Group Assignment:IBS System


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Group Assignment:IBS System

  1. 1. 1
  2. 2. 2 Summary Industrialised building system is usually negative develop in Malaysia. Therefore, this research is carried out to find out the reasons and investigate on the usage of IBS system. Through reading this report, readers can understand more about the usage of IBS system and also the benefits of it. This is also to increase the usage of IBS system in Malaysia as we believe that the world keeps on revolving and technology will be always updating.
  3. 3. 3 List of Figures Figure No. Page No. 1. Icon city, PJ (composite method) 2 2. Tunnel Formwork 4 3. Cells for tunnel formwork construction 5 4. Design- Tunnel form construction 7 5. Design – Cellular building 7 6. Safety- working platforms 7 7. Aluminium Formwork 8 8. Components of Aluminium Formwork System 9 9. Smooth finishing surface 10 10. Aluminium Formwork Project Cycle 12 11. Aluminium Formwork braced 14 12. Wall Frame 16 13. Portal Frame 17 14. Skeletal Frame 17 15. Vehicular Hazards 21 16. Falling Hazards 21 17. Fire Hazards 21 18. Machinery & Electrical Hazards 21 19. Fixed Guards 22 20. Fixed Guards 22 21. Tower Crane 23 22. Lifting Hooks 23 List of Tables Table No. Page No. 1. AdvantagesandDisadvantagesof IndustrializedBuilding System 3 2. BuildingSystemComparison 15
  4. 4. 4 Table of Content Content Page Summary i List of Figures and Tables ii Table of Content iii 1.0 Introductionof Industrialized Building System 1.1 Tunnel Formwork System 1.1.1 Introduction of Tunnel Formwork 1.1.2 What is modern method of construction (MMC)? 1.1.3 The Construction Process of the Tunnel Formwork 1.1.4 The Benefits of Tunnel Formwork Construction 1.2 Aluminium Formwork System 1.2.1 Introduction of Aluminium Formwork 1.2.2 History of Aluminium Formwork System 1.2.3 Necessity of Aluminium Formwork System 1.2.4 Assembly of Aluminium Formwork System 1.2.5 Aluminium Formwork – Project Cycle 1.2.6 Benefits of Aluminium Formwork 1.2.7 Disadvantages of Aluminium Formwork 1.2.8 Appropriate Usage by 1-15 2.0 Precast Concrete Installation 2.1 Introduction 2.3 Benefits of Precast Concrete 2.4 Installation of Precast Concrete 2.2 Types of precast concrete structures 16-19 3.0 Safety Precautions in IBS Installation 3.1 Health and Safety 3.2 Training 3.3 Hazards 3.4 Safe Lifting 20-23 Conclusion 24 References 25
  5. 5. 5 1.0 Introduction of Industrialized Building System (IBS) The Vision 2020 emphasizes on the development of the Malaysia’s society in all aspects of life. The purpose of this is to build a united Malaysia nation with a society with strong moral values and ethical values. Therefore, the Malaysia Government created The National Housing Policy to ensure all Malaysian a quality lifestyle. This policy helps Malaysians, especially those who have low income to have adequate and proper shelter and facilities. As the development of Malaysia improved, the economic growth has created a higher demand in construction activities especially the housing industry. So to cater the consumer’s need, the developer of the housing industry needs to adopt a modern technology to cope with this situation without sacrificing the economies of scale. Hence, the Industrialised Building System was introduced. Industrialised Building System (IBS) is a term which is only used in Malaysia by mean of a construction technique which the manufacturing of the structural components in a factory or supervised environment, both off site or on the site, then transported, placed and assembled into construction works. IBS is also known as precast or prefabricated construction, Modern Method of Construction (MMC) and Off-site Construction. Construction Industry Development Board (CIDB) Malaysia promotes the usage of IBS because it will increase the quality and productivity of construction through various training, promotion programmes and incentives. The terms and classifications provided by the CIDB were also misinterpreted as a system limited only for construction of buildings, while IBS can be also interpreted as an approach or process which allows the construction less labour- oriented and faster as well as fulfilling quality concern. The government has made it compulsory for all government projects to contain 70% of IBS system in the construction work. In Malaysia, there are about 5 main IBS groups: Pre-cast concrete frames, panels, and box systems – columns, beams, slabs… Steel formwork systems - permanent steel formworks, tunnel forms … Steel frame systems - roof trusses, portal frame… Prefabricated timber framing systems – timber frames, roof trusses… Block work systems - lightweight concrete blocks and so on...
