Concrete

Optimisation of Concrete Cost for Metro Projects

Published

8 years ago

June 30, 2018

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An attempt is made to develop a systematic approach for estimating the quantity of concrete and optimisation of concrete cost based on a case study. The article will be published in two parts. The present article (Part 1) discusses about the Metro Projects in brief, construction methodology adopted, estimation of concrete quantity and associated cost. The next article (Part 2) will be discussing about the methodologies used for optimising the cost associated with production, transportation and placement of concrete.

In India, for infrastructure projects, the concrete is used as one of the essential construction materials. Appropriate selection of concrete (type/grade) and precise estimation of concrete quantity are essential to achieve optimised cost of concrete. Further, optimisation of construction cost related to concrete could also be achieved by appropriate selection of construction methodology along with equipment selection (rental/purchase/outsourcing) suitable for site conditions. various equipment are required for the production, transportation and placing of concrete. The selection and usage of these equipment are crucial for the successful completion of project work. Generally, the selected equipment shall fulfill project requirements within the timeframe.

In this regard, comprehensive analysis on selection of equipment and their usage in construction site needs to be carried out by the contractor well in advance (i.e bidding stage). If equipment planned to use in construction site is inadequate, it will be difficult to follow the schedule of fast track infrastructure project. On the other hand, to reduce the time period of construction, the plan for excess usage of equipment, may not be financially beneficial for the project. Hence, there is need to develop a systematic method for for optimising the cost of concreting by accurate estimation of concrete quantity and effective decision on selection of appropriate construction systems. The method was developed based on a case study (construction of metro project in Mumbai).

Mumbai Metro project
The master plan for metro project in Mumbai includes nine corridors covering a length of 172 km, out of which 32.50 km is proposed underground and the rest is elevated. First 11.40 km long elevated metro corridor between Versova – Andheri – Ghatkopar (Line 1) is commissioned in June 2014. Elevated corridors between Andheri (East) to Dahisar (East) – 16.475 km (Line 7), Dahisar to DN Nagar – 18.589 km (Line 2A) and underground metro between Colaba – Bandra – SEEPZ is under construction. Construction of elevated corridor between DN Nagar to Mandale (Line 2B) is about to start. After implementation of the Mumbai metro master plan, 70 lakh commuters are expected to get benefit, in turn, will reduce the traffic on roads and congestion in suburban rails.
1.1. The metro line 2A is selected as a case study for the present article. Brief scope of elevated metro project is as follows:

Viaduct: Design and construction of around 18 km elevated viaduct including viaduct and ramp for depot entry.

Stations: Design of 16 elevated stations (excluding architectural finishing and pre-engineered steel roof

structure).

Construction methodology: Construction methodology of a metro project is explained in this section. Civil construction activities includes mainly two pases, i.e., construction along the alignment and construction of precast elements at casting yard.

Construction along the alignment (route of metro line): Key construction activities along the alignment are as follows:

Barricading is provided to enclose the construction area to ensure safety and coordinated movement of vehicular and pedestrian traffic (Fig. 1).

Pile locations are accurately marked on ground by using the total station. Pilot trenches are made to check for any infringing underground utilities. If utilities are found, they are shifted for hassle free construction. To initiate the piling work, hydraulic rotary piling rig is positioned at piling location for boring of the pile (Fig. 2). While boring, temporary casing is provided up to required depth depending on the ground strata. After completion of boring, reinforcement cage is lowered. For casting of pile, the tremie pipe is lowered and concrete is poured up to required level through the tremie pipe.

After completion of group of piles for one pier, excavation of the pile cap is taken up. After laying PCC, the reinforcement cage is tied and concreting of pile cap is done.

After tying reinforcement for pier, the starter is cast. After casting the starter, balance formwork is erected for casting pier. Concrete will be placed up to bottom of pier cap using the truck mounted boom placer (Fig. 3 and Fig. 4). At the end, anti-crash barrier is cast.

Precast pier cap from casting yard is transported to the site and erected on pier by using the crane (Fig. 5 and Fig. 6).

"Stitch concrete" (Fig. 7) of pier cap (junction of pier reinforcement and pier cap reinforcement) is done by using the crane and bucket.

First stage stressing of pier cap is done. Bearing pedestals are cast using crane and bucket. For curing of bearing pedestals, curing compound can be used.

Precast "U" girder from the casting yard is transported to the site using multi-axle hydraulic trailer. The girder is placed on bearing pedestal using high capacity cranes (Fig. 8).

After erection of girders in the adjoining spans, second stage stressing of pier cap is done.

Construction of station building by combination of precast and cast in-situ concrete is done at each station location (Fig. 9).
Casting yard: Casting yard is mainly utilised for casting of the precast elements (pier caps, "U" girder, "I" girders, etc.), which are transported to the desired location along alignment for erection. Key construction activities at the casting yard are as follows:

Development of infrastructure at casting yard is very important activity. This includes the RMC plant installation, stacking of materials for RMC plant, construction of casting beds for precast piers, "U: girders and "I" girders, arrangement for stressing activity at each casting bed, stacking beds for casted precast elements and shed / gantry for handling formwork and casted precast elements (Fig. 10 and Fig. 11).

