IRC:SP:116-2018 GUIDELINES FOR DESIGN AND INSTALLATION OF GABION STRUCTURES (The Official amendments to this document would be published by the IRC in its periodical, ‘Indian Highways’ which shall be considered as effective and as part of the Code/Guidelines/Manual, etc. from the date specified therein) INDIAN ROADS CONGRESS 2018 IRC:SP:116-2018 GUIDELINES FOR DESIGN AND INSTALLATION OF GABION STRUCTURES Published by: INDIAN ROADS CONGRESS Kama Koti Marg, Sector-6, R.K. Puram, New Delhi-110 022 MAY, 2018 Price : ` 600/- (Plus Packing & Postage) IRC:SP:116-2018 First Published : May, 2018 (All Rights Reserved. No part of this publication shall be reproduced, translated or transmitted in any form or by any means without the permission of the Indian Roads Congress) Printed by India Offset Press, Delhi - 110 064 500 Copies IRC:SP:116-2018 CONTENTS Page S. No. Description No. Personnel of the Bridges Specifications and Standards Committee i-ii Background 1 1. Introduction 2 2. Scope 3 3. Elements of Gabion 3 3.1 Mechanically Woven, Double-Twisted Hexagonal Wire Mesh Gabions 3 3.2 Polymeric Gabions 4 3.3 Revet Mattress 5 3.4 Prefilled Gabions / Revet Mattress 6 4. Components of Gabion Retaining Wall 6 4.1 Technical Specification of Gabion / Revet Mattress Mesh 6 4.2 Rocks for Filling the Gabion 11 4.3 Filter Media 12 4.4 Foundation and Backfill soil properties 15 5. Soil Reinforcement Units for Retaining Structure 16 6. Design Principle of Gabion Retaining Wall 20 6.1 Drainage Bay for Gabion 22 6.2 Base Width 23 6.3 Embedment Depth 23 6.4 Batter Angle 23 6.5 Loading 23 6.6 Porosity of Gabion 24 6.7 Extent of Backfill 24 6.8 Stability of A Retaining Structure 24 6.9 Determination of Active Thrust 26 6.10 Safety against Sliding 27 6.11 Safety against Overturning 28 6.12 Safety against Bearing 30 6.13 Safety against Internal Failure 32 6.14 Safety against Overall / Global Failure 32 7 Design Principle of Gabion / Revet Mattresses 33 7.1 Design Data 33 7.2 Thickness of the Mattress 34 7.3 Tractive Force Theory 34 7.4 Design of Launching Apron 35 7.5 Lining Application Carried out under Water 37 7.6 Structure with Deep Foundation 38 7.7 Structure Built on Loose Rock or Cylindrical Gabion Platforms 38 7.8 Structure Built on Replaced Soil 39 8. Installation Methodology Of Gabion 40 8.1 Some Causes of Failure of Gabion Retaining Walls 46 8.2 Under Water Installation Sequence for Gabion / Revet Mattress 46 8.3 Method of Lifting and Placement of Revet Mattress or Pre-Filled 48 Gabions 8.4 Check List of Site Preparation 48 8.5 Check List for Installation of Gabion 49 9. References 50 Annexure-I: Item Description of DT Products 51 Annexure-II: Details of Thickness of Gabion Mattress in Relation to Water Velocity 54 IRC:SP:116-2018 PERSONNEL OF THE BRIDGES SPECIFICATIONS AND STANDARDS COMMITTEE (as on 23rd October, 2017) 1 Kumar, Manoj Director General (Road Development) & Special Secretary to Govt. (Convenor) of India, Ministry of Road Transport and Highways, New Delhi 2 Singh, B.N. Additional Director General, Ministry of Road Transport & Highways, (Co-convenor) New Delhi 3 Verma, Dr.S.K. Chief Engineer S&R, Ministry of Road Transport & Highways, (Member-Secretary) New Delhi Members 4 Alam, Pervez Chief Operating Officer, Hindustan Construction Company Ltd. 5 Arora, D.S. Jt. Managing Director (Retd.), UP State Bridge Corporation Ltd. 6 Banerjee, A.K. Member (Technical) (Retd.), National Highway Authority of India 7 Bansal, Shishir Chief Project Manager, Delhi Tourism, DTTDC Ltd. 8 Basa, Ashok Managing Director, CEM Consultant (P) Ltd. 9 Bhowmick, Alok Managing Director, B&S Engineering Consultants Pvt. Ltd., UP 10 Bordoloi, A.C. Commissioner & Spl. Secretary, P.W.B. & N.H. Deptt (Retd.), PWD