Concrete for Modern Infrastructure Projects
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Concrete for Modern Infrastructure Projects S.K.Gupta, Dir/Projects th 28 May 2018 CONTENTS • Project Overview • Project Route • Geology • Quality Assurance • Concrete Specifications • Design Mix • Quality Control/Workmanship/Certification and Control • Construction Monitoring • Challenges/risk PROJECT OVERVIEW PROJECT OVERVIEW Contract Packages – Civil Works Package Length Stations Limits No. (K.M.) Cut & Cover NATM Cuffe Parade, Vidhan Bhavan, Hutatma Chowk 1 Cuffe Parade to CST 4.20 Churchgate C.S.T. Kalbadevi, Girgaoan, 2 CST to Mumbai Central 4.05 Grant Road Mumbai Central, Mahalakshami, Science Museum, Acharya Atre 3 Mumbai Central to Worli 5.06 - Chowk, Worli Siddhi Vinayak, Dadar Shitaladevi 4 Worli to Dharavi 6.08 Dharavi, B.K.C., VidyaNagari Santacruz 5 Dharavi to Santacruz 4.94 CSIA Domestic, Sahar Road, Santacruz to CSIA 6 4.45 CSIA International Airport - (International) CSIA (International) to MIDC, SEEPZ Marol Naka 7 4.16 SEEPZ Total Length of the Corridor 33.5 PROJECT ROUTE PROJECT ROUTE Fully Underground • Length: 33.5 Km • Stations: 27 (26 U/G + 1) • Completion Cost: US$ 3.7Billion • Phase 1: SEEPZ to BKC- June 2021 Phase 2: BKC to Cuffe Parade- Dec 2021 2021 2031 Ridership 1.22 Million 1.70 Million Headway 4 min, 16sec 2 min, 55 sec (CP-BKC) 256 sec 175 sec Coaches 248 (31 x 8 336 (42 x 8 cars) cars) MUMBAI METRO LINE – 3 GEOLOGY TOWARDS SEEPZ PAREL MAZGAON B.K.C. LITTLE COLABA GIRGAON CUFFE PARADE DADAR MUMBAI CHURCHGATE CENTRAL MAHIM WORLI BOMBAY COLABA RECLAIMED LAND Mumbai Geology, Historical Background MML – 3 GEOLOGY, MUMBAI Anticipated Construction Challenges Geological Possible Construction Issues Condition Compact Basalt High degree of jointing, water bearing strata, rock fall, instability Contact Boundary Filling of clay at contact plane, weak rock mass at between Basalt and contact zone Breccia Tuff, Breccia Clay minerals in rocks produce sticky muck and may jam cutters affecting progress Intertrappean Shale Unstable due to their inherent softness which may be aggravated by their closely spaced laminations, water seepage along bedding planes, rock fall due to softening in contact with water, swelling behaviour MML – 3 GEOLOGY, MUMBAI Varying Geological Conditions Ground Water Table 18.6 m STATION Shale, Breccia, Basalt Grade IV, V Basalt Grade I, II TUNNEL QUALITY ASSURANCE Quality Assurance General Quality Assurance of MML3 is implemented on a well structured state-of-art system, monitored and recorded • Mainstays for assuring quality: • Contract Documents • ISO, BIS,DIN, EN • Project Quality Plan • Design Quality Plan • Manufacturer Quality Plan • Design and Drawings • Method Statements • Instruments used for ensuring quality: • Routine Audits & Construction Monitoring • Approval Process • Assessment Process • Request for Inspection (RFIs) • Contractor’s Surveillance Inspections • Non Conformance Report (NCRs) • Corrective Action Report (CARs) Quality Assurance Materials Testing • 25 dedicated Site Laboratories which are approved and in par with NABL requirements • Testing witnessed by Mumbai Metro Rail Corporation and General Consultant, results evaluated for acceptance and well documented . Sand . Aggregate . Cement . Water . Concrete Samples . Steel Random or specific testings done through National Accreditation Board for Testing and Calibration Laboratories (NABL) accredited and renowned third party laboratories Quality Assurance Batching Plants Concrete production is carried out in 17 approved dedicated Batching Plants across packages and Depot, which are on par with international standards • Mix Design Control - Automated • Delivery Records - Automated • Quality Management System implemented • Plant Laboratory & Quality Control Department • Truck Washing Arrangement • Production and Quality Control monitored by Mumbai Metro Rail Corporation and General Consultant, evaluated for acceptance and well documented Quality Assurance Casting Yard Seven Casting Yard across packages, which are on par with International Standard • Moulds with inbuilt Vibrators • Controlled Shed for protection of Concrete casting • Equipped with Electric overhead travelling (EOT) Cranes, Tilting Machines etc. for segment handling • Stacking Yard for storage • Batching Plant with site laboratories CONCRETE SPECIFICATIONS Concrete for Mumbai Metro Line 3 • The consumption of Concrete in the project is about – Tunnels :4,00,000 m³ – Station Structure :16,00,000 m³ • Specifications calls for Design Life of 120 years. Concrete Specifications • Concrete Structural requirements are minimum M35 grade and minimum M45 when