Emerging Innovative Solutions Enhancing Practical Geotechnical Engineering
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Missouri University of Science and Technology Scholars' Mine International Conference on Case Histories in (2008) - Sixth International Conference on Case Geotechnical Engineering Histories in Geotechnical Engineering 15 Aug 2008, 1:30 pm - 3:00 pm Emerging Innovative Solutions Enhancing Practical Geotechnical Engineering Shubhada S. Jagtap Maccaferri Environmental Solutions Pvt. Ltd., India Annapurni Iyer Maccaferri Environmental Solutions Pvt. Ltd., India Minimol Korulla Maccaferri Environmental Solutions Pvt. Ltd., India Follow this and additional works at: https://scholarsmine.mst.edu/icchge Part of the Geotechnical Engineering Commons Recommended Citation Jagtap, Shubhada S.; Iyer, Annapurni; and Korulla, Minimol, "Emerging Innovative Solutions Enhancing Practical Geotechnical Engineering" (2008). International Conference on Case Histories in Geotechnical Engineering. 3. https://scholarsmine.mst.edu/icchge/6icchge/session11b/3 This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License. This Article - Conference proceedings is brought to you for free and open access by Scholars' Mine. It has been accepted for inclusion in International Conference on Case Histories in Geotechnical Engineering by an authorized administrator of Scholars' Mine. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. EMERGING INNOVATIVE SOLUTIONS ENHANCING PRACTICAL GEOTECHNICAL ENGINEERING Shubhada S Jagtap Annapurni Iyer Minimol Korulla Engineer Design, Manager (Designs), GM- Designs & Maccaferri Env. Sol. Pvt. Ltd., Maccaferri Env. Sol. Pvt. Ltd., Chief of World Design Center, 1003, Cassablanca, CBD Belapur, 1003, Cassablanca, CBD Belapur, Maccaferri Env. Sol. Pvt. Ltd., Navi Mumbai – 400614. Navi Mumbai – 400614. 1003, Cassablanca, CBD Belapur, Maharashtra, India. Maharashtra, India. Navi Mumbai – 400614, Maharashtra, India. [email protected] [email protected] [email protected] ABSTRACT This paper presents two case histories, wherein double twisted hexagonal wire mesh crates and netting were used as a solution for geotechnical problems that aroused while execution. One of which is worldwide known and one of the most prestigious projects of India - Konkan Railway, and second is internationally noted tourist spot- Amby Valley Sahara lake city. In Konkan Railway project, double twisted wire mesh was used as a basic material for variety of problems like rock fall prevention, Gravity walls at the base of rock slopes, Baby Gabions as ballast retention for railway tracks, Platform Gabions etc. Adoption of Gabions and rock fall netting was one of its types of innovative solutions for this project. For Amby Valley Sahara lake city project, global instability of high cuttings in soil and heavy landslides were the major geotechnical problems. Many traditional solutions have failed at the site. Gabion retaining walls were adopted of heights ranging from 2 m to 13 m. Though there were initial failures mainly due to faulty construction, the same system of Gabion walls was continuously adopted due to its flexible, permeable and environment friendly nature. INTRODUCTION conventional solution may not serve the purpose and need of innovative techniques arises. Civil Engineers always come across critical problems with unique site conditions. Many a times, instead of following the Case histories of Konkan Railway project and Amby Valley same path of traditional solutions, they may need to adopt Sahara lake city project are discussed in subsequent innovative ideas which will best suit as the problem solution paragraphs with respect to project brief introduction, with economy and utmost effectiveness. geotechnical problems faced while execution and solutions adopted. As far as Geotechnical Engineering is concerned, the intensity of such critical problems is more, as we, Geotechnical Engineers, need to deal with soil, rock and inside strata of the KONKAN RAILWAY PROJECT, MAHARASHTRA, earth to study the particular site, before going for construction. INDIA Many uncertainties always persist with unique characteristics of each region. But, for all major and important civil engineering works, such Geotechnical surveys and relative Project Brief History studies are highly necessary. Until Konkan Railway started its operations, the two important While executing any such projects, the documentation of the port cities Mangalore (in Karnataka State of India) and experience, new learning and many innovative solutions Mumbai (in Maharashtra State of India) were not directly adopted successfully, can be kept and referred back as a Case connected by the railway network. Even though