  6. 6. 6 Figure 1: Icon city, PJ (composite method) The construction methods are generally classified into 4 categories: a. Conventional construction method Components prefabricated on site through timber/plywood formwork installation, steel reinforcement, ready-mix/cast-in-situ concrete (more costly, low speed construction time) b. Cast-in-situ method (non-conventional) It is applicable to all types of buildings. The steel/fibreglass/aluminium formwork acts as a mould and wet concrete is poured into the mould with steel reinforcement places inside it. Its aim is to eliminate traditional timber framed formwork. (Less cost, speedy construction) c. Composite method (non-conventional) The components of the building are partially prefabricated. (Quality improved, shorter construction time, reduce cost) d. Fully prefabricated method (non-conventional) All elements of the building are prefabricated in the factory. (Shortest construction time, high cost) The conventional construction method is currently proved to be the best selection in Malaysia’s construction industry because it is the most cost saving and realistic choice. HOWEVER, studies had been carried out about more on IBS system as we believe that it will take a big role in the future’s construction industry.
  7. 7. 7 Table 1: Advantages and Disadvantages of Industrialized Building System Advantages Disadvantages Cost saving (long run) The formwork of IBS components are mostly made of materials that can be used repetitively (ie: steel or aluminium) and this reduces the construction cost. High initial cost The initial cost to invest in the IBS construction is higher as it requires specified machine to cast the components. Shorter construction time IBS speeds up the construction process because it requires less construction time as the casting of precast element is done at factory only the erection of components are done at site. Requires highly skilled workers Although the numbers of workers is reduced, the quality of workers should be maintained in a good range. IBS system is easy to assemble yet very risky to do so if the workers are not properly trained. Reduction of unskilled workers The use of IBS reduces the construction process at site and consequently reduce the number of labour required on site. Prefabricated elements are inflexible After the elements are constructed, the shape is hardly able to be changed as it is built with high strength Better site environment and construction site cleanliness IBS system reduces the wastage on site as the usage of formwork and tools has been reduced. Transportation inflexibility Large IBS components might be a problem to transport from one place to another and this will increase the construction cost and time. High quality and aesthetic value The quality of the IBS components has its certain standard because it is prefabricated in a strict environment and has good aesthetic value too as it is cast using steel formwork and this creates a smooth surface. Limited Supply IBS system is not that famous in Malaysia’s construction industry yet because not many manufacturers are available. Construction operation not affected by weather The construction process will not be affected by the weather because most of the construction operation of IBS is done in factory. Job opportunity decreases This is due to the demand for labour has decreased which leads to lesser job opportunities available in the market.
  8. 8. 8 1.1 TunnelForm Concrete System Figure 2: Tunnel Formwork 1.1.1 Introduction of Tunnel Formwork Tunnel form is a formwork system that allows the contractor to cast walls and slabs in one operation in a daily cycle. A tunnel formwork of the type comprising a horizontal formwork portion and two vertical formwork portions both of which are resistant to bending. It has become one of the most common methods of cellular construction. This is because it combines the quality, speed and accuracy of factory production with the flexibility and economy of in-situ construction and it is recognized as a modern method of construction (MMC). 1.1.2 What is modern method of construction (MMC)? “A construction process that can encompass the use of composite new and traditional materials and components often with extensive factory produced sub- assembly sections and components. This may be in combination with accelerated on-site assembly methods and often to the exclusion of many of the construction industry traditional trades. The process includes new buildings and retrofitting, repair and extension of existing buildings.” (Zurich, 2014) This is whereby the concrete industry offers concrete solutions which can be used to reduce construction time and promote sustainable development, as well as offering cost savings to embrace the innovation and modern methods of construction (MMC).
