about 73,000 construction industry experts. Sachet Pawar, National Specification Manager, Leviat spoke about the global rebar coupler market, its market size in India, key market trends, opportunities, drivers, issues, the significance of often-overlooked components like rebar couplers in an era of high-rises, compliance with industry norms, workmanship and quality measures, application in airports, subways, bridges and tunnels and application of couplers for construction efficiency and safety, among others. Excerpts:The global rebar coupler market is expected to reach over US$800.0 million by 2025. What is the market size in India and how would you rate this segment for opportunities and drivers?The market share in India is relatively low as compared to global usage but with recent steps taken from the Bureau of Indian Standards (BIS) for compulsory usage of couplers for 20 mm rebar and above, it is going to increase tremendously. Infrastructure projects play a major contribution in the usage of couplers, which are popular for reducing steel consumption. The opportunity is enormous as there are lots of projects such as Metro, high speed rail, highways and nuclear plants, etc. Key drivers for couplers are ease of monitoring and efficiency of couplers as per standards laid down by the BIS, convenience in getting testing done and last but not the least, the cost as compared to the conventional lapping process of rebars. Coupler usage seems easy and convenient, but if the proper methodology for threading on rebar or designing of couplers with proper engagement of threading with rebar is not done properly, it can affect the integrity of the structure. How has your company fared in the last few years? As a CRH company, Leviat in India believes in quality, which is also one of its core principles. We work with customers who share a similar thought process. The share of wallet in terms of wide product portfolio sales from projects has increased with customers whom we are associated with, be it in the public or private sector.What is the significance of revising IS 16172:2023 code for couplers?Leviat in India has played a significant role in revising the coupler codes, collaborating closely with the Bureau of Indian Standards (BIS) on IS 16172:2023, to elevate performance standards.A few examples are:A) In IS 16172:2014, static tensile strength criteria of samples tested in the laboratory was limited to 600 Mpa strength where the rebar was Fe500 maximum. Now, we have rebars with yield strength of 550, 550D and 600 Mpa so it is 30 percent greater than the yield of the respective grade of rebar. So if the rebar is of 55D the performance should be 550x1.3 = 715 Mpa. Therefore, the results are more realistic and accuracy can be achieved in terms of performance of couplers, irrespective of the grade of rebar.B) Tall buildings were not defined in 2014 but post the release of National Building Code in 2016, now in IS 16172:2023 version, the couplers that qualify for high cycle fatigue criteria are mandatory for tall buildings.Please shed light on the significance of often-overlooked components like rebar couplers in an era of towering high-rise structures.The Indian construction industry is still working in a conventional manner. Often products like couplers are treated like a commodity item. The Leviat technical team has taken charge to educate the construction community on rebar couplers and their importance. Using couplers comes with the responsibility of threading on rebars as well, which is challenging at sites, especially in Metro cities like Mumbai with space limitations, which could be a reason for couplers being overlooked. How does the company stay compliant with the latest industry regulations and policies?We follow stringent quality control measures even before production of couplers begins i.e. with the raw material we test if it complies with mechanical and chemical properties. Also, India is among the core panel that drafted the IS 16172:2023 code. The overall intention was to elevate quality standards of couplers and threading service, which are being done in a haphazard manner. In couplers, we meet all the ‘type’ test requirements as per IS 16172:2023, in service we use standard SOPs for threading on rebars and gauges to maintain onsite quality of threading.What quality measures are involved in threading of rebars?Threading on rebar is a very important aspect while using couplers. A coupler supplier should be liable not only for the coupler, but also for the quality of threads that are being done on site. As per SOPs, the four steps that need to be followed for parallel threading on rebar are cutting, cold forging, threading and proof loading and each step is interconnected with the preceding one. For e.g.: If we eliminate the cutting process, the uneven rebar surface may lead to improper forging and improper threads will be created on therebar. Post threading, the threads will look fine but if the go and no-go gauges are not used to check the tolerance in threads, it may end up losing the coupler while tightening it at the site.How will acceptance test criteria increase the usage of couplers?Acceptance test comes after the ‘type’ test criteria are fulfilled. Once the coupler qualifies the type-H criteria i.e., the high cycle fatigue requirement as per IS 16172:2023, it qualifies a vendor but the ‘acceptance test’ of rebar has to meet sampling criteria of IS16172:2023, which emphasises on consistent performance of couplers and ensures confidence regarding their usage.What are other application areas since standard or tapered thread rebar couplers could be mainly used in high-rises, airports, subways, bridges and tunnels?We should not limit coupler usage for specific applications. Couplers are a replacement for lapping on rebar so they can be used for both vertical as well as horizontal applications. Vertical applications are lapping in column, pile, walls, etc, and horizontal applications are for rafts, beams and diaphragm wall dowels, etc.Can you share a success story where the application of couplers, as per IS 16172:2023 resulted in notable improvements in construction efficiency or safety?One notable success story involves application of couplers as per IS 16172:2023 in 2 significant construction projects in Mumbai: a residential and commercial project with precast construction of 55 floors and a residential project for the Military Engineering Service using in-situ construction methods. In the 55-floor precast construction project, the use of couplers enhanced construction efficiency. The primary advantage was the reduction in rebar congestion, which facilitated easier and quicker assembly of precast elements. This streamlined workflow resulted in faster project completion times and ultimately saving costs. For the Military Engineering Service project, the robust connection provided by the couplers enhanced structural performance of the building, ensuring it met stringent safety standards. The use of couplers minimised the need for on-site welding and lapping, reducing potential safety hazards and ensuring a safer working environment for the team.
