Acknowledgement I owe a great many thanks to many people who helped and supported me during the period of my internship and the writing of this report. My deepest thanks to Mr. Titare, the Project Manager of the Kapurbawdi Bhandup Tunnel Project for allowing me to complete my internship in this particular project. My deep deep sens sensee of grat gratit itud udee to Mr. Mr. Desh Deshpa pand nde, e, Mr. Mr. Andu Andure re,, Mr. Mr. Akre Akre from from the the Civi Civill Department; Mr. Devidas and the whole Surveyor Group, Mr. Chetan Shetty and Mr. Gunjan Disawal from Planning Department; Mr. Kate from Billing; Mr. Kulkarni from PMC Department; Mr. Hari and Mr. Pandurangarao from the Safety Department for their help and guidance. Thanks and appreciation to all the helpful people on the site and for their constant support. I would also extend my heartfelt thanks to my family and well wishers without whom this project would have been a distant reality. Date: 07/07/2011 Abhishek Sarkar
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Table of Contents Acknowledgement...........................................................................................................................1 Details of the project: -....................................................................................................................3 Scope of work: -...............................................................................................................................3 Daily Activities: -.............................................................................................................................5 Cycle of Daily Activities: -.........................................................................................................5 Details of the Daily Activities: -..................................................................................................5 Surveying:...............................................................................................................................5 Drilling:..................................................................................................................................6 Blasting Material Loading and Charging:..............................................................................6 Blasting and Venting: ............................................................................................................7 Loose Scaling: .......................................................................................................................7 Mucking: ................................................................................................................................7 Geological report of the site: -.........................................................................................................8 Execution of project: -.....................................................................................................................9 The shaft:.....................................................................................................................................9 Assembly Tunnel and Tail Tail Tunnel:........................................................................................ ....10 Placing of Ribs:.........................................................................................................................11 Construction of Retaining Wall:................................................................................................12 Planning on site: -..........................................................................................................................13 Safety: -..........................................................................................................................................16 Conclusion: -..................................................................................................................................19
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PROJECT REPOR REPORT T Name of Project: - Tunnel Excavation Excavation from Gundovli to Bhandup Details of the project: The project is divided mainly in two parts. The first section is called Section A and the next is called Section B. Section A is from Gundovli to Kapurbawdi and Section B is from Kapurbawdi to Bhandup. This is a project report on the section B, i.e., from Kapurbawdi (K2) to Bhandup. The main focus of this report is on the K2 end.
Scope of work: The scope of work for Section B includes: (a) Construction of 11.8m diameter 108m deep Inlet shaft at Kapurbawdi (K2) and11.8m diameter diameter 125m deep outlet shaft at Bhandup Bhandup by convention conventional al drilling drilling andcontro andcontrolled lled blasting method including disposal of muck and pumping outseepage water. water. (b) (b) Exca Excava vati tion on for for tail tail tunn tunnel el and and TBM TBM asse assemb mbly ly area area,, at bott bottom om of the the shaf shaftt atKapurbawdi (K2) and tail and TBM removal area at Bhandup by drilling andcontrolled blasting method and disposal of muck. (c) Boring of Tunnel from Kapurbawdi(K2) with upward gradient 4.5:1000 byTBM. including including communica communication tion faciliti facilities, es, safety safety measures measures,, lighting,v lighting,ventil entilatio ation, n, dewateri dewatering, ng, wet/dry mucking and its disposal, RCC lining of thetunnel to a finished 5.5 m diameter, Providing 4.9m diameter steel liners as per IS:2002 instead of RCC lining wherever necessary. (d) Probe hole drilling, pre-grouting and post-grouting with cement and/orchemical to control seepage of sub-soil water. (e) Dismantling of TBM and withdrawal of the same through shaft. (f) Concrete backpacking behind steel liner. (g) Supply, Supply, manufacture, laying, jointing and testing MS Pipelines and specialsalong with inside inside and outside outside surface surface treatment treatment including including allied allied civil,mec civil,mechani hanical cal and electric electrical al works. Interconnection of Upper Vaitarna and Diversion Maini to the manifold atKapurbawdi (K2) shaft. Manifo Manifold ld at Bhandu Bhandup p Shaft Shaft for connec connecion ionss to the existi existing ng treatm treatment ent plant plant,, 900Mld 900Mld treatment plant under construction and provision for connecting to futureGargai and Pinjal treatment plants. (h) Providing, supplying and erecting 2400/1800 mm diameter B/F valves alongwith DMJ, DMJ, tapers tapers and companion companion flange. Also Also providing, providing, supplying supplying anderectin anderecting g 200 mm diameter Kinetic Air valves. (i) Provide concrete encasement to pipes etc. (j) Cement mortar lining for internal surfaces of liners & pipelines.