Assam 11 Chand, Faqir Advisor, STUP 12 The CMD, Engg. Proj. (I) Ltd. Engineering Project (India) Ltd., New Delhi (Bakshi, S.P.S.) 13 The Director General, BRO Border Roads Organization, New Delhi (Shrivastava, Lt. Gen. S.K) 14 The Director General, Institute for Steel Development & Growth (INSDAG), Kolkata INSDAG (Banerjee, Sushim) 15 Dheeraj Superintending Engineer, Ministry of Road Transport and Highways, New Delhi 16 Dohare, R.D. Chief Engineer (Retd.), Ministry of Road Transport and Highways, New Delhi 17 The Engineer-in-Chief, MES Military Engineer Service (MES), New Delhi (Sharma AVSM, Lt. Gen. Suresh) 18 Ghoshal, A. Principal Advisor, STUP Consultants (P) Ltd. Kolkata 19 Gupta, Dr. Supratic Asst. Professor, IIT, New Delhi 20 Heggade, V.N. Vice President, Gammon Engineers & Contractors, Mumbai 21 Khanna, Shobha Manager, M.P. Metro Rail Corporation 22 Kondai, Bikshapathi Director General, National Academy of Construction, Hyderabad 23 Kumar, Ashwani Superintending Engineer, Ministry of Road Transport and Highways, New Delhi 24 Kumar, Satander Scientist (Retd.), CRRI i IRC:SP:116-2018 25 Pandey, A.K. Superintending Engineer, Ministry of Road Transport and Highways, New Delhi 26 Pandey, R.K. Member (Project), National Highway Authority of India (NHAI), NewDelhi 27 Parameswaran, Dr. Lakshmy Chief Scientist (BAS), Central Road Research Institute (CRRI), New Delhi 28 Patankar, V.L DG(RD)&SS (Retd.), Ministry of Road Transport and Highways, New Delhi 29 Pateriya, Dr. I.K. Director (Technical), National Rural Road Development Agency, New Delhi 30 Puri, S.K. DG(RD)&SS (Retd.), Ministry of Road Transport and Highways, New Delhi 31 Raina, Dr. V.K. Consultant, World Bank 32 Raizada, Pratap S. Senior Vice President, Gammon India Ltd. Mumbai 33 Sharan, G. DG(RD)&SS (Retd.), Ministry of Road Transport and Highways, New Delhi 34 Sharma, R.S. Managing Director, M/s STP Ltd., New Delhi 35 Shekhar, Saurav Director, SA Infra Consultants Pvt. Ltd. 36 Sinha, N.K. DG(RD)&SS (Retd.), Ministry of Road Transport and Highways, New Delhi 37 Srivastava, A.K. Chief Engineer, Ministry of Road Transport and Highways, New Delhi 38 Subbarao, Dr. Chairman & Managing Director, Construma Consultancy (P) Ltd. Harshavardhan Mumbai 39 Tandon, Mahesh Prof. Managing Director, Tandon Consultants (P) Ltd., New Delhi 40 Verma, G.L. Managing Director, Engineering & Planning Constructions, New Delhi Corresponding Members 1 Kand, Sunil C. Director, C.V Kand Consultant, Bhopal 2 Koshi, Ninan DG(RD)&SS (Retd.), Ministry of Road Transport and Highways, New Delhi 3 Manjure, P.Y. Director, Freyssinet Prestressed Concrete Company Ltd (FPCC), Mumbai 4 Reddi, Dr. S.A. Former JMD GIL 5 The Director, SERC, TN (Iyer, Prof. Nagesh R) Ex-Officio Members 1 President, (Pradhan, N.K.) Indian Roads Congress E-in-C cum Secretary, Works Department, Odisha 2 Honorary Treasurer, (Kumar, Manoj) Indian Roads Congress Director General (Road Development) & Spl. Secretary, Ministry of Road Transport and Highways 3 Secretary General, Nirmal, Sanjay Kumar Indian Roads Congress ii IRC:SP:116-2018 GUIDELINES FOR DESIGN AND INSTALLATION OF GABION STRUCTURES BACKGROUND The Foundation, Sub-Structure Protective Works and Masonry Structures Committee (B-3) constituted a sub-committee comprising of the following to draft the document: Shri Sharad Mahiaiskar ……...... Convenor Shri PL Bongirwar ……...... Member Dr N.V. Nayak ……...... Member Shri S. Ray ……...... Member Shri RK Jaigopal ……...... Member Shri Dilip Karamdhikar ……...... Member Dr. Ratnakar Mahajan ……...... Member Shri Sarokh Bagli ……...... Member The sub-committee deliberated extensively and draft was presented before the B-3 Committee several times. The committee finalized the draft “Guidelines