Journal articles: 'Concrete construction formwork'

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Taher Ahmed, Mohammed, Rozana Zakaria, Mohamad Zin Abd Majid, and Ismail Mohd Affendi. "Importance of Sustainable Concrete Formwork System." Advanced Materials Research 598 (November 2012): 360–65. http://dx.doi.org/10.4028/www.scientific.net/amr.598.360.

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Construction industry is seen to be able to play a bigger role into a sustainable society by offering sustainable construction. As the premier construction material across the world, concrete has a major determining role on the effects, good or bad, of construction on the environment, meanwhile the formwork system is one of the important construction methods in building construction, which eventually will lead to more sustainable construction. In this context, this study focuses on the importance of the formwork system and its influence on achieving sustainable construction. The study aims to identify the basic sustainability objectives that considered responsive to formwork system. Using questionnaire survey distributed among construction experts, the economic category had been selected as the most important factor that considered respond to the formwork system, and the environmental category comes second while social comes the third. Furthermore, fifty percent of the respondents agree that type of formwork system effect on the sustainability of the construction project and about forty percent was moderate about it. Determination the objectives of sustainability that respond to the formwork system, which covers all activities and processes related to the formwork system can assist developers and others stakeholders to evaluate the performance of the system in order to make enhancement to the system.

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Jipa, Andrei, Mathias Bernhard, Nicolas Ruffray, Timothy Wangler, Robert Flatt, and Benjamin Dillenburger. "Formwork fabrication freedom for a concrete canoe." Gestão & Tecnologia de Projetos 14, no. 1 (September 6, 2019): 25–44. http://dx.doi.org/10.11606/gtp.v14i1.148264.

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The pursuit for complex geometries in contemporary architecture is driving innovation towards an unconstrained fabrication freedom for building components. Concrete is a building material with excellent structural and architectural qualities, which has the theoretical capacity of being cast into any shape. However, in practice, concrete is generally limited by the formwork manufacturing industry to simple, planar shapes. To overcome this fabrication limitation, this research investigates the use of large-scale 3D-printed plastic formworks for concrete components. This novel construction method takes advantage of the load-bearing capacity of concrete and relies on the fabrication-freedom inherited from the 3D printed formwork, thus making complex topologies and precise details possible for concrete structures. To demonstrate the potential applications of this method, skelETHon —a functional four-meter-long concrete canoe— was designed, built and raced in a regatta on the Rhine river. The research focused on the optimization of the 3D printing process for large-scale plastic formworks and on improving the stability of the thin formwork shells during casting.

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Ahmad, Nursafarina, Zakiah Ahmad, Azerai Ali Rahman, Hanizah Abdul Hamid, and Mohd Azrizal Aziz Fauzi. "Increasing the Capacity of Concrete Column with Integrated Permanent Formwork Using Wood-Wool Cement Board." Applied Mechanics and Materials 325-326 (June 2013): 1305–9. http://dx.doi.org/10.4028/www.scientific.net/amm.325-326.1305.

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Growing construction activities requires increase in construction materials. The conventional method of constructions results in a rise in construction waste. Formwork as a main factor to generate construction waste has been the topic of investigation. The permanent formwork has been introduced with the aim to: promote the construction technology process that put quality, safety and environment issues into account, reduce the cost of workers and reduce the overall time of construction project. At present the permanent formwork available in the market are made from steel, and plastic and the cost is still high. Therefore this study is looking at the potential of commercial wood-wool cement board (WWCB) as permanent formwork. A series of concrete columns were constructed with and without integrated WWCB with different configurations of WWCB as permanent formwork. These columns were subjected to axial load and the compressive strength and failure modes were recorded. The results show that the present of permanent formwork from WWCB improves the compressive strength of the column. With the permanent formwork, the size of concrete column can be reduced and able to support the same load as column without permanent formwork. Therefore this construction method can reduce the overall cost of construction.

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Li, Jian Ping, Pin Tan, Jin Huang, and Xiang Jun Wang. "Simulation and Experimental Study of Floating with Engineering Mechanics on Box Girder Steel Interior Formwork Used in the High Speed Railway." Applied Mechanics and Materials 540 (April 2014): 185–88. http://dx.doi.org/10.4028/www.scientific.net/amm.540.185.

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During the construction of high speed railway box girder, the interior formwork’s floating problem is always been a big common quality fault plagued the construction in the process of concrete pouring, this leads to the roof thickness of box girder arising, the harm is great. This paper combined the construction project of Hebang single linear 32 meter interior formwork, according to the actual condition of the construction, proceeding the simulation analysis and experimental study of floating date on box girder interior formwork. Using the solidworks2010 establish the mode of box girder interior formwork, then, import the mode to the workbench14.5 proceeding simulation analysis. The simulation analysis of interior formwork maximal floating date is 10.67 millimeter, while the measured date is 10.63 millimeter, the deviation is 3.2%. The result manifests the feasibility of the simulation analysis of interior formwork floating date, this provide a reference to the structure optimization of the interior formwork used in the high speed railway.

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Taher Ahmed, Mohammed, Rozana Zakaria, Rosli Mohamad Zin, and Rania Hussien Ahmed. "Sustainability Indicators for Concrete Formwork System." Applied Mechanics and Materials 525 (February 2014): 504–8. http://dx.doi.org/10.4028/www.scientific.net/amm.525.504.

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As the premier construction material across the world, concrete has a major determining role on the effects, good or bad, of construction on the environment, meanwhile the formwork system is one of the important construction methods in building construction, which eventually will lead to more sustainable construction. This study is about the sustainability elements that respond to formwork system and their contribution to the main factors of sustainability using questionnaire survey distributed among construction experts. The economic factor had the most contribution to sustainability performance of formwork system; the environmental factors come second and at final come the social factors. Furthermore, the economic factor had seven elements effect formwork system performance and the environmental factor include six elements while social factor had only three elements.

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Brózda, Kinga, and Jacek Selejdak. "Safety of Formworks in the Engineering and General Construction Sector." System Safety: Human - Technical Facility - Environment 1, no. 1 (March 1, 2019): 284–90. http://dx.doi.org/10.2478/czoto-2019-0037.