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(k) Backfilling the shafts, assembly and the tail tunnel areas with murum /earth /tunnel muck /plum concrete. (l) Demolition of existing structure (m) Steel Bridge for pipeline. (n) Testing and Commissioning of the Tunnel.
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Daily Activities: Cycle of Daily Activities: 1. 2. 3. 4. 5. 6. 7. 8.
Surveying Drilling Blasti Blasting ng Materi Material al loadin loading g Charging Blasting Venting Loos Loosee scal scalin ing g Mucking
Details of the Daily Activities: Surveying: Surveying is the most essential activity in the daily cycle. Surveying includes checking the reduced levels at 1.00m chainage intervals. It also includes determining the undercut and overcut portions of the tunnel cross-section. Surveying also helps determine how much excavation has been completed and how much is remaining. It also checks the centre line alignment of the excavation to determine and to avoid the excavation going out of route.
Surveying in Progress Instruments used for surveying:
Surveying is done with some equipment. The main and the most important equipments are: 1. Total Station:A total station is an electronic/optical instrument used in modern surveying. The total station is an electronic theodolite (transit) integrated with an electronic distance meter (EDM) to read slope distances from the instrument to a particular point. The major functions of total station are: a. Coor Coordi dina nate te meas measur urin ing g b. b. Dist Distan ance ce mea measu suri ring ng c. Angl Anglee mea measu suri ring ng d. Data Data pro proce cess ssin ing g
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Total Station
Tripod for Total Station
Level: An automatic automatic level level or builde 2. Auto Level: builder's r's auto auto level level includ includes es an intern internal al comp compen ensa sato torr mech mechan anis ism m (a swin swingi ging ng pris prism) m) that that,, when when set set clos closee to leve level, l, automatically removes any remaining variation from level. This reduces the need to set the instrument truly level, as with a dumpy or tilting level.
Automatic Level
Self Self-l -lev evel elin ing g inst instru rume ment ntss are are the the pref prefer erre red d inst instru rume ment nt on buil buildi ding ng site sites, s, construction and surveying due to ease of use and rapid setup time. 3. Telescopic Staff: telescopic staff is used for taking the measurement with dumpy levels and to find out the vertical distance of a point with respect to a horizontal plane. 4. Steel Tapes: Steel tapes are used to measure chainage accurately and to take measurements of small objects accurately. Drilling: After surveying is completed the next step is drilling. Drilling is done pneumatically with with the help of compressed air and water. Both compressed air and water is supplied from the ground surface with the help of pipes and is distributed with the help of manifolds. The drillers drill hole on the rock surfaces according to the plan set by the engineers which is according to the amount of overcut or undercut or how much pull is required. Pull refers to the horizontal progress achieved after blasting. Blasting Material Loading and Charging: After the drillers have completed the number of holes required up to the depth specified by the engineers engineers,, the next step is to fill those holes with blasting blasting material material.. The blasting blasting materi material al used used here here is Super Super Power Power Gel 90 which which is basica basically lly an alumin aluminum um nitrat nitratee
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compound and it comes in thin straight packages. These gels are inserted into the holes and the LDD (long delay detonators) are used to charge the material. LDD is a type of electronic detonator which is designated by numbers, for e.g. No 1 LDD where the number indicates the delay in milliseconds. The holes are then packed with packing material and are made air tight. The site is cleared and then after giving the warning siren the blasting is done. Blasting and Venting: After the sirens are given for warning, the blasts are done using the detonators. The blasts blasts are to be done only between sunrise and sunset. After After blasting a time period of 1.30 hrs to 2 hrs is allowed before entering the shaft and tunnel. After the specified time, the safety personnel enter the shaft with a gas detector and check the H2S and CO levels along with oxygen levels. The normal