  9. 9. 9 Figure 3: Cells for tunnel formwork construction 1.1.3 The Construction Process of the Tunnel Formwork Tunnel formwork construction is a process of creating a structural tunnel by pouring concrete into the steel formwork to form the slabs and the walls. The formwork is moved every 24 hours so that another tunnel can be formed. After a storey has been completed, the process is repeated on the next floor. It creates cells which can be easily subdivided into rooms. Tunnel forms can be extended using a mid-span section if longer spans are required. Walls can be designed as deep beams and supported at low level on columns to enable car parking. The result of this tunnel formwork construction is a cellular reinforced structure will be formed whereby the surfaces are sufficiently high quality which only requires minimal finishing for direct decoration. The end walls and facades can also be easily completed with thermally insulated units which can be clad as required. This system creates an efficient load- bearing structure for use in a wide variety of applications. It is particularly effective in projects suited to repetitive cellular construction such as residential condos or apartments, hotels, hostels, barracks and prisons.
  10. 10. 10 1.1.4 The Benefits of Tunnel Formwork Construction The Malaysian construction industry is rapidly immersing the tunnel formwork system in the construction process. The construction industry has been encouraged by the government to adopt this IBS system because it enables the project to be completed economically, efficiently and faster with benefits for everyone concerned. a. Costs It is able to provide cost-effective and high quality construction. The system is currently one of the most preferred methods of cellular construction with engineers, architects and contractors throughout the world as it has the ability to deliver projects on time and to budget. b. Ease of Service Installation Service runs can be pre-installed before the concrete is poured. Other facilities such as bathroom pods can be installed as complete units using existing access platforms. c. Quality Quality is enhanced despite the speed of construction. The precise, even steel face of the formwork creates a smooth, high quality finish capable of receiving direct decoration with the minimum of preparation (a skim coat may be required). This reduces the requirement for following trades, thus providing additional cost savings and speeding the entire process. d. Design The usage of tunnel form to large bays constructed provides an exceptional flexibility in the layout and design of the building and allows a high degree of freedom in the final look. (ex: Extendable formwork can be used to create cantilevered balconies and the exterior can be finished according to the architect’s requirement, from brick slips on high insulated framed infill panels, to sophisticated curtain wall systems.)
  11. 11. 11 Figure 4: Design- Tunnel form construction Figure 5: Design – Cellular building e. Safety The construction of tunnel form must require integral working platforms and edge protection systems. In addition, training must be completed by each and every labour. Minimize the requirement of tools and equipment when moving the tunnel form to further reduces the risk of accidents. Figure 6: Safety- working platforms f. Sustainability The local availability of ready-mixed concrete supplies and cast-in-situ of units reduces the transportation impacts. Nearly zero wastage is produced with associated safety and cost savings benefits. The heating costs can be minimized by coupling the concrete’s thermal mass with correct insulation and boiler design which can even reduce air-conditioning requirements
  12. 12. 12 1.2 Aluminium FormworkSystem Figure 7: Aluminium Formwork 1.2.1 Introduction of Aluminium Formwork Aluminium Formwork System is a construction system for forming cast in place concrete structure of a Building. Aluminium Formwork System provides aluminium formwork for multi-storeys, load-bearing buildings and enables the walls and slab to be poured in one operation. This leads to the increasing of construction efficiency and also to produces a strong structure with excellent aesthetic value. The consistency of the concrete finishes and shapes can be obtained accurately due to the fine tolerances of the machined metal formwork. It confirms to produce the most exact standards of accuracy and quality and also to allow plumbing and electrical fittings to be prefixed with the certain knowledge that there will be an exact fit when assembled. The accuracy at the concreted work results in consistent fittings of doors and windows. Furthermore, the smooth finishing surface of the concrete eliminates the need for additional plastering. The Aluminium Formwork System has been widely used in the construction of residential units or both low-rise and high-rise buildings and has proven to be very successful in the construction of housing projects in the world. It is also a system
  13. 13. 13 which schedules and controls the work of other connected construction trades such as concrete placement, steel reinforcement and mechanical, electrical inserts. 1.2.2 History of Aluminium Formwork System In the late 1970’s, W.J. Malone, a Canadian Engineer as a system for constructing low-cost housing units in the developing countries, developed the Aluminium Formwork System. The units were casted in place with concrete to the load-bearing walls and formed with aluminium panels. To enable it to be erected by the hundreds, it uses a repetitive design; the system ensured a fast and economical method of construction. 1200 units were built in Egypt by using that fundamental concept followed by 1500 units in Iraq. The latter project sets a record for its speed and quality of construction at minimal cost as it was incredibly successful- Then, Aluminium Formwork System has been used successful in different countries like Hong Kong, Egypt, India, Indonesia, Malaysia, Iraq, Philippines, Singapore, South Korea, Taiwan and Thailand. Figure 8: Components of Aluminium Formwork System