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AbstractFormwork systems are necessarily used in the implementation of the RC (reinforced concrete) structures. Formworks are required regardless of whether a construction is monolithic or prefabricated and used to form the engineering and general structures or structural elements, such as abutments, supports and decks of the bridges, tanks and retaining walls, but also industrial and accommodation facilities etc. Ensuring the OHS (occupational health and safety) during transport, assembly and disassembly of formworks is a necessary condition for the execution of RC works in a safe and economical way. The paper presents the analysis of the safety requirements for formworks. Furthermore, the general requirements for the execution of the formwork structures were discussed. The most common organizational and technological mistakes and cased of neglects related to the operation of the formwork which lead to infringement of the OHS regulations were also identified.

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Tang, Qing Rong, and Zhi Qiang Fu. "Time-Varying Law Experimental Research of the Interaction of Concrete Structure and Formwork Support during the Construction Period." Applied Mechanics and Materials 488-489 (January 2014): 466–69. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.466.

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Research for mechanism of concrete structure interacting with formwork support by manufacturing 2 test models of two-layer and single-span reinforced concrete frame at laboratory,and analysis interaction performance between concrete structure and formwork support and the influence of construction period,curing time of concrete and load on mechanical performance of formwork support system during the construction period.Research data shows:formwork support system interacted with concrete structure is a linear system when live load applied is smaller then crack load calculated according to mechanical indicators of loading-age concrete;load applied by formwork support system decreases with develop of curing time of concrete and removal of bottom support and construction period extension;it is also effected by environmental temperature.

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Liang, Yong Duo, Zhi Guo Sun, Jin Zheng Jiang, Gong Cai Chi, and Yue Jiang. "Shear Resistant Strength Analysis of Construction Formwork Concrete Shear Wall." Applied Mechanics and Materials 166-169 (May 2012): 3311–16. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.3311.

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Construction formwork concrete shear wall is one of new type of structural system. In order to study the shear resistant strength of construction formwork concrete shear wall, 21 quasi-static test results were collected, influence factors which affect the shear resistant strength of construction formwork concrete shear wall through grey-correlation analysis method were analyzed. It is found that, among the influence factors, axial compressive force is the most important, secondly is the effective height of the wall, the distance among stiffening ribs in the latitudinal direction show small influence. And the expressions to estimate the shear resistant strength of construction formwork concrete shear wall were proposed by regression analysis method.

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Feng, Qi, Xiao Guang Wu, and Ben Dong Zhao. "Study and Application of Permeability Formwork to Marine Concrete." Applied Mechanics and Materials 438-439 (October 2013): 333–37. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.333.

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During the construction of concrete structure, laying controlled permeability formwork within the traditional formwork can effectively improve the durability of concrete for marine structures and prolong the working life of concrete structures. This paper discusses the working mechanism of controlled permeability formwork, introduces its development history and research status, summarizes the construction process and matters needing attention of controlled permeability formwork, and puts forward the problems remaining to be solved at present.

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Chellappa, Vigneshkumar, and Urmi Ravindra Salve. "Understanding the fall-related safety issues in concrete formwork." E3S Web of Conferences 263 (2021): 02007. http://dx.doi.org/10.1051/e3sconf/202126302007.

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The construction industry recorded high rates of fatalities and injuries due to falls at the workplace. Among other activities, concrete formwork tends to have more fatal falls. This study aims to understand the fall-related safety issues in the formwork lifecycle of construction projects. To achieve this, the process of formwork activities was mapped, and the safety risks associated with each activity were classified. Method development and risk identification focused on interviews with construction professionals involved in the construction of formwork and site observations of the formwork activities. The overall finding was that pouring, stripping, and erection activities have more issues related to falls. Future research is being carried out to assess the risks of falls from the construction experts’ views to prevent fall accidents in the future.

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Ko, Chien-Ho, and Jiun-De Kuo. "MAKING FORMWORK CONSTRUCTION LEAN." Journal of Civil Engineering and Management 21, no. 4 (March 30, 2015): 444–58. http://dx.doi.org/10.3846/13923730.2014.890655.

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Formwork material and payroll are among the greatest costs in building reinforced concrete structures. Therefore, formwork engineering is a key factor affecting project success. Traditional formwork construction entails non-value-adding activities resulting in waste. The objective of this study is to adapt lean manufacturing techniques to formwork engineering in a bid to reduce waste, specifically by developing a lean formwork construction model. In the model, andon is used to establish an on-site quality control culture, allowing form workers to obtain assistance immediately whenever a problem occurs. In addition, formwork operations are pulled through the kanban system to reduce mould inventory and achieve continuous construction flow. A case study is used to validate the applicability of the proposed model. Results show that the proposed model can effectively reduce waste in the formwork construction flow and increase the value of operations, thus providing a new approach to improving formwork engineering.

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BOUHAROUN, Samir. "CHARACTERIZATION OF THE INTERFACE BETWEEN FRESH CONCRETE AND FORMWORK." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 22, no. 1 (December 18, 2015): 26–37. http://dx.doi.org/10.3846/13923730.2014.893912.

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Concrete surface quality is generally linked to the development conditions of concrete close to the formwork. This work aims to study the influence of the nature of release agent and the quantity of fine elements on the chemical interactions at the concrete/oil/formwork interface. Five concretes were prepared at 28, 30, 32, 34, and 36% of paste to study the influence of paste volume on the friction between formwork and fresh concrete. The friction tests were performed using an apparatus which can reproduce the same conditions of construction sites. In addition, a physicochemical investigation was achieved to identify the effect of fine elements on the ability to form the interstitial mediums at the interface. The formation of soap in the vicinity of the formwork surfaces was also studied as a function of the content and the nature of oils. The results showed that the friction between fresh concrete and formwork depends on the pore solution content present at the interface.

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Tian, Guo Liang. "Research on Application of New Concrete Silo Construction Technical System." Advanced Materials Research 1065-1069 (December 2014): 1577–85. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.1577.

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considering the development of concrete silo structure in recent years and engineering characteristics of large reinforced concrete silo, construction processes and structures of concrete silos are classified and general construction technical system is formed through innovation of construction technique and process. The general construction technical system focuses on adjustable drawbar climbing formwork system, inside drawbar-free climbing formwork system and whole lifting and towing integrated climbing formwork system, is featured with integrated construction and has multiple technical units, which could be combined flexibly to adapt to certain requirements of different projects. This method not only has flexible process, but also possesses uniform construction technique and process.