oxygen level is 20.8 and the H2S and CO content are zero. If the gases go beyond optimal levels the gas detectors gives a warning sound and the shaft is cleared again for another half an hour. The process is repeated until it is fit to work in the shaft. Loose Scaling: Loose scaling of rocks means to check whether any loose pieces of rocks are attached to the tunnel walls. If this is not checked, then it may cause a safety hazard or an accident for the workers in the tunnel. Hence this is a very important step in the daily cycle. Mucking: Mucking refers to the removal of the rocks after the blasting is completed. This clears the work zone so that the next cycle can start again. Mucking is done with the help of poclains and loaders. The rocks are collected and then loaded in muck buckets. These are then brought up to the ground level with the help of gantry crane. After the mucking is completed, the next cycle starts. Surveying is done to determine the pull of the blast and how much work is left.
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Geological report of the site: Extensive geological survey was done at the site during the excavation of the shaft to map the rock details. This geological mapping was aided by petrography examination. The types of rocks encountered were identified and the geological properties of the rocks were also determined. The joints and faults in the rocks were also identified. It was found that there are a total of six sets of joints in the rock mass and it was mapped. The rock type was identified basically as basalt.
Thin Layered Amygdaloidal Basalt with Parallel Quartz Filling
Different types of basalts were encountered like compact basalt, amygdaloidal basalt, small deposit of quartz, tuff basalt and a little amount of volcanic ash. It was determined that the rocks were created during the Upper Cretaceous to Plaegene age. This lies in the Deccan trap and was created by a volcanic eruption. Amygdaloidal basalt is often confused with vesicular basalt. Amygdaloidal basalt has no air gaps, all the gaps are filled with a secondary mineral and it often gives a spotted look. Vesicular basalt on the other hand has air gaps and allows water percolate through it. In geology the term joint refers to a fracture in rock where the displacement associated with the opening of the fracture is greater than the displacement due to lateral movement in the plane of the fracture (up, down or sideways) of one side relative to the other. Basalt is a very common igneous rock. In fact it is the most common rock in the Earth's crust. Almost all oceanic crust is made of basalt and basalt is a common extrusion from many volcanic regions around the world. It forms from the melting of the upper mantle and its chemistry closely resembles the upper mantle's composition. It is generally silica poor and iron and magnesium rich. Basalt originates from "hot spot" volcanoes, massive basalt flows and mid oceanic ridges. Basalt also comes from extensive lava flows. Basalt lava flows are not very viscous (a measure of resistance to flow) and so can flow easily and quickly across great distances delivering great volumes of basaltic rock.
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Execution of project: The project is being executed in the following steps.
The shaft: The shaft at Kapurbawdi end of the tunnel is 108.6 meters deep. The shaft was excavated with the help of drilling and controlled blasting. The initial portion of the shaft was done by excavators and well sinking. Well sinking is done with the help of force of gravity. The first step of well sinking is the making of the cutting edge and the liner plate. Then the reinforcement is done and the concreting of the first lift. An excavator is placed in the the well and the excavation starts. As As the excavation proceeds, the well starts sinking and lifts are added. After the well reaches the rock bed, grouting is done to fill the cracks through the annular plugs. The rest of the shaft is excavated by drilling and controlled blasting. During blasting, the opening of the shaft is covered with metal cover so that the debris does not come out of the shaft and does not damage machineries or the people working on the site. After blasting the muck is collected in the muck bucket and is taken out of the shaft and dumped on the site. From there it is loaded on dumpers and is dumped in specified dumping places. The lead to these dumping sites is measured and is later used for planning and billing purposes. This is done till the shaft reaches the required depth.