  14. 14. 14 1.2.3 Necessity of Aluminium Formwork System The disparity between the supply and demand for affordable housing is tremendous. The rapid urbanization in our generation has resulted in a geometric increase in the housing demand, which cannot be fulfilled by using the conventional methods of construction. Comparatively, the traditional /conventional method of construction for mass housing is too slow and has limited quality control, particularly when a large scale project is involved. Therefore, it is obligatory to work out a method or a scheme where the quality and speed of construction are controlled by a systematic approach automatically. Aluminium Formwork System is adoptable for any design of a building and it establishes a kind of assembly line production. The methodology of using Aluminium Formwork System takes in to consideration the important parameters namely the no. of housing units and the time that is available and works out the component of input as formwork. The whole structure is constructed with load-bearing walls cast-in-situ by using pre-engineered aluminium forms with form-finished concrete and no plaster on any face. Figure 9: Smooth finishing surface
  15. 15. 15 1.2.4 Assembly of Aluminium Formwork System The simplicity of Aluminium Formwork and the repetitive nature of the assembly process make it possible to accurately programme construction sequences and thus cycle times well in advance. In addition, this enables the unskilled labour to work with the formwork and reduces the burden on skilled labour when this is in short supply. Before leaving the factory, all panels are clearly labelled to ensure that they are easily identifiable on site and can be smoothly fitted together using the formwork modulation drawings.  PIN AND WEDGE SYSTEM o A simple pin and wedge system passes through holes in the outside rib of each panel and held the panels in position.  QUICK STRIP PROP HEAD o One of the principal technical features which enables this speed to be attained using a single set of formwork panels is the unique V shaped prop head which allows the 'quick strip' to take place whilst leaving the propping undisturbed. The deck panels can therefore be reused immediately.
  16. 16. 16 1.2.5 Aluminium Formwork – Project Cycle Figure 10: Aluminium Formwork Project Cycle
  17. 17. 17 1.2.6 Benefits of Aluminium Formwork The in-situ construction of all partitions and walls reduces the requirement for follow-on wet trades. The surface finish produced with the aluminium forms allows achievement of a high quality wall finish. Doors and windows are formed in position, with this high degree of precision items such as door and window frames can be directly installed on site with minimal re-sizing required. a. Speed The in-situ construction of all walls and partitions reduces the requirement for follow- on wet trades. Doors and windows are formed in position, with this high degree of precision items such as door and window frames can be directly installed on site with minimal re-sizing required. b. Quality Aluminium Formwork panels ensure consistency of dimensions. A high quality concrete finish is produced to accurate tolerances and verticality on the removal of the formwork mould, The natural density of the concrete wall also result in better sound transmission c. High Aesthetic Value The concrete surface finish produced by the aluminium forms allows achievement of a high quality wall finish without the need for extensive plastering. Typically only a 3mm to 4mm skim coat is applied internally prior to finishing and a 6 mm build up coat prior to laying tiles. d. Durability The durability of a complete concrete structure is more than conventional brick bat masonry. e. Negligible Maintenance Strong built up of concrete needs no maintenance.
  18. 18. 18 1.2.7 Disadvantages of Aluminium Formwork a. Initial high cost investment. b. Compares very poorly on modifications, against brick work constructions. c. Fear of theft of valuable Aluminium Extrusions & sheets & hence kit not being complete at critical stages of construction. d. Mass Housing projects are not as high for investing in large number of Aluminium Formwork. 1.2.8 Appropriate Usage by:  Mass housing with repetitive design.  Redevelopment projects.  Specialized contractor. Figure 11: Aluminium Formwork braced
  19. 19. 19 Source:Duralite productpresentation Table 2: Building System Comparison
  20. 20. 20 2.0 Precast Concrete Installation 2.1 Introduction Precast concrete is widely used in the construction industry nowadays due to the advantages that it can bring not only to the contractors, but also to the client and the building itself. Precast concrete is ‘pre-casted’ or fabricated in a factory or a controlled environment and then transport to the site to be erected. The precast concrete does not necessarily have to be casted in a factory; it can be casted at the site also. The concrete is pour into a metal mold with the reinforcement and is cured and taken out after the concrete has set. It is then transported to the site and erected with the help of a lifting system such as crane. 2.2 Types of precast concrete structures Figure 12: Wall Frame This type of precast structure involves only the wall and floor on the building only. It does not include of the beam or column or other elements of a building.