For casting of "U" girders, first cleaned bottom and outside shutters are placed in positioned and aligned properly. Thereafter, the reinforcement cage is placed in position. Inside shutters are placed after placing reinforcement and high tensile steel wires. Stressing of strands is done before casting "U" girders (Fig. 12 and Fig. 13).

Concreting of girder is done by using the placer boom. After achieving desired concrete strength, girders are shifted on the stacking beds (Fig. 14).

Casting of precast pier cap is done at the casting beds of pier cap. Truck mounted boom placer is used for placing concrete. After achieving desired concrete strength, piercaps are shifted on stacking beds (Fig. 15 and Fig. 16).
Estimation of concrete quantity
Based on the project, the required concrete quantity for viaduct and station needs to be calculated.. The estimated concrete quantity forms the base for calculating the cost of concrete and associated optimisation. Total concrete quantity at a glance for the selected project.

The cost associated with the concrete production and placement shall be estimated based on the following categories. Materials cost – depends on various grades of the concrete and the required quantity in each grade.

Plant and machineries cost – depends on the duration of project and the total concrete quantity required.

Transportation cost – depends on the location wise concrete requirement (at casting yard and/or along alignment).

Placement of concrete cost – Based on the site requirement, the concrete placement method (pumping/placer boom/bucket) needs to be planned for various concrete structures.

Details about planning and costing of above points are explained in subsequent points.

Costing of concrete

Concrete using fly ash/ground granulated blast furnace slag (GGBS) along with 53 Grade Ordinary Portland Cement (OPC) has been considered in calculation of cost.

Following are the possible technical advantages of using fly ash/GGBS along with OPC :

Diameter of viaduct pier is 1.8 m. In case of usage of only OPC, the core temperature of concrete may be higher and there are chances of thermal gradient leading to cracks within mass of concrete piers. Usage of fly ash will reduce the heat evolution during hydration, leading to reduced core temperature.

If high grade concrete is produced using only OPC, cement content in concrete increases. This may lead to shrinkage of concrete. Use of fly ash may minimise the shrinkage cracks.

In case of use of fly ash/GGBS, there will be secondary hydration which will make concrete more impermeable and greatly improve the durability of concrete structure.

Cohesive concrete can be achieved. Further, surface finish of the concrete structure can be improved.

For piles and pile caps, concrete can be produced using 53 grade OPC and GGBS.

For mass concrete, up to 70 per cent GGBS of total cementitious materials can also be used. This will be helpful in reducing core temperature of concrete. However, the limits on the percentage replacement shall be specified in the case of pumping.

Average material cost (as received from ready-mix concrete suppliers in Mumbai) for different grades of concrete required in metro construction using OPC and fly ash is given in Table 1. The fly ash is used up to 30 per cent (by mass) in concrete and the percentage replacement varies depending on the grades of concrete.

In case of GGBS usage, there will be further reduction of material cost in the range of Rs 200 to 400 per m3, depending on the grade of concrete and percentage of GGBS used.
Summary
The present article discussed about the metro projects in brief along with construction methodology of an elevated viaduct. Further, the article discussed about the method of estimation of concrete quantity and associated costs for various grades of concrete.
Acknowledgment

Mumbai metro rail projects

Schwing Stetter (India) for information on equipment required for RMC plant

AIMIL Ltd. for providing information on laboratory equipment

RMC suppliers in Mumbai for providing rates of RMC and raw materials
Authors

Mahesh Tendulkar
M.Tech Student
Construction Technology and Management
Department of Civil Engineering
Indian Institute of Technology Bombay
Powai, Mumbai – 400 076.
tendulkar_mahesh@yahoo.com
Basavaraj M B
Chief Engineer (Civil) – Metro
Mumbai Metropolitan Region Development Authority
Old Administrative Building, 6th Floor
Bandra – Kurla Complex, Bandra (East)
Mumbai – 400 051.
basavaraj.mb@mailmmrda.maharashtra.gov.in
Prakash Nanthagopalan
Assistant Professor
Construction Technology and Management
Department of Civil Engineering
Indian Institute of Technology Bombay
Powai, Mumbai – 400 076.
prakashn@civil.iitb.ac.in

Table 1 :Material cost for various grades of concrete

Concrete	Material cost/m3 (in Rs)
M15	3,800
M35	4,550
M40	4,650
M45	5,200
M55	5,600

Concrete

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

Crisil Sees Margins Easing Despite Steady Demand

Published

2 hours ago

July 29, 2026

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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.

Concrete

UltraTech Board Approves Rs 50 bn Fundraise Via NCDs

Company to issue half a million debentures for expansion plan

Published

1 day ago

July 28, 2026

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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.

Concrete

Lokesh Lays Stone For Rs 31 Billion Cement Unit In Kadapa

Line-2 expansion to make Kadapa a major cement hub

Published

1 week ago

July 20, 2026

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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.