Concrete

Making Concrete in Cold Conditions

Published

10 years ago

February 28, 2017

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Cold weather is defined as a period when the average daily temperature falls below 4?C for more than three successive days. These conditions warrant special precautions when placing, finishing, curing and protecting concrete.

Concrete production always faces a problem during cold weather. There are two main problems associated with cold weather. The general rule is that the concrete has to gain strength till about 500 psi (35 kg per cm2).

Concrete can freeze before it gains strength which breaks up the matrix;
Concrete sets more slowly when it is cold – very slow below 6? C; below 4? C, the hydration reaction basically stops and the concrete doesn’t gain strength.
But these are concrete temperatures, not air temperatures. So when it’s cold, the concrete has to be protected until it can handle the cold on its own. The general rule is that the concrete has to gain strength till about 500 psi (35 kg per cm2). Almost the same time that the concrete achieves 500 psi compressive strength, hydration of the cement consumes enough of the water in the original mix so that even if it does freeze, there’s not enough water left in the pores to damage the concrete. With most concrete, even at 6?C, this happens during the second day.

To help it reach that 500 psi strength, the mix can then be changed to get it to set more quickly or protect the concrete from the cold – or more likely do both.

Changes to Concrete Mix during Cold Weather
Many of the problems with cold weather can be overcome by the ready mix producer. Here are a few things to keep in mind:
Hot water: A ready mixed concrete producer will usually have, and use, hot water in the concrete when the weather turns cold. Most producers will try to have the concrete be at least 180C when it leaves the plant, which is generally good enough depending on air temperature and thickness of the concrete element. The slump has to be specified at less than 100 mm and air-entrained concrete should be used to reduce bleeding.

Accelerators: Since colder weather leads to colder concrete, the set time can be delayed. Accelerators added to the concrete can keep it on schedule. Addition of 2 per cent (by weight of cement) of calcium chloride is the traditional way to accelerate the hydration reaction – it is very effective and reasonably cheap. But – a big but -that much chloride can lead to corrosion of any steel embedded in the concrete (like rebar) and can lead to a mottled surface appearance with coloured concrete.

Non-chloride accelerators are also widely available and are very effective. They won’t discolour the concrete, but they are a bit expensive. Accelerators are not anti-freeze agents – they simply increase the rate of the hydration reaction.

Fly ash: Producers should typically stay away from using fly ash or slag cement in cold weather, since those materials set more slowly and generate less internal heat; slag can cause the same effect.

To make the reaction a bit hotter, the ready mix producer can add some extra cement (typically 60 kg per cubic metre) or can use Type III (high-early strength) cement, which hydrates more rapidly.

Producers have to be careful with water reducers in cold weather, since they can slow the set time. Besides, cooler concrete seldom needs water reduction since the cooler temperatures prevent slump loss. For admixtures added at the job site, they shouldn’t be used if they have frozen. The chemicals may have separated.

Precautions before Placing Concrete in the Cold
When cold weather comes on unexpectedly, the following tips will help:
Frozen ground: Concrete should be never placed on frozen ground or onto ice or snow. There are a couple of problems with this. First, frozen ground will settle when it thaws, cracking the concrete. Second, when the ground is cold, the concrete in contact with it will be cold and will set more slowly. Crusting might also occur, with the top part of the concrete set and the bottom still soft. If the ground is frozen, it can be thawed using hydronic heat pipes and blankets (such as those from ground heaters), or electric blankets.

Anything that will come in contact with the concrete should be warmed up, including forms and any embedment, to at least 00C. If it’s not too cold and everything is covered with tarps the day before the pour, it will stay dry and warm enough.

Concrete

Dhanekula Institute Signs MoU with Adani Cement

Agreement to expand internships, industrial visits and practical learning

Published

5 hours ago

November 5, 2026

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The Department of Civil Engineering at Dhanekula Institute of Engineering & Technology, Ganguru, organised an industrial interaction programme under the Adani FutureX Programme on Thursday. The programme focused on strengthening engagement between the institute and the cement industry while giving students greater exposure to professional practices.

