Construction of Flyover

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<p>MALVIYA NATIONAL INSTITUTE OF TECHNOLOGYJAIPUR</p> <p>TRAINING REPORT ON</p> <p>CONSTRUCTION OF FLYOVER AT TRANSPORT NAGAR CIRCLE (JAIPUR)</p> <p>About JDAJaipur Development Authority (JDA) has been committed to working for the benefit of the citizens of Jaipur with planned implementation of development schemes and is consistently striving to take Jaipur at higher levels of progress. Jaipur is one of the most well-planned cities of its times and planned development has always been central to its ideology. Jaipur Development Authority came into existence by the Government of Rajasthan with a vision to combat and manoeuvre</p> <p>the growing requirements of a large city in wake of the increasing population and to help give Jaipur a planned look compatible and comparable to any metropolitan city of repute. JDA was authorised powers and a green signal to speed up the development and progressive growth of the entire city to rapidly change the face of Jaipur. To meet these important needs JDA sprang into action and started to understand the necessary needs of the city. According to the requisites, JDA has been working towards timebound construction, creation and development of the western part of Jaipur based on major scientific and hi-tech strategies. Thus, Jaipur has been beautified intensively to augment the tourist attraction in the city and to raise the living standards to suit convenience of its citizens. The major undertaking of JDA includes the following: * Infrastructural development of Jaipur region by construction of flyovers, bridges, parking places. * Development of commercial projects and residential schemes, etc. * Development of basic amenities like community centres, parks, ring roads. * Development and rehabilitation of kacchi bastis etc. * Preparation and implementation of master plan. * Preparation and implementation of guidelines for colonisation. * Environmental development by planning and implementing roadside plantations and by developing eco-friendly schemes. * Development of rural area around Jaipur. * Development of transport facilities like Mass Rapid * Transport System (MRTS), Transport Nagar, and major sector roads.</p> <p>According to the promises and commitments of the Rajasthan Government, JDA has been time and again proving itself as a pioneer of development, creating a state-of-the-art city of substance. JDA has been working on widening all main roads, construction of over bridges, under bridges and flyovers to regulate the traffic on roads, minimize pollution, and ensure public convenience and safety. JDA firmly believes in bridging the gap and reaching out to its citizens and to provide them with quick and hassle-free service.</p> <p>Contents 1. Introduction 2. Components of flyover i) ii) Foundation Piers and abutments</p> <p>iii) Deck iv) Pre-stressed concrete v)3.</p> <p>Backfill and Reinforced earth wall</p> <p>Underpass and Construction of Diaphragm wall</p> <p>Construction of Flyover at Transport Nagar Circle(Jaipur)INTRODUCTION Transport Nagar Chouraha is one of the gateways to Jaipur on junction of NH-8 (From Delhi) and NH-11 (From Agra). With the view to ease out the traffic congestion at this important junction , after evaluating various options JDA has undertaken construction of three level grade separator at the crossing. The proposal is to construct underpass towards MI Road- Agra side and flyover from Delhi side with one leg flying towards MI Road (Flyover-1) and other towards Jawahar Nagar Bypass road (Flyover-2) along with slip lanes on all the four sides. The other instruments of junction improvement along with improvement of drainage system of the area as well as for new constructed elements are part of the project. Some of the elements like Diaphragm wall, for construction of underpass, will be constructed for the first time in Jaipur and perhaps Rajasthan. The administrative &amp; financial sanction amounting to Rs. 71.25 Crore has been approved for the project. M/s Span Consultants have been engaged as the consultants for the Project. The Proof check of the structural design is being done by Structural Department of Malaviya National Institute of Technology, Jaipur. M/s Petron Supreme (JV) have been awarded work order amounting to Rs. 64.98 Crores for the project with stipulated period of completion as 24 months. The work actually commenced in the month of June.09. Presently , the work of all the three components namely Flyover-1, Flyover-2 and underpass is going on in full swing. All the piers (17 Nos.) of Flyover-1 have been completed and placing of PSC Girders has</p> <p>commenced. In Flyover-2, 17 out of 19 piers have been completed. The work of retaining wall (Diaphragm wall) is also continuing in satisfactory pace. Presently, works amounting to Rs. 16.00 Crores have been completed. The Flyover-1 from Delhi Road towards MI Road is scheduled to be completed by Sept. 10. The Flyover-2 from Delhi towards Jawahar Nagar Bypass is scheduled for completion in Dec.10. The project will be concluded with construction of Underpass towards MI Road-Agra direction by June 2011.