economic History in future. Case histories play an important role to reasons provided a strong need to connect these two cities, the arrive at a solution, not only for practicing engineers as a region through which the railway track passed was guide, but also for professors and students as a reference geographically very tough and would be an engineering literature and sometimes also for experienced professionals in challenge. the field. In Geotechnical Engineering practice, designers many times come across a problem, for which giving the Paper No. 11.10b 1 The Konkan Railway is the first railway project in India, formidable terrain and the short construction period which was taken on ‘BOT’ (Build-Operate and Transfer) necessitated the use of several technological innovations. The concept. The 760 km long Konkan Railway route passes construction and widening of the track called for large through large number of cuttings, tunnels, bridges and quantities of cutting in rocks of lateritic and basaltic origin. embankments, in Maharashtra, Goa and Karnataka states of The exposed lateritic terrains are subjected to heavy rainfall India, along foothills of Western Ghat section and west coast. and in the presence of water; the laterite loses all of its The work in construction began in in the year 1990, and the cohesiveness, strength and become very vulnerable to cause entire rail line from Roha (Maharashtra) to Thokur heavy slides and slips. This further called for the necessity of (Karnataka) was commissioned on 1 st May 1998. With the proper retaining walls and rock fall prevention measures. construction of this Broad Gauge line, the rail distance from Mumbai (Bombay) to Mangalore and Delhi to Mangalore has Another problem was the limited space available for the been significantly reduced. tracks. The ballast which is laid below the tracks primarily serves the purpose of load dispersion apart from giving added The client of this project was Konkan Railway Corporation resilience. Conventionally, a ballast layer of depth 250 mm is Limited (KRCL) and number of small contractors were adopted below the sleepers with a depth of 500mm on the involved to carry out the works. sides, sloping outwards. This requires a greater utilization of space on the sides, with sufficient width for embankment. The task was formidable. As Karlis Goppers pointed out in Further over a period of time, due to the repeated use of track, his Swedish International Development Cooperation Agency the ballast has a tendency to roll out of tracks. Also, as an (SIDA) report in July 1997: With a total number of 2,000 innovative solution and for speedy construction, Gabions were bridges and 92 tunnels to be built through this mountainous used to construct the platforms of various stations along the terrain containing many rivers, the project is the biggest and route. perhaps most difficult railway undertaking during this century, at least in this part of the world. The various problems had There have been many instances of boulder/ rock falls and been carried out efficiently and in a very short time. rock slips in small quantities from the rock cutting slopes towards the track, particularly in monsoon period. The trains have hit the infringed / fallen boulder over the track and Geotechnical Data of the Terrain caused damage to cattle guard / loco and even to rail track /Sleepers. In order to prevent such isolated boulder fall / small The terrain through which Konkan Railway passes consists rock slips, innovative and cost effective measure, namely, mainly of Basaltic rocky strata due to presence of Sahyadri ‘Boulder netting’ over the rock slopes have been extensively mountains, and lateritic soil. As the railway line is parallel to used in vulnerable and high depth cutting locations. Boulder the western coast from Mumbai to Mangalore, the entire netting solution is mainly identified only in the locations, terrian is subjected to heavy rainfall (around 3000 to 4000 (i) Where the rock strata is fairly strong, but jointed and mm) in the monsoon season. These Basalt rocks are igneous, blocky in nature, with no definite pattern / orientation of extrusive rocks which have been erupted as lava flows, about joints. millions of years ago from deep inside the earth and spread on (ii) Where rock mass is shattered with wide /deep and uneven the surface of different layers. Over hundreds of years, the top cracks, which cannot be removed by loose scaling. cover of the Basalt rock has been subjected to weathering, (iii) Where big size sub rounded boulders are seen in top rock thereby forming a red laterite soil crust of variable thickness slopes, partially embedded in laterite soil. on top of the rock. The main engineering problems