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Assessment of structures

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All civil engineering structures are initially designed depending on certain design criteria, such as design loads, allowable stresses etc. But, damage due to an extreme event is always possible in a structure during its design life. Sometimes, undetected and un-repaired damage may lead to structural failure demanding costly repair and a huge loss of lives. Therefore, the problem of maintenance and repair of existing engineering structures involves damage detection at an early stage.

For massive structures like bridges, dams, flyover, ROB, RUB, chemical plants, thermal and nuclear plants, silos, pre heater towers, chimneys, etc., which were constructed some 20-40 years ago, it is necessary to test its functionality under the present load situation and quantify damage if any. Since it involves huge expenditure to demolish and reconstruct them, it is important to evaluate the residual life-RLA (residual life analysis) of these structures.

Performing NDT of concrete structures, which is a basis for the evaluation of RLA/remnant life analysis ??RLA studies. Many methods are traditionally used for flaw characterisation and measurement of residual stress. Combining these inputs many parameters, including mechanical properties, factor of safety in design, conservative operation of unit, inaccuracy in data extrapolation, overestimation of corrosion effects, etc., would be assessed.

Damage Detection and Condition Assessment of Civil Structures

In the assessment of existing structures, engineers are increasingly faced with not only the challenges of early detection of damage, but also the evaluation of structure performance and behavior under damage, and economical and efficient retrofitting of the damaged components commonly found in older structures. In order to maintain the safety and integrity of structures, research on the damage mechanism, assessment of structure performance in damaged status, and innovative technologies and materials to rehabilitate, repair, and retrofit structures are of great significance.

Retrofitting of a cement Plant Preheater Tower

Inspection by plant personnel revealed cracking in the concrete frame of a 326-ft-tall, 7-level preheater tower. Onsite plant engineers deemed the cracking significant, especially since the structure supports critical manufacturing process equipment. A structural engineering consulting firm was retained to evaluate the extent of the problem and formulate a repair plan on a fast-track basis. The firm mobilised at the site in less than 24 hours and performed an initial structural safety assessment. A comprehensive structural evaluation indicated that the structure required strengthening. Restoration consultants were engaged to assist locally with engineering and construction administration.

A specialty repair contractor also was engaged to review the constructability of several alternate repair schemes and maintain the fast-track schedule. After considering structural capacity and serviceability requirements, durability issues, the high-temperature operating environment, constructability, and an aggressive construction schedule, the team recommended a retrofit consisting of bonded post-tensioning within internal holes drilled in the beams. This solution was quite extraordinary, as it required precision-drilling horizontal holes up to 87 feet long in the beams of the elevated frame structure, without cutting existing embedded reinforcement.

Nondestructive impulse radar testing was used to locate existing embedded reinforcing steel, as well as to monitor the drilled holes’ trajectory. This process helped ensure proper hole alignment and prevent damage to embedded steel. The cored holes served as post-tensioning ducts. The repairs were executed on a fast track basis and under challenging circumstances, which included working high on the exposed structure through a cold winter with severe wind conditions. The unique retrofit resulted in a structure that is stronger, more serviceable, and more durable than the original tower. The project represented an exceptional team effort, and its success is attributable to the leadership of the owner and client, the ingenuity of the engineering team, and the resourcefulness of the contractor.

Case study authored by: Kolf, Peter R, Oesterle, Ralph G

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Concrete

Cement Makers’ Margins To Fall Rs 50-75 Per Tonne Amid West Asia Conflict

Crisil Sees Margins Easing Despite Steady Demand

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Crisil said operating margins of Indian cement manufacturers are expected to decline by Rs 50-75 per tonne (t) this fiscal to Rs 925-950 per t due to higher input costs triggered by the West Asia conflict. The analysis covered 18 cement companies accounting for nearly 90 per cent of India’s domestic cement capacity and noted margins had improved sharply to around Rs 1,000 per t in fiscal 2026.

Crisil noted that the reduction would be driven mainly by higher power and fuel costs, which account for about 30 per cent of total costs, as petcoke and imported coal prices have surged amid geopolitical uncertainties. Freight costs, which account for about a quarter of total costs, are also expected to remain elevated because of higher diesel prices. The impact on profitability is likely to be more pronounced in the first half of the fiscal year before easing commodity prices moderate cost pressures later.