</p> <p>Salient Features Project Cost Agency Consultant Delhi Date of commencement Stipulated date of completion : Rs 67.67 Crores : Petron Supreme (JV) : Span Consultant Pvt Ltd., : 03.10.2008 : 02.10.2010</p> <p>Physical Features1. 2. 3. 4. 5. 6. 7. 8. Total Length of the Flyover Total Length of Underpass Vertical Clearance of Underpass Width of Underpass Width of Flyover Nos. of Viaduct Length of Viaduct 565.20 m 365.00 m 5.50 m 19.90 m 20.50 m 1+10 Nos 46.70 / 21.20 m</p> <p>Length of both side approaches of 305.0 m</p> <p>Flyover 9. Type of Structure (Flyover) Box Girder in Obligatory</p> <p>Span/Precast PSC Girders with RCC slab on remaining spans 10 Type of Structure (Underpass) Diaphragm wall with Precast PSC Girders and RCC solid slab</p> <p>5. SOURCE OF MATERIAL: S.No. Material 1. 2. 3. 4. 5. Stone aggregates Coarse Sand Cement Bitumen Source Delhi Road River Banas Any ISI Marked regular brand OPC / PPC Mathura Refinery</p> <p>Selected fill for R.E River Dund bed Wall</p> <p>6.</p> <p>Reinforcement Steel</p> <p>Any Original Manufacturer confirming to relevant IS Code</p> <p>7.</p> <p>Admixture</p> <p>Fosroc , Choksey or equivalent</p> <p>SOME IMPORTANT THINGS!!!</p> <p>1) Always wear a good quality helmet on the site.</p> <p>2) Always wear shoes on the site.</p> <p>3) Wear safety belts if required.</p> <p>4) Safety nets should be provided wherever it is necessary.</p> <p>MAJOR COMPONENTS OF FLYOVER FOUNDATION Since the bridge has to carry a big live load and its dead weight is also very large so we cannot go for simple foundation but pile foundation. Pile foundation is one type of deep foundation. It is used where the good soil is at higher depth (10 or 15m) or soil having low bearing capacity. Pile is also used for tall structures. In pile foundation the load coming from the super structure is taken by pile cap and equally distributed in no of piles, pile transfers this load into the soil. At Transport Nagar Flyover Pile foundation is proposed for piers and abutment. The piles are 1200 mm dia , 20 m depth M-35 grade cast in situ piles. The pile cap is proposed of M-35 grade. Detailed arrangement of pile is shown in attached Bottom Plan (Courtsey:Span Consultants)</p> <p>INSTALLATION PROCEDURE OF PILES Step 1 --- Excavation of Pile Shaft The bored pile equipment set including hydraulic oscillator, hydraulic vibrator, hammer grab and rock chisel used in this project is very common and being widely used for shaft excavation. a. Set out the correct position of the bored pile on site. b. Excavate about 3 - 4m of the pile to remove shallow obstructions and then backfill, wherever necessary. c. Install the bottom section of temporary casing of required diameter into the ground by oscillating and jacking or by</p> <p>vibrating motion exerted by the oscillator and the vibrator respectively. d. Set up hydraulic oscillator or vibrator in conjunction with a crawler crane. e. Excavate within the casing by hammer grab and redrive the steel casing simultaneously by using the heavy duty casing oscillator / vibrator. Rock chisel in various types will be employed for removal of obstruction or hard materials during the above process. f. Extend the steel casing by bolting or welding on additional casing during the excavation. g. Water will be pumped into the casing during excavation and constant water head will be maintained so as to prevent any ingress of material from the bottom of casing. h. Verticality of the casing will be monitored by means of spirit level from time to time. i. Continue the above procedure until the founding level of pile has been reached .j.</p> <p>Pile base enlargement will be formed by employing a bellout chisel or a reverse-circulation drill as indicated in the working drawings.</p> <p>Step 2 --- Cleaning of Pile Shaft Final cleaning will be carried out by the air-fitting method using high pressure air compressors. The slime and muddy water within the casing will be cleared and delivered into a desilting tank before discharge. Step 3 --- Tremie Concreting</p> <p>a. The pile shaft will be concreted by "Underwater Tremie Technique". The tremie pipe sections will be inserted and be jointed until it reaches the bottom of pile shaft. Concrete will be poured into the tremie pipe by using a concrete skip. Concreting will be carried out in one continuous operation until the required level has been reached. b. As concreting proceeds, the level of the concrete relative to the ground level will be monitored by measuring with weighted tape after each skip of concrete is placed. c. The base of the tremie pipe will be kept with a minimum depth of approximate 1 to 2m below the surface of the concrete. d. The temporary casing will be extracted simultaneously by the oscillator in the course of concreting. A head is always maintained between the top of concrete and the bottom of steel casing.