The shaft at the Kapurbawdi end is 108.6 meters deep. As the shaft is excavated, arrangements for dewatering is also done so that the seepage water is pumped out and does not deteriorate the progress of the project. As the shaft increases in depth, provisions for air and water is made so that the people working in the shaft do not face any problems in breathing. The shaft walls are stabilised with shotcrete where ever necessary and rock bolts are also used. Shotcrete is done with steel fabrics and without steel fabrics depending on the nature of the shaft wall. If fabrics are used with shotcrete then its depth is 100 mm and it 50 mm if the shotcrete is done without fabrics.
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Assembly Tunnel and Tail Tunnel: According to the tender, an assembly tunnel of 100 meters length and a tail tunnel of 50 meters meters have to be excava excavated ted.. Both Both the assembl assembly y tunnel tunnel and tail tail tunnel tunnel have have been been excava excavated ted with with the drilli drilling ng and blasti blasting ng method method.. The assem assembly bly and tail tail tunne tunnels ls are excava excavated ted with with headin heading g and benchi benching ng method method.. In this this metho method, d, the tunnel tunnelss are not excavated completely at one go. The tunnel face is divided into heading and benching portions. After that, the excavation of the heading is done and after it proceeds to a certain length, the excavation of the benching portion is done.
This method is very effective when the excavation has to be done with limited resources. This also gives us the example of the type of rock ahead, so that before benching, one can take measures accordingly. accordingly. The assembly tunnel is directed towards the Bhandup end. The measurements of the assembly and tail tunnel at different sections and its progress is taken by the survey department after 1 meter chainage. The overcut and undercut is also recorded by the survey department. After the blasting is done, the tunnel sections are checked for loose rocks and if found they are scaled. The next stage is taking out the muck. Poclains and loaders are placed in the shaft with the help of gantry crane. The poclain and loader collect and put the muck in the muck bucket which is then taken out by the gantry crane. The muck bucet is emptied on the dumping place on the site and after that the muck is dumped at specified dumping grounds.
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Placing of Ribs: Ribs are placed where the tunnel section is weak and there are changes of loose rock debris falling. The ribs are placed over there for support to the section. The ribs are steel structure. The ribs are made on the ground surface and then lowered in the tunnel with the help of gantry cranes.
The space between the ribs and the tunnel section is then filled with concrete. The ribs used till date is made from ISMB200 steel sections and the steel plates used are 3mm thick. The steel used in each and every structure has to be calculated and kept in record for the reconcilation which is used by the Planning department.
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Construction of Retaining Wall: A retaining wall was constructed at site. This retaining wall was constructed because the space available on site was less. This created a need for more space and hence the retaining wall was constructed. Retaining walls are constructed to stabilize slopes or to give support to the ground behind it and not allowing it to move downwards and outwards. The land was thus expanded using rubble and soil and creating a retaining wall in front of it tohold it in place.
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Planning on site: Planning is one of the most important part of any project. Without proper planning, a project can face any number of problems and hurdles. Planning means completing a project within the time, cost and scope of the project. These three parameters a make planning a complete process.