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Li, Yang, and Jian Cai. "Mechanics Analyzing of Suspended Formwork Supporting System and Research of Decision System in Constructing Transfer Storey Structure of Steel Reinforced Concrete." Applied Mechanics and Materials 232 (November 2012): 925–29. http://dx.doi.org/10.4028/www.scientific.net/amm.232.925.

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This article introduced the research of suspended formwork in constructing transfer storey structure of steel reinforced concrete, and the co-working principle of beam and supporting system, and the design theory of suspended formwork method. The author farther founded construction decision system through analytic hierarchy process, and applied in construction site successfully.

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Yuan, Xue Xia, and Wei Liang Jin. "Structural Reliability and Human Error of Reinforced-Concrete Building during Construction." Advanced Materials Research 368-373 (October 2011): 1365–69. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.1365.

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In view of the significant failure modes of formwork-supporting system and reinforced- concrete member, the reliability analysis model of time-dependent system affected by human errors during the construction of typical multistory reinforced-concrete buildings was developed. Human Reliability Analysis (HRA) method was applied to simulate the error rates and error magnitudes of the reinforced-concrete members and the formwork-supporting system, and human reliability models were developed, two cases for error-free case and error-included case were considered. Furthermore the check emphasis of formwork-supporting system was pointed during multistory building construction.

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Kollegger, Johann, Bernd Köberl, Helen Kane, Sebastian Zoran Ambro, Andreas Kainz, and Herbert Pardatscher. "Construction of Reinforced Concrete Shells without Formwork." IABSE Symposium Report 92, no. 11 (January 1, 2006): 1–8. http://dx.doi.org/10.2749/222137806796184932.

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Hamooni, Morteza, Mojtaba Maghrebi, Javad Majrouhi Sardroud, and Sungjin Kim. "Extending BIM Interoperability for Real-Time Concrete Formwork Process Monitoring." Applied Sciences 10, no. 3 (February 6, 2020): 1085. http://dx.doi.org/10.3390/app10031085.

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The concrete formwork process is a critical component of construction project control because failing to gain the necessary concrete strength can lead to reworks and, consequently, project delays and cost overruns during the project’s execution. The goal of this study is to develop a novel method of monitoring the maturity of concrete and providing reduced formwork removal time with the strength ensured in real-time. This method addresses the wireless sensors and building information modeling (BIM) needed to help project management personnel monitor the concrete’s status and efficiently decide on the appropriate formwork removal timing. Previous studies have focused only on the monitoring of concrete’s status using sensor data or planning the formwork layout by integrating the BIM environment into the design process. This study contributes to extending BIM’s interoperability for monitoring concrete’s maturity in real-time during construction, as well as determining the formwork removal time for project control. A case study was conducted at a building construction project to validate the developed framework. It was concluded that BIM can interoperate with the data collected from sensors embedded in concrete, and that this system can reduce formwork removal time while retaining sufficient strength in the concrete, rather than adhering to the removal time given in building code standards.

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Gelbrich, Sandra, Henrik L. Funke, Andreas Ehrlich, and Lothar Kroll. "Flexible fiber-reinforced plastic formworks for the production of curved textile-reinforced concrete." Advances in Structural Engineering 21, no. 4 (October 5, 2017): 580–88. http://dx.doi.org/10.1177/1369433217732681.

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A new constructive and technological approach was developed for the efficient production of large-dimensioned, curved freeform formworks, which allows the manufacturing of single- and double-curved textile-reinforced concrete elements. The approach is based on a flexible, multi-layered formwork system, which consists of glass fiber–reinforced plastic. Using the unusual structural behavior caused by anisotropy, these glass fiber–reinforced plastic formwork elements permit a specific adjustment of defined curvature. The system design of the developed glass fiber–reinforced plastic formwork and the concrete-lightweight-elements with stabilized spacer fabric was examined exhaustively. Prototypical curved freeform surfaces with different curvature radii were designed, numerically computed, and produced. Furthermore, the fabric’s contour accuracy of the fabric was verified, and its integration was adjusted to loads. The developed textile-reinforced concrete had a high three-point bending tensile strength. Beyond that it was ensured that the textile-reinforced concrete had a high durability, which has been shown by the capillary suction of deicing solution and freeze–thaw test with a low amount of scaled material and a relative dynamic E-modulus of 100% after 28 freeze–thaw cycles.

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Wang, Li Jiu, Xin Gu, and Dan Sun. "Concrete Structure System Based on Stay in Place Formwork." Advanced Materials Research 160-162 (November 2010): 550–53. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.550.

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The utilization of stay in place formwork in concrete structure has received considerable attention in recent years. It is comparatively low labor intensity, readily available and has a range of attractive properties and characteristics that makes it suitable for a variety of building and construction applications. The fabrication and seismic behavior was studied in this paper. The experiments have shown that sufficient data have been obtained to give confidence in the reinforcing mechanism of stay in place construction formwork, and future work need only be focused on formwork design and standardization.

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Lin, Lee Kuo, Yueh Ching Wu, and Bing Chen Tseng. "Value Management and Analysis of Plastic Formwork." Advanced Materials Research 773 (September 2013): 455–59. http://dx.doi.org/10.4028/www.scientific.net/amr.773.455.

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The civil and construction industry is the basis of industries, it has always been known as the "leading industry" and in such industry the basic material is reinforced concrete. Even in this 21st century materials science and engineering methods have developed perfectly, reinforced concrete still is the main structure material in civil and construction industry. Formwork activity is one of indispensable matters during concrete forming and hardening processes. Once the forming process has defect, it might cause the formwork collapse during the concrete placing procedure. Such damage will result in pecuniary loss or workers life. This illustrating that the formwork is one of the most important materials in theconstruction industry. In general, formwork is mainly usedtimberas its rawmaterial. Therefore, the wooden formworkwill naturallydestruct and discard after repeating four to six times. But the remaining nail and chemicals treatment on the timber surface of the waste formwork always make the subsequent activity not easily. Such process does not echo todays trend of emphasis on the energy conservation and environmental protection. Besides, in order to keep the progress of the industry, all kinds of civil and construction industries are still continuous without considering the global temperature is getting warmer. But the timber,asaformwork rawmaterial,thespeedof deforestation is far behind the progress of forestation. Timber material will bedeforested somedaywith such vicious cycle. Therefore, if there is any appropriate material to replace wooden formwork, it will be a valuable issue for further research. The subject of this research is using value analysis to compare function and cost between plastic formwork plate and wooden formwork plate. For the study analysis, due to thelife cycleoftheplastic formwork plate andwooden formwork plate are notthe same, so this research developstheconceptoflife cost for doing the performance comparison between plastic formwork and wooden formwork with workability, cost, flat surface and environment. The study result shows the plastic formwork is full with potential to develop.