</p> <p>Step 4 --- Installation of Reinforcement After the completion of concreting, dowel bars of required length and numbers will be installed into the pile shaft and down to the predetermined level before the extraction of bottom steel casing.</p> <p>PIERS &amp; ABUTMENTS The Transport Nagar flyover-1 has 17 piers including two abutments and Flyover-2 has 19 piers including two abutments. The maximum height of the pier for Flyover-1 is about 9 m and for Flyover-2 is 7m .The piers are M-35 grade rectangular pullers. Details are shown in Top Plan and Sectional Elevation (Courtsey: Span Consultants).</p> <p>Piers under construction</p> <p>DECK The Superstructure is M-40 Grade Deck Slab over precast post tensioned concrete girders in M-40 Grade Concrete. Antiskid bituminous mastic course 25 mm in thickness is proposed over RC C wearing course. Approaches: RE wall is proposed in approaches. Gravitational drainage backed by forced system comprising of suitable pump and appurtenances is proposed for underpass drainage. The span length is of range of 25 m to 50 m. A typical section of superstructure pier and pile is shown in figure. Pre-stressed Concrete The technique of pre-stressing eliminates cracking of concrete under all stages of loading and enables the entire section to take part in resisting moments. As dead load moments are neutralized and the shear stresses are reduced, the sections required are much smaller than in reinforced concrete. Prestressing can be accomplished in three ways: pre-tensioned concrete, and bonded or unbonded post-tensioned concrete. Pre-tensioned concrete</p> <p>Pre-tensioned concrete is cast around already tensioned tendons. This method produces a good bond between the tendon and concrete, which both protects the tendon from corrosion and allows for direct transfer of tension. The cured concrete adheres and bonds to the bars and when the tension is released it is transferred to the concrete as compression by static friction. However, it requires stout anchoring points between which the tendon is to be stretched and the tendons are usually in a straight line. Thus, most pretensioned concrete elements are prefabricated in a factory and must be transported to the construction site, which limits their size. Pretensioned elements may be balcony elements, lintels, floor slabs, beams or foundation piles. Bonded post-tensioned concrete Bonded post-tensioned concrete is the descriptive term for a method of applying compression after pouring concrete and the curing process (in situ). The concrete is cast around plastic, steel or aluminium curved duct, to follow the area where otherwise tension would occur in the concrete element. A set of tendons are fished through the duct and the concrete is poured. Once the concrete has hardened, the tendons are tensioned by hydraulic jacks that react against the concrete member itself. When the tendons have stretched sufficiently, according to the design specifications (see Hooke's law), they are wedged in position and maintain tension after the jacks are removed, transferring pressure to the concrete. The duct is then grouted to protect the tendons from corrosion. This method is commonly used to create monolithic slabs for house construction in locations where expansive soils (such as adobe clay) create problems for the typical perimeter foundation. All stresses from seasonal expansion and contraction of the underlying soil are taken into the entire tensioned slab, which supports the building without significant flexure. Post-tensioning is also used in the construction of various bridges; both after concrete is cured after support by falsework and by the assembly of prefabricated sections, as in the segmental bridge.</p> <p>The advantages of this system over unbonded post-tensioning are: 1. Large reduction in traditional reinforcement requirements as tendons cannot destress in accidents. 2. Tendons can be easily 'weaved' allowing a more efficient design approach. 3. Higher ultimate strength due to bond generated between the strand and concrete. 4. No long term issues with maintaining the integrity of the anchor/dead end. Unbonded post-tensioned concrete Unbonded post-tensioned concrete differs from bonded posttensioning by providing each individual cable permanent freedom of movement relative to the concrete. To achieve this, each individual tendon is coated with grease (generally lithium based) and covered by a plastic sheathing formed in an extrusion process. The transfer of tension to the concrete is achieved by the steel cable acting against steel anchors embedded in the perimeter of the slab. The main disadvantage over bonded post-tensioning is the fact that a cable can destress itself and burst out of the slab if damaged (such as during repair on the slab). The advantages of this system over bonded post-tensioning are: 1. The ability to individually adjust cables based on poor field conditions (For example: shifting a group of 4 cables around an opening by placing 2 to either side). 2. The procedure of post-stress grouting is eliminated. 3. The ability to de-stress the tendons before attempting repair work.</p> <p>In Tr...</p>