Project Triangle
Planning is the most essential step in project management. Here are a few reasons why planning is important for a project: 1. Happ Happy y cust custom omer ers: s: The main aim of any project is to get happy and satisfied customers. With proper planning, one can get happy customers or clients for each and every project. If clients get happy, then the reputation of the company or firm increases and thus in turn helps the company get more projects. 2. Achiev Achieveme ement nt of of Objec Objectiv tives es:: Planning is also important to know what the objectives or deliverables of a project is. It is also required to know whther they have been achieved or not. 3. Timely imely Compl Completi etion on of the the Project Project:: Time is one of the major factors in the project management triangle and hence has to be always kept in mind. Timely completion completion of projects gives happy clients whch is the end result wanted for every project. 4. Flexib Flexibili ility ty of Projec Project: t: A project may sometime face hurdles in the form of resource availability or some other factor. In these cases, proper planning can avert the time and cost overrun which would be faced otherwise. Thus planning makes a project flexible. It gives alternate paths to complete a project and not be stuck with a single path. 5. Better Better Fina Financi ncial al Perfo Performa rmance nce:: Better planning means better financial performance. 6. More More Prod Produc ucti tivi vity ty:: More productivity means happier workers.
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After the initiation stage, a project is planned to the appropriate level of detail. The main purpose of planning is to plan time, cost and resources adequately to estimate the work needed and to effectively manage risk during project execution. A failure to adequately plan a project greatly reduces the project's chances of successfully accomplishing the goals. Project planning generally consists of 1. Determini Determining ng how to plan plan (e.g. By level level of detail detail or rollin rolling g wave) 2. Develo Developin ping g the scope scope state statemen mentt 3. Select Selecting ing the planni planning ng tea team m 4. Identifyi Identifying ng the deliverab deliverables les and creating creating the the work breakdown breakdown structu structure re 5. Identifying the activities activities needed to to complete complete those deliverables and networking networking the activities in their logical order 6. Estimati Estimating ng the resourc resourcee requirement requirementss for the activi activities ties 7. Estimati Estimating ng the time and cost cost for for the activiti activities es 8. Deve Develo lopi ping ng the the sched schedul ulee 9. Deve Develo lopi ping ng the the bud budge gett 10. Risk planning planning 11. Gaining formal approval approval to begin work Additiona Additionall processes processes such as planning planning for communica communication tionss and scope scope management management,, identifying roles and responsibilities, determining what to purchase and holding a kickoff meeting are generally advisable. For new product development projects, conceptual design of the operation of the final product may be performed concurrent with the project planning activities, and may help to inform the planning team when identifying deliverables and planning activities. Once the project is in the execution stage, the main role of the planning engineer is to monitor and control the progress of the project. Monitoring the project means to check the daily achievement of progress to the progress planned. This is done by updating the progress in the Microsoft Project using the Update Task tool. The progress is checked with the baseline which was approved when the plan was approved. If there are any disc discre repa panc ncie iess or prob proble lems ms with with reso resour urce ce avai availa labi bili lity ty,, the the plan plan can can be chan change ged d accordingly. That is why a plan should be flexible. The daily cash flow is also checked wih the original stipulated cash flow. All these data are collected in the form of Daily Progress Report (DPR). The DPR of each day is then consolidated and a monthly report report is made. This monthly report report is called the Monthly Progress Report. Similarly there are Quarterly Progress Report and Annual Progress Report. Another major document in monitoring and controlling of the project is the Daily Labour Report. This report gives the summary of the number of labors and the number of hours they have worked. This makes it easier to pay the labors and also update the cash flow accordingly. Reconcilation: Reconc Reconcila ilatio tion n is veryi veryimpo mporta rtant nt planni planning ng activi activity ty on site site during during execut execution ion stage stage.. Reconcilation gives an idea on the stock which is available on site or in the stores. This also makes it possible to know the amount of the stock that has already been used in the
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constr construct uction ion activ activiti ities es.. For insta instance nce,, the amount amount of steel steel is known known when when it is first first delivered. But after using it to make different structures, it becomes necessary to know the amount of steel left. This is done by precise calculation of the weight of the steel used. Similarly it is done for other materials too, like, shotcrete material, cement bags, etc. The amount of scrap generated is also calculated so that the amount of steel used is accurate and all the wastage is also accounted for.