The rating agency said steady domestic demand and strong balance sheets should keep credit profiles stable despite the moderation in margins. Green energy currently accounts for 35-40 per cent of the sector’s total electricity consumption and is expected to partly cushion higher energy costs. Operating cash flows are likely to remain resilient, supported by projected 6-7 per cent growth in cement demand this fiscal.

Crisil highlighted that demand growth will be driven primarily by infrastructure spending, which meets about one-third of sector consumption, and by a nearly 18 per cent higher budgetary allocation for core ministries that should support project execution. Weaker rural housing demand amid pressure on agricultural incomes from a possible below-average monsoon may be offset by improved urban housing demand supported by favourable home-loan rates and a strong pipeline of Pradhan Mantri Awas Yojana-Urban projects. Ongoing capacity additions will keep capital expenditure elevated and may lift net debt to EBITDA to between 1.2 and 1.4 times from around 1.0 time last fiscal, though ratios are expected to remain healthy.

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Concrete

UltraTech Board Approves Rs 50 bn Fundraise Via NCDs

Company to issue half a million debentures for expansion plan

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UltraTech Cement’s board of directors has approved raising Rs 5,000 crore (Rs 50 bn) through non?convertible debentures issued in rupees.

The finance committee cleared a proposal to issue up to 500,000 fully paid, unsecured, listed, rated, redeemable, rupee?denominated, non?convertible, non?cumulative debentures of Rs 1 lakh each (Rs 0.1 mn each), aggregating to the Rs 5,000 crore programme.

As of June 2026 the firm reported net debt of Rs 15,875 crore (Rs 158.75 bn) and said its capacity expansion projects under execution are backed by capital expenditure of about Rs 17,000 crore (Rs 170 bn) over the next two to two?and?a?half years.

UltraTech spent Rs 9,500 crore (Rs 95 bn) on capital expenditure in financial year 2026 and in April the group crossed 200.1 mn tonnes per annum of domestic grey cement capacity and 205.5 mn tonnes per annum of global capacity.

The chief financial officer indicated the company would take consolidated capacity beyond 242 mn tonnes per annum, with grey cement capacity reaching 212.7 mn tonnes per annum by the end of financial year 2027. He noted the net debt?to?earnings before interest, taxes, depreciation and amortisation ratio stood at 0.87 times as of June 2026 and the company was confident of ending financial year 2027 with the ratio below one time.

In the first quarter of financial year 2026?27 UltraTech’s net profit attributable to owners rose 16.8 per cent year?on?year to Rs 2,599.3 crore (Rs 25.993 bn) and revenue from operations increased 15.9 per cent to Rs 24,648.20 crore (Rs 246.482 bn). The board approval is expected to complement internal cash flows as the company advances its expansion programme.

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Concrete

Lokesh Lays Stone For Rs 31 Billion Cement Unit In Kadapa

Line-2 expansion to make Kadapa a major cement hub

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Andhra Pradesh Education and IT Minister Nara Lokesh on Wednesday laid the foundation stone for the Line-2 expansion of Dalmia Bharat Cement at Chinnakomerla village in Mylavaram Mandal in Kadapa district. The project carries an investment of Rs 31 billion (bn) and is slated for completion by the third quarter of the financial year 2028. The expansion is intended to boost industrial growth and employment generation across the Rayalaseema region.

Once commissioned, the Kadapa facility will become Dalmia Bharat’s largest integrated cement manufacturing ecosystem in southern India, creating over 1,000 direct and indirect jobs and opening new business avenues for regional micro, small and medium enterprises and transport operators. Lokesh said the expansion signalled growing corporate confidence in the state and reflected the practical ease of doing business that secured repeat investment.

He placed the project within the government’s wider economic targets and recalled the Yuvagalam padayatra commitment to generate two million (mn) jobs within five years, noting that the state would cultivate talent while industry created opportunities. Lokesh highlighted Andhra Pradesh’s competitive pursuit of major manufacturing accounts, mentioning past successes and a personal initiative to engage global investors when persuading them to anchor expansion in the state.

The plant will leverage Kadapa’s abundant limestone reserves to scale production and sustainability. Clinker capacity is planned to rise from two point five million tonnes per annum (mn tpa) to six point one mn tpa, while overall cement output will increase from three point six mn tpa to nine point six mn tpa. The unit is designed to operate on over eighty per cent renewable energy and deploy waste heat recovery, zero liquid discharge, water recycling and advanced AI systems to optimise efficiency. Industries Minister TG Bharat, BC Welfare Minister S. Savitha and Jammalamadugu MLA C. Adinarayana Reddy attended the ceremony.

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