  21. 21. 21 Figure 13: Portal Frame Portal Frame structure is normally used in buildings such as warehouses or factory. It consists only of the roof and rafters and also column. Figure 14: Skeletal Frame This is a skeletal frame structure which consists of beams, floor slabs and columns.
  22. 22. 22 2.3 Benefits of Precast Concrete Strength and durability The strength of precast concrete will increase over time and it will not deteriorate easily. It can withstand a heavy load as the concrete is reinforced with high tensile bars. Quality The precast concrete is fabricated in a controlled environment in a factory. This can ensure that the products are of high quality and consistency. Aesthetics Value The appearance of a precast concrete product can be selected or changed to suit the preference of the client or to blend in with the existing building in the neighbor. The precast concrete provides different colors, textures and finishes. Time saving Precast concrete are fabricated in factory beforehand and move to the site when it is ready to be installed. Its progress will not be affected by the weather unlike cast in situ concrete. Economic With precast concrete, the total time of construction can be reduced which in turn saves cost. It also reduces wastage that are produced by cast in situ concrete that makes use of timber formwork. Precast concrete make use of metal mold which can be used over and over again.
  23. 23. 23 2.4 Installation of Precast Concrete Planning Planning is important in the installation of precast concrete. Firstly, the time of the delivery and transportation of the product should be planned so that when products are delivered to the site, it can be installed immediately without having to leave the large pieces of products at the site that can cause disruption or obstruction at the site. The sequence of delivery is important too and this will allow construction progress to run smoothly without any delays. A checklist can be made to make sure the conditions and requirements are met. Deliveryto site The precast concrete should be delivered to the site where it can be directly erected after reaching the site. The schedule and sequence of the parts should be decided to minimize confusion and delay. The route of the delivery should be examined before delivering as sometimes the size of the precast concrete can be very big and the size of the road and traffic on the road can affect the delivery. During transportation, the parts should be secured so that it does not fall of the truck or get damaged. The truck should be able to access to the site with enough space and the ground condition of the site must be check to avoid any difficulties in transporting and unloading.
  24. 24. 24 3.0 Safety Precautions in Pre-cast Installation 3.1 Health and Safety Employers have a responsibility to ensure the health and safety of all employees in the work environment. Including themselves, they must also ensure that their actions do not harm any other person while at work. They must provide and maintain a safe working environment. Some examples are by providing and maintaining facilities, machinery, and equipment. Employees must be protected from hazards and should learn how to deal with emergencies that could arise. Employees must also be well informed before the commencement of a project. Information such as emergency procedures, hazards that are associated and how to manage the hazards, location and correct use of the safety equipment should be taught to the employees. 3.2 Training It is sometimes taken lightly by employees of the construction industry whereby accidents can happen which, in the worst case scenario, can lead to death. Therefore, the main concern is the safety of the employees in the construction site. In order to ensure a safe work place for the employees, they must be trained and instructed in safe systems of work and safe work practices. Employers must first ensure that an appropriate experienced person will be able to supervise employees who are not yet sufficiently skilled and experienced to carry out their work safely. Training programs are the ways to help employees improve their knowledge and skills. Education and training programs include first aid training minimum requirements, identification of hazards and the selection, care and use of protective equipment. 3.3 Hazards The production of pre-cast concrete components consists of production processes such as casting, finishing, storage, and transporting. As these processes are being made, there can be hazards which could arise. A hazard is an existing, new or potential situation or event that could jeopardize the safe and healthy working environment.