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Safety: Safety on site is the most important aspect of a project. Without safety equipments equipments no one is safe on the site. Every body is issued Personal Protective Equipments. These include helmets, safety shoes, nose masks, reflective jackets.
Protective Helmets
Reflective Jackets
There are other safety equipments according to the class of worker one falls in. For example, riggers get safety hooks and gloves. Every member on the site has to go through a process called Safety Induction. In this safety induction they are told about the do's and dont's on the site. They are told about the proper use of their safety equipments, on how to use them and what they are supposed to do during an emergency. All the equipments are issued by the name of the individual and a proper record of these equipments are kept in a record-book with the Stores department. An assembly point is defined, which is a safe place to gather during an emergency. emergency. Every body is issued a role they have to play during an emergency. People are grouped in different groups according to the role they have to play. This is absolutely essential as otherwise there would be a confusion. Confusion is the last thing needed during an emergency. There are groups like the evacuation group, the fire fighting froup, the head count group, etc. Proper areas are marked as smoking or no smoking areas. Every explosive materials are kept in specified spots and are locked when not in use. The Safety department is also responsible for the ERP or Emergency Rescue Plan. This is the procedure to be followed when ever there is an emergency. The plan also includes the proper positioning of fire extinguishers so that it is within the reach of every individual. Fire extinguishers are classified according to the type of fire they help put out. Generally they are classified as type A,B,C or D. However now-a-days fire extinguishers also come in type ABC, which puts out fire of all the type A, B and C. This is the main type of extinguisher used in this project.
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The fire extinguishers are checked periodically to see whether the required pressure is maintained in the can otherwise the squeeze of the extinguisher is reduced which can cause a hazard during fire fighting. Proper alarm installation is also taken care of by the safety department. Intercom facility also lies in the ERP. Intercom is the main method of commun communica icatio tion n betwee between n peopl peoplee of differ different ent depart departmen ments. ts. Emer Emergen gency cy number numberss are installed over each telephone set so that the right people can be contacted when needed. This list includes the phone numbers of the Police, the Firefighting Department, the Hospital, Ambulances, Ambulances, etc. The euipments used on site is also checked periodically by 3 rd parties to see whether they are in working condition or not. As most of the work on this project is done by cranes, the shackles, wire ropes and other tools are checked every six months and are certified to be capable of taking the amount of load it was meant to take. Another safety measurement taken is that every vehicle that comes in or goes out of the site have to submit a copy of their Licences, R.C papers, PUC paers and also have to give details regarding where they are coming from or where they are going to. This way all the vehicles can be tracked and in case of any accident or emergency the whereabouts of the vehicle will be known. HIRA or Hazard Identification and Risk Analysis is an important process done by the Safety department with all the other departments to identify the hazards and risk that might crop out during the period of the project. This meeting also discusses on how to overcome these risks and hazards. All the places where the work is going on is cordoned off with help of barriers. The barrication type depends on the type of the project going on. For instance if it is a road project, then the barrication used is G I sheets, in cases of building projects wooden rails are used, in this project barrier tapes are used. The safety department also keeps a record of the explosive materials going in the tunnel and the number of explosives returned returned along with the LDD (long delay detonators).
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After a period of 1 hour to 1 hour 30 minutes, a safety personnel goes down in the shaft with a gas detector to check whether the conditions were ideal to work in.
Mine Safety Appliances Co. Multi Gas Detector
The otpimal levels safe for working conditions are: 1. O2 : 29.5 to 20.8 2. H2S: 50 ppm 3. CO: 10 ppm
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Conclusion: In conclusion, I would like to emphasise the fact that a rpoject is successful when all the different departments work together. All the departments are like a cog wheel in a machine. Separately they are useles, but when used together they make a very useful machine. In this particular project, I can say it sets a wonderful example of the above thought and I sincerely wish this project a successful end!
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