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Tikhonov, Anatoly Fedorovich. "Automation of Concrete Heat Treatment in Thermoactive Formwork in Monolithic Housing Construction." Applied Mechanics and Materials 897 (April 2020): 250–54. http://dx.doi.org/10.4028/www.scientific.net/amm.897.250.

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The block diagram and algorithm for concrete treating in thermoactive formwork is presented. Article presents parameters of the concrete mix, to enter in a command block before automated heating of the concrete mix in thermoactive formwork in accordance with the schedule of changes in concrete temperature in the process of obtaining desired strength. Article formulates mathematical model of the control object for thermal treatment of concrete with consideration of the specifics and general patterns, processes and technological requirements. Article determined control actions, transfer functions of the object and phase graph of the control system.

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Zhu, Binrong, Behzad Nematollahi, Jinlong Pan, Yang Zhang, Zhenxin Zhou, and Yamei Zhang. "3D concrete printing of permanent formwork for concrete column construction." Cement and Concrete Composites 121 (August 2021): 104039. http://dx.doi.org/10.1016/j.cemconcomp.2021.104039.

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Zhao, Yun Bo, Chang Ming Hu, Yi Li Yuan, and Sha Nong Wang. "FEM Analysis of Cooperative Effects of Formwork Supporting System and Concrete Floor." Applied Mechanics and Materials 651-653 (September 2014): 1158–63. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.1158.

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This Currently, researches on formwork supporting system are mostly based on integrated stability, while the contribution of the cooperative bearing effects of the formwork supporting system and the concrete floor to the reliability of a structure is ignored. In this paper, the necessity of the existence of the formwork supporting system in the construction process of a structure’s roof boards is established by analyzing the cooperative effects of the formwork supporting system and the concrete floor of a subway transfer station under construction through double nonlinear numerical method.It is also concluded that flat paraboloid is the shape of the trend of the horizontal displacement of supporting formwork system under two-way load by using finite element analysis, and the open side of the paraboloid is opposite to the direction of the force, which is completely different to the decreasing trend from the top to the bottom of the horizontal displacement of the formwork supporting system under one-way load.

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Gaidukov, Pavel, and Evgeniy Pugach. "Prospects for the development of stay in plase formwork for low-rise buildings in cramped conditions." E3S Web of Conferences 258 (2021): 09030. http://dx.doi.org/10.1051/e3sconf/202125809030.

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The article considers existing and promising systems for the construction of slabs in low-rise buildings using stay in place (SIP) formwork. The main conditions for using these formwork systems are described and the disadvantages of existing structures are highlighted. Using the example of previously patented inventions, various trends in the development of formwork systems are revealed. The article deals with precast concrete structures of fixed formwork, modular structures of fixed formwork, various types of connections. Variants of fixed formwork with different types of installation and delivery of concrete mix, made of different materials and shapes are considered. The main individual features of each type of invention are highlighted, on the basis of which assumptions are made for the development of these systems. Based on the results of the analysis, the article offers technical requirements and a brief description of a promising formwork system for the construction of floors of low-rise buildings in cramped conditions.

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Liu, Cai, Qirong Wu, Xiaolian Wu, Mengzhu Han, Xin Guan, and Jinguo Lin. "Influence of slab structure on the performance of bamboo based concrete formwork." BioResources 15, no. 4 (August 12, 2020): 7503–16. http://dx.doi.org/10.15376/biores.15.4.7503-7516.

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To reduce the density of bamboo-based concrete formwork on the premise of meeting the performance requirements, the bamboo was first treated by cold plasma, and then by increasing the distance between the adjacent bamboo strips of the radial bamboo curtain in the middle layer, the internal porosity was increased. The production of lightened bamboo based concrete formwork, which meets China’s forestry industry standards, was achieved. Four groups of bamboo-based concrete formworks with different slab structures were designed. The key results showed that slab structures have an extremely significant effect on the density, MOR, MOE, IB, and TS of the bamboo-based concrete formwork. A group of optimal slab structures was obtained by comparing their physical and mechanical properties (1st and 9th floor-phenolic resin impregnated paper, 2nd and 8th floor-bamboo mat, 3rd and 7th floor-tangential bamboo curtain, 4th and 6th floor-radial spaced bamboo curtain). Based on the required physical and mechanical properties, its density was 0.62 g·cm-3, which was 27.1% lower than that of traditional bamboo plywood template (0.85 g·cm-3) circulating on the current market. This lightened BBCF can save raw materials, facilitate transportation and reduce labor intensity in the application process so that it will be widely used in building construction.

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Jin, Guo Hui, and Dong Sheng Yu. "Research on Safety of High Formwork Supporting System of Fastener-Style Steel Pipe in Concrete Structures." Applied Mechanics and Materials 578-579 (July 2014): 351–53. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.351.

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This paper analyzes the safety of high-formwork support system from material quality, computational design, structure erection to construction management system. And putting forward to specific construction safety measures combine with practical engineering. In desire to make the security of high-formwork support systems in concrete structures come true.

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Dong, Chen, Chen Ming, Cai Ouyang, and Li Pengkun. "Study on mechanical properties of a new type of prefabricated GRC mold shell." E3S Web of Conferences 136 (2019): 02030. http://dx.doi.org/10.1051/e3sconf/201913602030.

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The GRC formwork structural column adopts the factory-based vertical prefabrication production process, which can reduce the floor space, reduce the formwork loss, speed up the construction progress, promote the full decoration of the prefabricated building, and improve the efficiency of the assembly construction. major. In order to optimize the production process of prefabricated GRC formwork column, the overall stress system of GRC formwork structure is analyzed in the concrete pouring process, and the thickness of GRC formwork, the number of steel hoops and the GRC mode are considered. The influence of the shell cross-section size on the mechanical properties. The research results can provide reference for the optimization and design of prefabricated GRC formwork column production process.