for Design and Installation of Gabion Structure” during its meeting held on 09.09.2017 for placing before the BSS Committee. The draft was considered by the Bridges Specifications and Standards Committee (BSS) in its meeting held on 23.10.2017 and approved the document. The document as approved from BSS Committee was placed before the IRC Council in its 213th meeting held on 03.11.2017 at Bengaluru (Karnataka). The Council approved the document. The Foundation, Sub-Structure Protective Works and Masonry Structures Committee (B-3) of the Indian Roads Congress was constituted in 2015 with the following personnel: Sharma, R.S. ……...... Convenor Arora , Daljeet Singh ……...... Co-Convenor Jain, Sanjay Kumar ……...... Member Secretary Members Bagali, Sharokh Gaharwar, Dr. S.S. Basa, Ashok Ganguly, Arindom Bongirwar, P.L. Huda, Y.S. Jaigopal, R.K. Prakash, R. Joglekar, S G Rana, Dr. Sanjay Kanhere , Dr. D.K. Ray, S. Karandkar, Dilip Saha, Dr. G.P. Khanna, Ms. Shobha Sinha, A.K. Mahajan, Dr. Ratnakar Srivastava, S.K. Marwah, M.P. Subbarao, Dr Harshavardhan 1 IRC:SP:116-2018 Mhaiskar, Dr. Sharad Viswanathan, T. Nayak, Dr. N.V. Parvathareddy, Venkat Mayur B Corresponding Members Kand, Dr. C.V. Manjure, P.Y. Ex-Officio Members President, IRC DG(RD) & SS MORTH (Pradhan, N.K.) (Kumar, Manoj) Secretary General, IRC (Nirmal, S.K.) 1 INTRODUCTION A Gabion structure is prepared from pre-assembled rectangular cages made of double twisted steel woven wire mesh filled with rocks/ boulders. It is a simple gravity retaining structure, which retains soil with its weight. These types of structures are in use in highways, bridges, canal linings, buildings, shore protection works, etc., as shown in Fig. 1a to d. The porosity of gabions prevents the pore-water pressure development behind the walls which, is one of the major advantages of these kinds of systems. These structures blend with the surroundings and allow vegetation to take roots through the structure which enhances the life of the structure. Reduced carbon foot prints are also a noticeable feature when compared to conventional solutions. Fig. 1a Soil Retaining behind an Abutment Fig. 1b Apron Works 2 IRC:SP:116-2018 Fig. 1c Shore / Bank Protection Fig. 1d Bridge Abutment Protection 2 SCOPE These guidelines cover the specifications, design principles and installation methodology for Gabion and Revet Matresses for use in highway and bridge structures. 3 ELEMENTS OF GABION Following sections describe the characteristics of the materials used in construction of gabion walls. In addition to the gabion elements, the performance of the gabion structure hinges on the properties of infill, retained fill and the rockfill and other components and measures for efficient design and adoptability. 3.1 Mechanically Woven, Double-Twisted Hexagonal Wire Mesh Gabions Gabion is rectangular box made from mechanically woven double twisted hexagonal mesh filled with rock or stones (Fig. 2c). A terminal wire is used to edge the wire mesh perpendicular to the double twist by mechanically wrapping the mesh wires around it at least 2.5 times (Fig. 2a).The hexagonal shape of the mesh helps in achieving uniform distribution of forces. Mesh should be non-corrosive and should possess high tensile strength. The details of the different mesh types, sizes and various tests are available in IS 16014 and are reproduced in and Table 3. The wires of the mesh should be galvanised with zinc and/or polymeric (coating like Polyvinyl Chloride (PVC), Polyamide (PA6), other polymer etc.) coated to prevent corrosion. Better coatings of Zn Al alloy like Zn 95% Al 5% and Zn90% Al 10% are used which are better than only Zinc. Similarly better polymeric coatings like polyamide are used. 3