in contact with corrosive water • Durability performance test at 28 days for water permeability according to DIN 1048 and Rapid Chloride ion penetration according to ASTM C-1202 • Drying Shrinkage and Moisture Movement Tests according to BS 1881 • Minimising risks by limiting – Chloride, Sulphate and Alkali content within concrete • All Concrete constituent materials shall be conforming to relevant Structure Standards/Codes Underground Underground • Admixtures supplied by reputed brands and close monitoring done on it’s formulation and dozing. • Daily adjustment on Aggregates and Moisture Content Project Requirements for Concrete • Structural requirements . For Tunnel Lining Segment Concrete M45 - M50 . For Station Concrete M40 – M60 • Durability . Water Cement Ratio maximum 0.4 . Water Permeability less than 10mm . Rapid Chloride Penetration less than 1000 coulombs . Use of Fly Ash limited to max 25% of cementitious content . Range of cementitious content not to exceed 500 Kg/m3 MML3 Durability Criteria DESIGN MIX Concrete Design Mix Approach – MML3 Durability is assured by good quality and well placed concrete with limited cracks and hence no need for coating the rebar or stainless steel. Objective Strategy “Defining concrete design mix through Way to Achieve” Durability” • Limit water content • Minimising construction cracks and • Limit sand fraction volumetric distortion • Combining cementitious materials to • Minimising path of transportation achieve low heat mechanism in concrete mix matrix • Optimise the mortar fraction • Effective casting in plastic state • Evaluation of trial works in deciding • Durability compliance with specification design mix Design Mix - Precast Concrete for Tunnel Lining Segment Mix Design: M50 Grade Typ. Tunnel Segments Water / Cementitious 0.33 Constituent Materials Kg / m3 Cement OPC 53 380 Fly Ash Type F 100 Ultrafine 20 Manuf. Sand - Basalt 778 CA 10mm - Basalt 416 CA 20mm - Basalt 575 Water 145 Admix - Polycarbox -Master Mix Design 3.8 Glanium Sky 8663 Minutes Slump, mm Measure % Compressive Strength Concrete Durability Tests @ 28 days 0 140 Age N/mm2 Test Value 30 130 Bleeding 1.2 15 hrs 15.4 RCPT, Coulombs 625.05 60 110 Air 7 Days 49.97 0.6 90 70 Content 28 Days 67.23 Permeability, mm 5.22 Plastic Properties Hardened Properties Design Mix – In-situ Concrete at Station Subway Mix Design : M40 Typ. Station Grade Water/ Cementitious 0.26 Constituent Materials Kg / m3 Cement OPC 53 225 GGBS 205 Micro Silica 20 Manuf. Sand - Basalt 911 CA 10mm - Basalt 437 CA 20mm - Basalt 663 Water 143 Admix - Polycarbox Mix Design Mix 6.53 –Auramix 400 Minutes- Slump, mm Measure % Compressive Strength Concrete Durability Tests @ 28 days 0 Collapse Age N/mm2 Test Value 60 180 Bleeding 1.5 RCPT, Coulombs 703 120 170 7 Days 36.71 Air 0.4 Permeability, 150 130 28 Days 61.26 4.33 Content mm Plastic Properties Hardened Properties QUALITY CONTROL WORKMANSHIP and CERTIFICATION Batching Control And Durability Tests – MML3 Batching Plant Control Room Screen • Automated Functioning Checks • Calibration of Plant Water Permeability Rapid Chloride Permeability Test Tunnel Lining Segments - Curing White Resin Curing Compound Steam Curing for speedy production Precast Segment – Tunnel Lining • Inspection of Segment for Defects • Stacking of Segments • Identification Markings • Fixing & Testing of High-density polyethylene Gasket • Transportation of Segment CONSTRUCTION MONITORING Construction Monitoring • Construction monitoring is done by strong teams from Mumbai Metro Rail Corporation, General Consultant and the Contractors • Conformity to Contract Documents, approved Inspection & Test Plans, Method Statements and Standards • Imposed with instruments like Request for Inspections, Non- Conformance Reports, Contractor Surveillance Reports, Corrective Action Reports and other Formats and Registers • Underscoring nodal targets like Hold Points, Witness Points and Observation Points over materials and the workmanship • Regular Site Quality Walks and Quality Meetings • Routine Quality Audits and Contractor Surveillance Inspections • Round-the-clock Construction Team’s imposition on site activities CHALLENGES/RISKS Risks - Manufactured Sand Quality in Mumbai Situation 1. Quarry extraction process and its quality were hardly checked 2016 2. Crushing Process equipment produce unwanted particles Impact Non Conformity to Specifications and significant cracks Quarry Crusher plant Quality Additional Approval Measures verification verification System process process New Initiatives Situation 1. Elimination of Plastic Cracks Sept 2017 2. Improvement in Strength by 18% and RCPT by 59% Risks - Lack of skilled workmen Thank you .