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Kim, Seungho, Dong-Eun Lee, Yonggu Kim, and Sangyong Kim. "Development and Application of Precast Concrete Double Wall System to Improve Productivity of Retaining Wall Construction." Sustainability 12, no. 8 (April 23, 2020): 3454. http://dx.doi.org/10.3390/su12083454.

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The construction of most apartment underground parking lots utilizes reinforced concrete (RC) structures composed mainly of rebar work and formwork. RC structures lower construction efficiency and significantly delay the construction because they require a large number of temporary materials and wooden formwork. In this study, a precast concrete double wall (PCDW) system was developed to address the existing problems of RC structures and to improve the productivity of retaining wall construction. PCDW is a precast concrete (PC) wall in which two thin concrete panels are connected parallel to each other with truss-shaped reinforcement between them. PCDW can contribute to securing integrity, reducing the delay in construction, and improving quality. An overall process for the member design and construction stage of the PCDW system was proposed, and its improvement effects were examined regarding various aspects in comparison to the RC method.

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Kurakova, Oksana. "Use of formwork systems in high-rise construction." E3S Web of Conferences 33 (2018): 03026. http://dx.doi.org/10.1051/e3sconf/20183303026.

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Erection of high quality buildings and structures within a reasonable time frame is the crucial factor for the competitiveness of any construction organization. The main material used in high-rise construction is insitu reinforced concrete. The technology of its use is directly related to the use of formwork systems. Formwork systems and formwork technologies basically determine the speed of construction and labor intensity of concreting operations. Therefore, it is also possible to achieve the goal of reducing the construction time and labor intensity of works performed by improving the technology of formwork systems use. Currently there are unresolved issues in the area of implementation of monolithic technology projects, and problems related to the selection of a formwork technology, high labor intensity of works, poor quality of materials and structures, etc. are the main ones. The article presents organizational and technological measures, by means of which introduction it is possible to shorten the duration of construction. A comparison of operations performed during formwork installation according to the conventional technology and taking into account the implemented organizational and technological measures is presented. The results of a comparative analysis of economic efficiency assessments are also presented on the example of a specific construction project before and after the implementation of the above mentioned measures. The study showed that introduction of the proposed organizational and technological model taking into account optimization of reinforcing and concreting works significantly improves the efficiency of a high-rise construction project. And further improvement of technologies for the use of insitu reinforced concrete is a promising direction in the construction of high-rise buildings.

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Abreu, Marina Macedo de, and Alberto Casado Lordsleem Jr. "Aluminum formwork system: loss and productivity." Built Environment Project and Asset Management 9, no. 5 (November 11, 2019): 616–27. http://dx.doi.org/10.1108/bepam-04-2018-0070.

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Purpose The purpose of this paper is to establish and evaluate the concrete loss and labor productivity (LP) indicators in the concreting step of aluminum formwork system (AFS) in construction in Brazil. The loss and productivity indicators are directed to a regional database (Pernambuco, Brazil). Design/methodology/approach Case study was selected as the most appropriate approach. The methodology included data collection in the construction project with 10 residential towers of 320 apartments, in the city of Jaboatão dos Guararapes, Brazil, throughout 82 concrete pouring days using 415 concrete mixer trucks, with a total of 2,582.50 m3 of concrete. Findings The findings identified an average concrete loss of 2.6 percent and the LP indicator varying between 0.15 and 0.97 WH/m3. It could be verified that the loss indicators were influenced mainly by the learning effect associated to the qualification of the labor. In addition, the productivity indicators were strongly influenced by delays at the beginning of the concrete pouring and by problems coming from the sequence of concrete supply. Originality/value LP indicators are still literature restricted, especially considering only the concreting step. The direct observations of this study allow the identification of factors that inhibit productivity. The comparison of indicators for the concreting service between the ASF and the conventional system attests to the speed, low cost and efficiency of the system studied in this paper.

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Taher Ahmed, Mohammed, Rozana Zakaria, Rosli Mohamad Zin, and Rania Hussien Ahmed. "Environmental Performance for Two Formwork System Types: Conventional Formwork & Steel Formwork System." Applied Mechanics and Materials 525 (February 2014): 509–11. http://dx.doi.org/10.4028/www.scientific.net/amm.525.509.

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Environmental aspect is one of the important criteria that define and determine sustainability performance for concrete formwork system. This study is aimed to compare the performance of the most common types of formwork system Conventional Formwork & Steel Formwork System in responding to environment category of sustainability development using questionnaire survey distributed among construction experts. The steel formwork system gets 11.5 score points while conventional formwork collects 7.8 points of total 19.4 score can be achieved. Overall steel formwork performance surpasses the conventional formwork while their score for formwork reusable element was adjacent with only 0.5 score difference meantime steel formwork had override conventional formwork in impact on local environment element. Generally steel formwork system may conceder as more environment friendly than conventional formwork especially in waste generation and using renewable material.

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Liu, Li, Fang Wang, and Ju Chao Wang. "Influence of Concrete Pouring Sequence on Stability of Different Height High-Formwork Support System." Advanced Materials Research 838-841 (November 2013): 227–30. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.227.

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This article used ABAQUS finite element analysis software to established the high-formwork, analyzed effect on stability of the different height formwork by contrasting lateral displacement of various heights, discussed influence of concrete pouring sequence on stability of different height high-formwork support system in the construction process. From the simulated result, it can be seen that with the increase of height, the lateral displacement increased gradually when poured in dissymmetrical way, but the stability of high-formwork decreased, the result also provides evidence for code revision.

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Meng, Xian Hong, Chan Fang Zhou, and Jing Hai Zhou. "Lattice Concrete Wall Structure Optimization and Numerical Analysis." Applied Mechanics and Materials 71-78 (July 2011): 1628–32. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.1628.

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Polystyrene formwork of lattice concrete wall is a set of lightweight, insulation, sound insulation, fireproof, bearing multi-function in one of the "EPS new energy-saving" wall structure system. Through the polystyrene formwork structure forms of optimized improvement built in construction process of collapse produced high wall plate phenomenon. Do an axial compression ratio of 0.2 lattice specimens of reinforced concrete shear wall in axis pressure and reciprocating level forces test. The damage form of that wall for wall bottom beam-column central cross core ring crack and appear "X" type crack and are crushed. The mesh wall formed strong vertical limb and weak horizontal limb，belongs to the ductility structure , and has more yield , and energy dissipation capacity , and wall overall performance is strong , and avoid brittle failure , and has good ductility、deformation ability and bearing capacity of the characteristics of big .The finite element analysis and experimental results indicated that the ultimate bearing capacity of the wall are the same. For new formworks do wall by finite element analysis, in do not affect its aseismic capacity premise that wall structure forms are optimized design.