Yedukondalu, technical head for Andhra Pradesh and Telangana at Adani Cement, delivered a technical lecture on concrete as a man-made material. The session covered the importance of concrete in construction, its properties and applications, and its significance in modern infrastructure development.

The lecture also addressed the role of quality cement and suitable concrete technology in supporting durable and sustainable construction. The discussion connected classroom learning with the technical considerations involved in infrastructure projects and construction practices.

A key part of the programme was the signing of a memorandum of understanding (MoU) between the Department of Civil Engineering and Adani Cement under the Adani FutureX Partnership Agreement. The agreement is intended to strengthen industry-academia collaboration through opportunities for student internships and industrial visits.

The initiative is expected to provide students with practical exposure, improve their understanding of industrial practices and help bridge the gap between theoretical knowledge and real-world applications. Dhanekula Institute Chairman Dhanekula Ravindranath Tagore, Secretary Dhanekula Venkata Bhavani Prasad and Director DKRK Ravi Prasad supported the initiative, with the institute leadership highlighting the importance of industry-institution interaction in enhancing students’ technical employability.

Concrete

JK Lakshmi Cement Begins Rs. 110 bn Assam Plant Project

Project Kamakshi will produce 2.5 mn t of cement annually by FY2029.

Published

5 hours ago

November 5, 2026

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JK Lakshmi Cement has laid the foundation stone for Project Kamakshi, its first integrated cement manufacturing facility in Assam, marking the company’s entry into Northeast India. The groundbreaking ceremony took place at Umrangso village in Dima Hasao district in the presence of Assam Chief Minister Himanta Biswa Sarma.

The project involves an investment of Rs. 110 bn, including the mining lease. It will have annual cement production capacity of 2.5 mn t and a 1 mn t clinkerisation unit, with completion scheduled for FY2029.

The facility is expected to create more than 2,000 jobs and will primarily serve the growing Northeast market. It will also include dedicated railway sidings for transporting raw materials and finished cement, supporting supply chain reliability and regional distribution.

Chairperson and Managing Director Vinita Singhania said the project represented the beginning of a long-term relationship with Assam and the wider Northeast. She said the plant would help provide locally produced cement, employment and dependable supplies as the region’s infrastructure development accelerated, while enabling the company to grow alongside the communities it serves.

The investment supports JK Lakshmi Cement’s strategy of expanding into high-growth markets beyond its established presence in Northern, Western and Eastern India. The company expects the project to contribute to regional economic development and infrastructure growth while pursuing its long-term objective of achieving net-zero emissions by 2047.

Concrete

Kshatriya Engineering College Signs MoU with Adani Cement

Agreement to provide students with industrial exposure and training

Published

5 hours ago

November 5, 2026

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The civil engineering department of Kshatriya Engineering College in Nizamabad has signed a memorandum of understanding (MoU) with Adani Cement to provide students with industry-oriented training and practical exposure. The agreement is intended to connect classroom learning with workplace requirements in the construction sector.

Under the partnership, students will receive opportunities to take part in industrial visits and internships. The arrangement will also include guest lectures by industry experts and guidance on live projects, allowing students to gain first-hand understanding of industry practices and emerging construction technologies.

College secretary and correspondent Aljapur Devender said the initiative was designed to bridge the gap between academic instruction and industry expectations. He said the collaboration would help students develop practical skills and improve their employment prospects after completing their studies.

Principal Dr Katakam Srinivas said exposure to industrial practices was important for civil engineering students and would complement their academic learning. He said the MoU would support the development of their technical knowledge and confidence through greater familiarity with professional work environments.

Administrative officer B. Narender said the collaboration would familiarise students with modern construction technologies, quality standards and project management practices. Civil engineering department head N. Deepika said the agreement would help students understand recent developments in the construction sector and prepare for professional careers. The college said the partnership would give learners a broader view of the processes and standards followed in the industry, while helping them relate their academic studies to practical project requirements.