  25. 25. 25 Common Hazards:-  Hazards associated with material handling of pre-cast concrete components.  Hazards associated with storage of pre-cast concrete components.  Vehicular hazards.  Machinery & electrical hazards.  Falling hazards.  Noise.  Piercing hazards due to protruding rebars.  Fire hazards.  Chemical hazards. Figure 16: Falling HazardsFigure 15: Vehicular Hazards Figure 17: Fire Hazards Figure 18: Machinery & Electrical Hazards
  26. 26. 26 3.4 Safe Lifting Safe lifting is important because moving machineries can cause injuries in many ways. Some examples are :-  Workers in the construction site can be hit or injured by moving parts of machinery.  Sharp edges can cause cuts and severing injuries.  People can be crushed between parts moving in together.  Poor or no maintenance of equipment can develop faults.  Parts of equipment may fail or loads may drop. To ensure that the equipment is fully functional and hazard-free, make sure that the equipment is safe for any work. Make sure that it is installed properly, is stable and is not in a location where other workers may be exposed to risk. Choose the right equipment for the appropriate job. Appropriate measures such as using fixed guards to enclose the dangerous parts can reduce risk and provide more protection. Fixed guards can be of secured screws or nuts and bolts. There are also other methods such as interlocking the guards so that the equipment cannot be started before the guard is closed and cannot be opened while the machine is still moving. As some pre-cast components can be very large, cranes are used to lift these components to put them in the desired place. There are a few types of cranes such as tower cranes, mobile cranes, and crawler cranes. Lifting hooks are installed at the top of the components and lifted by the tower cranes through the hooks. There should be a lifting plan supported by risk assessment. To eliminate hazards or reduce risks, the lifting operation should be categorized with its risk level Figure 19: Fixed Guards Figure 20: Fixed Guards
  27. 27. 27 and complexity so that suitable controls can be applied. A good lifting plan leads to less risk which means it may also lead to less cost due to faults or accidents. It also reduces the time to install the pre-cast components, speeding up the construction process. Figure 21: Tower Cranes Figure 22: Lifting hooks
  28. 28. 28 Conclusion In a nutshell, IBS should be seen as an innovative improvement in the construction industry. In industrialized construction, this innovation agenda has been promoted worldwide. It is imperative that IBS is seen as an evolution of construction using new and innovative techniques rather than a revolution. The classification of IBS should be expanded to cater the scope of volumetric (modular) and hybrid construction. IBS is not to be seen as a threat to traditional methods. Both methods should be able to work in tandem and improve their processes collectively. The usage of both method constructions is important to ensure that the construction industry will obtain the best benefits from both systems. IBS should move up the degree of industrialization from prefabrication to reproduction through innovation. The mass-customisation concept which is vital to open building system agenda can only be achieved through the adoption of automation in the level of industrialization The more advanced IBS is in the level of industrialization, IBS need to play more roles and has to be involved in project life cycle. The reproduction level of industrialization will involve the whole project life cycle from planning to maintenance. IBS can be seen as a solution to the whole project life cycle if only, it can achieve reproduction level of industrialization It is hoped that the generic definition and classification that had been proposed in this paper will initiate positive debate into it and obtain constructive reaction from practitioners and researchers hoped, and thus will enhance our understanding of IBS.
  29. 29. 29 References 1. Anon, (2014). 1st ed. [ebook] Available at: [Accessed 8 Jun. 2014]. 2. Anon, (2014). 1st ed. [ebook] Available at: [Accessed 14 Jun. 2014]. 3. Anon, (2014). 1st ed. [ebook] Available at: health/Safety%20and%20Health%20at%20Pre-cast%20Yards.pdf [Accessed 29 May. 2014]. 4. Anon, (2014). 1st ed. [ebook] Available at: [Accessed 11 Jun. 2014]. 5. Anon, (n.d.). 1st ed. [ebook] WSHCouncil. Available at: _Safe_Operation_of_Lifting_Equipment.pdf [Accessed 23 Jun. 2014]. 6., (2014). Tunnel form. [online] Available at: earing_walls/tunnel_form.aspx [Accessed 9 Jun. 2014]. 7. Manaf, N. (2014). Product Presentation | Duralite (M) Sdn Bhd. [online] Available at: [Accessed 1 Jul. 2014]. 8. Modern methods of construction (MMC). (2014). 1st ed. [ebook] Zurich. Available at: Insight-Modern-Methods-of-Construction.pdf [Accessed 8 May. 2014]. 9., (2014). RSB Formwork Technology: Products. [online] Available at: [Accessed 22 Jun. 2014]. 10. The National Precast Concrete Association, (2006). THE LITTLE BOOK OF CONCRETE. [online] Available at: content/uploads/docs/100_Adantages_of_Precast_Concrete.pdf., (2014). Self Reacting Tunnel Formwork. [online] Available at: system.html [Accessed 25 Jun. 2014].