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Lusis, Vitalijs. "Formwork with Variable Geometry for Concrete Shells Production Technology." Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 2 (August 8, 2015): 63. http://dx.doi.org/10.17770/etr2013vol2.855.

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One of the main constructive materials in the building sphere is a precast concrete and fiber concrete. It is well influenced by scientific research basis, development and implementation of progressive technologies. The fiber concrete it is an ideal material with practically unlimited number of shapes. A nomenclature of concrete articles increases, it is working on different shape formation and processing. While preparation for this document started with the concept fabrication, it is necessary to understand the methods of construction variable geometry formwork of concrete thin-shell surfaces, both past and present as a point of departure. An understanding of this background helps provide an essential foundation for the exploration of new potential advances in the field of thin-shell construction. Obviously that is the reason for fiber concrete to be the most widespread constructive building material all over the world. In the article are considered shell development technology features and is evaluated technical and economical effectiveness of concrete shells with thin walls. Now variable geometry systems from flexible materials are developing and improving, there is a great potential followed by modern events in concrete technology. The results of laboratory experiments have proved that the technology can be used for fibro concrete shell production and construction.

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Hallowell, Matthew R., and John A. Gambatese. "Activity-Based Safety Risk Quantification for Concrete Formwork Construction." Journal of Construction Engineering and Management 135, no. 10 (October 2009): 990–98. http://dx.doi.org/10.1061/(asce)co.1943-7862.0000071.

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Wang, Xianfeng, Qi Chen, Jun Tao, Rui Han, Xiaobo Ding, Feng Xing, and Ningxu Han. "Concrete thermal stress analysis during tunnel construction." Advances in Mechanical Engineering 11, no. 6 (June 2019): 168781401985223. http://dx.doi.org/10.1177/1687814019852232.

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In order to propose an optimised construction plan and prevent and control the possible occurrence of cracks in concrete structures during construction, a detailed simulation of construction stages is required. The temperature and thermal stresses during the construction of a double-hole, double-deck concrete tunnel structure were analysed in this study, in which the analysis of the early-aged behaviour of a structure was performed considering actual construction conditions, and the cracking conditions were predicted. It was found that the temperature trends obtained from the simulated results were in good agreement with actual data, which indicates the reliability of the simulation results. In addition, the distribution of thermal stresses in the structure indicated that the tunnel structure was at risk of cracking at a number of stress concentration areas under the construction conditions. A parameter analysis of different factors, including the initial concrete temperature (25°C, 30°C, and 35°C), formwork stripping time (48 h, 72 h, and 96 h), and the construction season ambient temperature (summer and winter), was conducted. The formwork stripping time did not have a significant influence. It is recommended that the initial concrete temperature should be controlled to below 30°C during construction.

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Lee, Dongmin, Taehoon Kim, Dongyoun Lee, Hyunsu Lim, Hunhee Cho, and Kyung-In Kang. "DEVELOPMENT OF AN ADVANCED COMPOSITE SYSTEM FORM FOR CONSTRUCTABILITY IMPROVEMENT THROUGH A DESIGN FOR SIX SIGMA PROCESS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 26, no. 4 (April 9, 2020): 364–79. http://dx.doi.org/10.3846/jcem.2020.12188.

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System form is widely used when constructing concrete buildings and structures because it has high productivity and good concrete casting quality compared with traditional hand-set form. However, from a worker’s perspective, system form is still very harsh to handle because of its heavy weight, noise generation, and use of releasing agent, and it also attenuates the productivity of system formwork. Therefore, this study proposes the use of an advanced composite material-based concrete form for workers using a Design for Six Sigma (DFSS) process to improve constructability of system formwork. User requirements are systematically reflected in the technical characteristics of concrete form, and innovative principles are scientifically organized through the DFSS process that mainly consists of quality function deployment and theory of creative problem-solving methods. The proposed composite form showed improved performance in deriving high-quality formwork and worker-friendly working conditions compared with previous system forms. Additionally, this study demonstrated how the DFSS will be a valuable tool for technology development and systematic decision-making in building construction.

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Li, Jian Ping, Jie Ruan, Pin Tan, and Xian Jun Wang. "Simulation Analysis and Structure Optimization of Steel Structure Climbing Formwork with Material Properties Used in the Large Angle Leaning Bridge Tower." Applied Mechanics and Materials 540 (April 2014): 201–4. http://dx.doi.org/10.4028/www.scientific.net/amm.540.201.

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Steel structure climbing formwork has been widely used in bridge pier and bridge tower, etc. But the design of 30 degrees slope climbing formwork design is rarely involved. The climbing formwork which in the upper surface of leaning bridge tower is affected by concrete buoyancy and the downside is affected by concrete gravity .That cause insufficient stiffness,deformation of the template,non-uniform cross-section of the bridge and large angle deviation which have great harm to the bridge quality .This paper which combined the construction project of Huaibei Xiangwang Bridge establish the mode of climbing formwork, then, import the mode to the Workbench14.5 proceeding simulation analysis. Getting the stress and deformation of the climbing formwork, check the strength and stiffness .Then optimize the structure of climbing formwork to ensure the stiffness and control the deformation of the template. The stress of downside climbing formwork after optimization is uniform and maximum stress is reduced about 30% .This paper provide a reference to the design of the climbing formwork used in the large angle leaning bridge tower.

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STORCH, I. S., J. G. S. DOBELIN, L. C. BATALHA, and A. L. SARTORTI. "Self-supporting tests in lattice joists subject to negative bending." Revista IBRACON de Estruturas e Materiais 10, no. 6 (November 2017): 1366–95. http://dx.doi.org/10.1590/s1983-41952017000600011.

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Abstract During the construction of bridges, cantilever roofs and eaves, assembling formworks and scaffold that will support the slabs is a point of difficulty in the construction phase. Therefore, it is relevant the study of the lattice joists which serve as self-supporting formwork, supporting its weight, the weight of the fresh concrete, the weight of workers and the weight of concreting equipment. The analysis of the bearing capacity of lattice joists subject to negative bending with base concrete opening enables checking the maximum span that each lattice truss model bears, either cantilevered or between continuous spans with reduced or no scaffold. The concrete opening enables the monolithism between the slab and its support. This paper presents the results of tests on lattice joist with concrete opening. By the results analysis, formulations for designing the spacing between prop lines were found. The results are promising and indicate great possibilities of using lattice joists with concrete opening over the supports (beams), in order to optimize the slab shuttering.

