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

Assam Cabinet Approves Rs. 110 bn JK Lakshmi Cement Investment

ADB-backed project to restore 102 community beels also approved

Published

11 hours ago

September 28, 2026

admin

The Assam Cabinet has approved an investment of Rs. 110 bn by JK Lakshmi Cement for a clinker manufacturing unit and four associated cement grinding units in the state. Chief Minister Himanta Biswa Sarma announced the decision on 24 September 2026, along with approvals covering wetland restoration and industrial support.

The proposed cement investment is expected to generate around 2,000 direct jobs. The project forms part of the state government’s latest measures to attract manufacturing activity and strengthen industrial infrastructure. The Cabinet also approved a State Capital Investment Subsidy for eligible manufacturing units covered by the substantive provisions of the Uttar Poorva Transformative Industrialization Scheme, or UNNATI, 2024.

The subsidy will apply to units that qualified under the scheme but were unable to secure registration by the extended deadline of 30 September 2026. The measure is intended to support eligible businesses that missed the registration process while continuing to meet the scheme’s substantive requirements.

The Cabinet also cleared an Asian Development Bank (ADB)-funded project for the restoration and rehabilitation of at least 102 derelict community beels across Assam. The ADB loan component is Rs. 6.38 bn, while the Assam government’s contribution will be Rs. 1.59 bn.

In another decision, the Cabinet approved a rent-based or pro bono arrangement for constructing a laboratory and ancillary infrastructure for the Spices Board under the Ministry of Commerce and Industry. The facility will be built at Ulubari in Guwahati, with the Agriculture Department coordinating with the Public Works Department (Buildings) to construct it according to designs and specifications provided by the board.

Concrete

JSW Cement Receives Rs. 2.3 bn GST Demand Notice

JSW Cement faces a GST demand over alleged incorrect classification.

Published

11 hours ago

September 28, 2026

admin

JSW Cement has received a show-cause notice proposing a Goods and Services Tax (GST) demand of Rs. 2.3 bn, along with applicable interest and a 10 per cent penalty, over an alleged incorrect classification of transactions. The notice was issued by the Additional Commissioner of Central Tax, Belagavi Audit Commissionerate, on September 24, 2026.

The proposed demand relates to the period from April 2022 to March 2024 and has been issued under Section 73 of the Central Goods and Services Tax (CGST) Act, 2017. The company disclosed the notice in a filing with the stock exchanges and said the matter involved an alleged short payment of GST.

The proposed amount comprises Integrated GST (IGST) of Rs. 1.22 bn, Central GST (CGST) of Rs. 540.5 mn and State GST (SGST) of Rs. 540.5 mn. The department has also cited alleged contraventions of Sections 9, 37 and 39 of the CGST Act, with interest proposed under Section 50 and the penalty under Section 73.

JSW Cement said the financial impact of the notice would be limited to the proposed tax demand, applicable interest and penalty. However, it assessed that the matter would not have a material impact on the company. The cement manufacturer is preparing its reply to the show-cause notice.

The notice was issued to JSW Cement, which is part of the Sajjan Jindal-promoted JSW Group. The company reiterated that the total proposed GST demand stood at Rs. 2.3 bn, excluding the applicable interest and 10 per cent penalty, and that the proceedings remained at the show-cause stage.

Shares of JSW Cement ended at Rs. 115.65 on the BSE on Thursday, down Rs. 2.60, or 2.20 per cent, from the previous close. The stock movement came as the company disclosed the proposed tax demand and its intention to respond to the department’s notice.

Concrete

Montra Electric, Wonder Cement Deploy 250-Vehicle EV Fleet

Fleet to haul cement on a 1,450-km corridor across four states

Published

11 hours ago

September 28, 2026

admin

Montra Electric and Wonder Cement have begun commercial operation of a 250-vehicle deployment of Rhino 5538 EV 4×2 tractor-trailers on an electric freight corridor linking Rajasthan with ports in Gujarat. The companies said the fleet is being used for regular cement logistics rather than a limited pilot, making it one of the largest heavy-duty electric truck deployments by an Indian industrial company.

An initial 30 trucks were introduced from Wonder Cement’s plant in Nimbahera, Rajasthan, in July 2026. They are hauling full payloads on daily routes between Nimbahera and Dahej Port and between Nimbahera and Tuna Port, covering approximately 1,450 km across Rajasthan, Madhya Pradesh, Maharashtra and Gujarat. The vehicles operate to schedules comparable with those of the company’s conventional diesel fleet.

The corridor is supported by 13 dedicated charging stations positioned to enable long-distance duty cycles within industrial turnaround times. The Rhino 5538 EV is available with a 55 t Gross Combination Weight option and is designed for cement, coal and clinker transport. Its specifications include a 282 kWh lithium iron phosphate battery, a Permanent Magnet Synchronous Motor producing 280 kW and 2,000 Nm of torque, 18 per cent continuous gradeability and a 6-speed Automated Manual Transmission.

The vehicle has a stated range of 198 km under specified test conditions, with one side loaded and the other empty. It can charge from 20 to 100 per cent State of Charge in 60 minutes and is supported by more than 95 per cent assured uptime. Montra Electric and Wonder Cement said the deployment would assess electrification through payload capacity, turnaround performance and daily availability in live freight operations.

Montra Electric said the same operating model could support steel, mining, infrastructure and port haulage, where fixed routes and predictable turnaround windows are common. The company has more than 750 heavy-duty electric vehicles on Indian roads and has covered over 30 mn km across its deployments. Montra Electric operates as the clean mobility arm of the Murugappa Group, with businesses spanning heavy commercial vehicles, smaller commercial vehicles, three-wheelers and electric tractors.