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Kromoser, Benjamin, and Patrick Huber. "Pneumatic Formwork Systems in Structural Engineering." Advances in Materials Science and Engineering 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/4724036.

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Concrete as a construction material is characterized by high compressive strength, low tensile strength, and good casting ability. In order to fully utilize the potential of this material, the form of load-carrying structures has to be designed according to the stress distribution in the structure. Partially hollow structures, such as hollow beams, or doubly curved structures, such as shells, have favorable characteristics. In hollow structures, material savings are achieved in the individual building components by locally reducing dimensions. Concrete shells, if designed properly, are able to span over large areas by transferring the loads mainly by membrane stresses. The main problem with these structures, however, is the high effort required for producing the complicated formwork. One possibility of reducing this effort is to use a pneumatic formwork. This paper describes different pneumatic formwork systems invented in the past 100 years and presents the latest developments in this area. The many types of possible applications are divided into three categories in order to obtain a clearer overview. Finally, a new construction method, called “Pneumatic Forming of Hardened Concrete (PFHC),” is presented. This method was invented at the TU Vienna and uses the pneumatic formwork in a novel way.

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Lwambuka, Ladslausi. "Optimal Utilization of Timber Poles as Structural Members of Formwork." Tanzania Journal of Engineering and Technology 30, no. 1 (June 30, 2007): 29–35. http://dx.doi.org/10.52339/tjet.v30i1.394.

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Timber poles of the type “Mirunda” are commonly used in East Africa as formwork support structures for casting of reinforced concrete slabs, beams and canopies. It is also widely known that the “Mirunda” poles as structural members of formwork are massively used without any structural consideration and guidance. This common practice has resulted into wastage of natural resources and escalated construction costs. This study has attempted to establish the load bearing capacity of randomly selected “Mirunda” poles through laboratory testing. Using an existing construction site as a casestudy, the results have been used to establish the actual number of timber poles required to support freshly castreinforced concrete slabs, beams and canopies. The loading has been assumed for normal accessibility as perspecifications in BS 6399: Part1 (1984).with a dynamic factor arising from the impact of dropping the concreteonto the formwork as well as the dynamic effect of the concrete vibrating machine. A comparison has beenmade between the actual requirement and the quantity of timber poles counted on site. On basis of the studyfindings appropriate recommendations have been provided on how “Mirunda” poles can be optimally utilized as structural members of formwork.

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Schleicher, Simon, and Michael Herrmann. "Constructing hybrid gridshells using bending-active formwork." International Journal of Space Structures 35, no. 3 (June 16, 2020): 80–89. http://dx.doi.org/10.1177/0956059920924189.

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Aiming to promote a more sustainable approach to material utilization in architecture, this article presents an alternative construction method for lightweight and efficient concrete structures. The strategic focus is placed on building wide-spanning roof structures like vaults, domes, and freeform shells with the lowest possible input of raw materials and energy. To achieve this objective, the article explores the novel idea of using bending-active structures, made from millimeter-thin carbon fiber strips, as lost formwork and structural reinforcement for the production of hybrid gridshells. After a general introduction to the state-of-the-art in concrete construction, the authors discuss opportunities and challenges related to flexible formwork designs and their possible impacts on the building industry. Relying on the example of a built prototype, the authors present a promising design methodology and analyze the gridshell’s geometrical and structural characteristics throughout different stages of the construction process. The article concludes by discussing the added value of this research and identifying the key aspects that need to be considered in the further development of this construction method.

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Kovářík, Michal, Pavel Svoboda, and Henri Hubertus Achten. "Limits and Potential of 3D Printing Technologies for Construction of Concrete Shells." Solid State Phenomena 292 (June 2019): 249–56. http://dx.doi.org/10.4028/www.scientific.net/ssp.292.249.

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Concrete shells are a very effective type of building structures due to their ability to bridge large spans with minimal construction thickness. This type of building structures built on the medieval vaulting techniques and, regarding the use of reinforced concrete over the last 100 years, it has overcome the limitations of the masonry vaulting technologies and enabled to increase the span of structures to tens of meters. The construction technology to realize concrete shells using monolithic casting into formwork is besides abovementioned advantages characterized by high labour and thanks to the cost and manufacturing intensity of double curved formwork panels it allows economical realization of only selected structural geometries. Its considerable limitation is, besides the costly production of double curvature formwork, also the laborious installation of formwork and falsework structures. The solution seems to be in line with the upcoming transition to Construction 4.0 robotizing the construction technology of shells that could create a similar increase in productivity and design possibilities as was the technological transition between vaults and shells. One of the promising technologies of robotic production seems to be digital fabrication methods and, in particular, 3D printing or in other words additive manufacturing. This wasteless technology, which has been used to date for experimental projects mainly for the realization of vertical bearing structures, has, despite the first attempts at realizing vaults, a number of technological limitations. In this article, authors aim to summarize and indicate possible constraints of on site 3D printing of domes. They further indicate the possible ways to overcome these limitations and suggest two different means of on site 3D printing of hemispherical dome and the dome based on the catenary profile using extrusion nozzles with different profiles. Finally they discuss the Eurocode requirements for concrete shells and suggest technological solutions for on site 3D printed shells in terms of structural reinforcement.

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Zhou, Shuang Xi. "Preparation and Application of a Self-Thermal and Insulation-Ribbed Floor." Applied Mechanics and Materials 353-356 (August 2013): 2896–99. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.2896.

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With the cementitious composite formwork without being removed, steel wire frame and formwork technology, a self-thermal and insulation-ribbed concrete floor is made. Through the tests of bend-bearing capacity of self-thermal and insulation-ribbed floor, the results show that the loads of the self-thermal and insulation-ribbed floor meet the limits on deflection requirements according to the design of concrete structures. Besides, the floor has a better thermal and soundproof function compare to the ordinary concrete beam and slab, and its comprehensive cost of construction is low.

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Yakovleva, Irina, and Valentina Kurochkina. "Arrangement of construction joints in cast-in-place slabs." E3S Web of Conferences 97 (2019): 04023. http://dx.doi.org/10.1051/e3sconf/20199704023.

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Within latest decades cast-in-place construction of residential houses has been actively developed. Works on erection of cast-in-place frame of the building are normally performed by phases, which results in a necessity to arrange construction joints of concreting. In accordance with regulatory documents, it is allowed to arrange construction joints in any place of the slab, in parallel with its less side. As well, it is necessary to observe the technology for joint arrangement. As practice shows, observing only technology of construction joint arrangement is insufficient to provide for strength properties of cast-in-place reinforced-concrete slabs. This article provides an analysis of actual geodetic pre-construction surveys, design and theoretically-calculated solutions; case study is a multistoried building under construction. On which basis, excessive slab deflections in the places of construction joints, were detected. It is established, that the main reason for deflection occurrence is early removal of slab formwork and installation of supports for temporary supporting. On the basis of obtained findings authors make conclusions regarding compulsory observance of the technology for construction joint arrangement, regarding a necessity to remove formwork according to common standards 70.13330.2012; as well, it is recommended to leave formwork under construction joints until concrete gains 100% of ruggedness.

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Ghulyan, Armine B., Garegin L. Tepanyan, and Boris J. Sargsyan. "Problems of Formation of Complex Monolithic Reinforced Concrete Structures." Key Engineering Materials 828 (December 2019): 153–57. http://dx.doi.org/10.4028/www.scientific.net/kem.828.153.

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The features of the structures of complex monolithic reinforced concrete structures are given, the necessity of their organizational and technological design to ensure quality, reduce the duration and safety of construction and installation works is substantiated. A fragment of the formwork for complex curvilinear beams is presented, where the permanent and temporary loads, the permitted steps of the main and secondary beams and remote scaffolds for the PERI and CRAMOS modular formwork systems, which are more common in RA, are calculated in detail.

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Zhang, Yan Cong, Ling Ling Gao, and Jun Min Shen. "Vibration Characteristics of Air-Entrained Concrete Based on Slipform Construction." Applied Mechanics and Materials 204-208 (October 2012): 1549–52. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.1549.

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Vibration characteristics of air-entrained concrete was analyzed by vibration slump loss, formwork ability and vibration viscosity coefficient through comparative testing. The results showed that: air-entrained concrete has a characteristic that high slump in vibrating and low after. It was significance to construction with slipform paver. Air-entraining agent improved the concrete structural viscosity under high-frequency vibration was the reason for this characteristics.

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Ioannou, Socrates, Atef Badr, Kaloyana Kostova, Kevin Paine, and Tim Ibell. "Utilization of Fabric Formwork for Improving the Durability of Concrete from Supersulfated Cement." Key Engineering Materials 711 (September 2016): 615–21. http://dx.doi.org/10.4028/www.scientific.net/kem.711.615.

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In this paper, the durability of fabric formwork-based concrete made from supersulfated cement was studied. The study involved comparison of chloride and carbonation resistance, pH values, and water absorption between of surfaces of SSC, the one being cast and the other cast in fabric formwork. It was shown that the use of fabric formwork minimized the pore volume near the surface, maintained the pH values at higher profile depths and showed improved durability when compared to the mould-cast surface. Carbonation depths were reduced by approximately 35% and calculated ab sorption rates were found to be approximately 40% lower at the fabric cast surface, indicating that fabric formwork is a promising aspect towards promoting the comeback of SSC in construction.

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Tejeda-Dominguez, Fernando, David A. Lange, and Matthew D. D'Ambrosia. "Formwork Pressure of Self-Consolidating Concrete in Tall Wall Field Applications." Transportation Research Record: Journal of the Transportation Research Board 1914, no. 1 (January 2005): 1–7. http://dx.doi.org/10.1177/0361198105191400101.

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The growing interest in the use of self-consolidating concrete (SCC) for a wide variety of structural applications has initiated a reexamination of its properties and current construction practices and how they compare with those of conventional concrete. One property of interest is the formwork pressure of SCC and how it relates to that of conventional concrete. This work presents the results for three tall walls (28, 21.7, and 13 ft tall) cast slowly with SCC and a 10.6-ft-high column poured quickly by using the same concrete used in one of the walls. The research demonstrates that the pressure of SCC against the formwork drops quickly just after the concrete material is placed. Measurements from the walls poured slowly show that the maximum recorded pressure falls far below the hydrostatic pressure and is closely related to the pouring rate. The experiments also reveal that the formwork pressure exerted by SCC can be revitalized if the SCC is vibrated, even if stiffening is already in progress.

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Omer, Muhammad I., and Dilshad K. Jaf. "Evaluation of Concrete Quality for Reinforced Concrete Frame Members Exposed to Natural Fires at Early Ages Using in situ Test Methods." Open Civil Engineering Journal 13, no. 1 (December 31, 2019): 201–9. http://dx.doi.org/10.2174/1874149501913010201.

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Background: In recent years, numerous reinforced concrete buildings have been constructed in Iraq and some developing countries. Fire accidents occur in wooden formwork especially during the summer season due to problems associated with the construction procedure and on-site management. And fires can erupt during the construction stage of buildings. Introduction: Generally, if fire accidents occur in a wooden formwork, in these situations the concrete in the field is at an early age (i.e., “young”). The internal structure and chemical composition of early-age concrete are different from that of the carrier due to incomplete hydration at an early age. This study aimed to evaluate the strength of reinforced concrete frames at early ages when exposed to natural fire. The evaluation of existing buildings is an important issue that involves researchers and engineers in many countries. Methods: The experimental program consisted of constructing three full-scale reinforced concrete frames that are then exposed to natural fire. When the concrete age reaches three and five days by firing its formwork, the concrete quality of the structure was evaluated via ultrasonic pulse velocity as a nondestructive measurement. Core test was used as a destructive technique to implement a relationship between compressive strength and nondestructive measurements Results: The results showed that the frame exposed to natural fire early was generally more affected than the other frame, and its compressive strength was reduced close to 33%. The results also showed that the ultrasonic pulse velocity test for the structural elements was smaller than those of the core test Conclusion: It can be concluded that the current assessment methodology must be evaluated to provide practical suggestions that can enhance the reliability of assessing the in situ strength of existing concrete structures by nondestructive tests and cores.

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Journal articles on the topic 'Concrete construction formwork'

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