Beton esaslı, büyük boyutlu prefabrike panellerin fabrikada üretimi ve üretim sorunları

Abstract

Bu çalışmada beton esaslı, büyük boyutlu prefabrike panellerin kalite ve ömründe önemli bir etken olan, fabrikada üretim şartlan ve üretim aşamalan sırasında karşılaşılan zorluklar ve sorunlar incelenmiştir. Tezin hazırlanması sırasında yararlanılan, çeşitli kaynak ve literatürlerden başka, Ytong, Kutlutaş, Afa ve Gök inşaat Fabrikalan ve Sadri Şener Evleri inşaatında yerinde incelemeler yapılmış, üretim aşamalan ve üretim aşamalan sırasında karşılaşılan zorluklar ve sorunlar hakkında yetkili kişi ve çalışanlardan bilgi alınmıştır. Tezin ilk bölümünde, girişte kısaca konuyla ilgili tanımlara yer verildikten sonra, ikinci bölümde yapımın endüstrileşmesine (tezin konusu olan beton esaslı büyük boyutlu panel sistemlerin de bir endüstrileşmiş yapım sistemi olduğu için) yer verilmiş ve bu konuda çeşitli literatürlerden bir derleme yapılmış ve bu arada da endüstrileşmiş yapımın Türkiye'deki yerine de kısaca değinilmiştir. Üçüncü bölümde panellerin üretiminde kullanılan ve panel kalitesinde etkin rol oynayan tüm malzeme ve elemanlar araştınlmış ve incelenmiştir. Dördüncü bölümde ise panellerin üretimi ve üretim aşamalan ele alınmıştır. Sonuç bölümünde ise elde edilen verilerden yola çıkılarak, üretimde aksaklıklann doğabileceği aşamalarda izlenebilecek öneriler verilmeye çalışılmıştır. Tüm bu çalışmanın yapılması sırasında, gezilen fabrikalardan elde edilen bilgi ve görüşlerden de faydalanılmış, yerinde tesbit ve konuya daha iyi açıklama getirmek amacıyla uygun görülen yerlerden fotoğraflar çekilmiştir.

In this procedure, the factory production of large panels from concrete, which have found a popular use field in our country and the difficulties faced in the stage of production and problems. Along with verious literature investigations have been mentioned for factories (Ytong, Kutlutaş, Afa, Gök) and in the shipyard of Sadri Şener houses, an investigation has been made in site and information has been taken from authorities. In the first part of the thesis some definitions have been given along with a short instruction. However in the second part because of the presence of industrial production systems in prefabric panel systems.the production industrialization has been examined : As a result of structure sector industrialization.prefabric systems are a structure type, exposed to view. Industrialization in structure, from finished product to raw material, namely within the structure transition process, tool, labour and to obtain the most rational use of these times all the precautions to be taken are on the verge of embracement. However prefabrication being an industirial production system, present staff or to establish production components ; to bring the shipyard workers within the possible measurments to the factory working position and is a construction built with the assemblage of the present staff on production site. Briefly, it can be accepted that the aim of prefabrication is to complete the production in the factory and to place it in it's arranged area in the shipyard. As seen in other industrial branches the main target of fabrication is briefly to rationalize. Rationalisation in structure is to present establishment tools, better, labour- power.quality and to produce quil a lot of amounts of construction or to produce the same amount of construction faster but with less expenditure. To reach this purpose, industrial technic and the usage methods in the stages of production process, is necessary. The advantages to be gained with rationalisation instructre can be generalized follows : ?IX- - Profit and continuity of production. - To benifit in the best way from tuois and labour work. - To reduce seasonal stand stills. - To reduce production period in the shipyard. In industrial production the reasons of why prefabrication has inclined towards technology, depends on theree basic closely relaited advantages. - Low total cost (production+maintenance+administration cost) -Fast production - High quality Int is possible to gather the industrial production methods in two groups - The rationalizism of the traditional production process (extended traditiolal production) - Formation of the structure from ready components(prefabric structure). - In the rationalizism of traditional production process ; while the production time in shipyard is being restricted, production speed, source _use, developed tecnology and equipment use are all tried to be included in the production. In the method of this production ; the newness in, mould system, concrete enumeration technics, equipment systems and tools are used. To constitute the production with present components ; all the elements which are making up the structure or all finished structure that are produced before and mounded later, to reduce production, period to minimum fabrication process and this is a production system that has brought the biggest organization differences. It is possible to group the purposes as follows : ? To draw the structure procedures outside the shipyard. ? To reduce seasonal dependence while production.. To carry out the procedures parallel to each other.. To economize tools, Labourwork and time.. To procure a better quality control. Industrial systems can be grouped as follows in respect to production and marketing : -Closed - Half Closed - Open Systems These topics are mentioned in detail in the thesis. In industrialized production the standarts and tolerances have a seperate importence ; with standardization in production;lt is aimed to bring the standarts to render the conciousness of the consumer and producer, also the results gained after long efforts from scientific and technological levels to be easily understood and practiced. On the other hand tolerance is a valve to define, the dimensions of the staff at the end of production or to define the exceptable forms wanted in the project or the proportion to exceptable deviation. But yet still in our country, the standart has been developed concerning mistakes about concrete founded prefabric panel dimensions and tolerances. Concrete founded prefabrication, long lasting, fast, quality and along with this to provide construction stability, the strength of knots, problems in calculation and details, the need of experiments in calculation, the transfer of present staff and problems in mounting has a few disadvantages. Especially in the last, industrial production systems are quiet popular in our country. But in our days, because of economical problems and therefore because of no investment the speed of industrial production has been cut down, traditionel production has become more prefered. In the third part of the thesis, after a short instruction about panels the imput used in producing concrete founded panel systems : - Material input (cocrete, concrete steel, special materials used panel production) - The input of materials used in productions (moulds and other materials used in production) and -Labour work, have been mentioned. The concrete used in the production of concrete founded panels, has brought a clearness to the conception of heavy, light and normal concrete. Busides while the concrete topic is mentioned, socket, relay hydrotation, heat of hydrotation or contribution materials used to change some specialities here has also been classified and investigated. Other than these the moulds that are very important in panel production have been investigated in details. Moulds are the first to come in the tools used for the production of concrete prefabric panel. They are the staff used to benifrt in gaining dimentional and formal characteristics. According to the situation of mould production used in the production of present staff. We can seperate them in two groups, they are as follows : - Horizontal and -Vertical Moulds The choice of moulds can be indicated according to the staffs quality (single or a lot of stages etc.) - Horizontal Moulds ; In the present staff production, horizontally situated moulds which could either be stationary or moving, are made generally from a sheet of iron or steel. On top of a production table, with the joining of various side profiles which can give a possibility of different dimensional and types of staffts. With these kinds of production for -xi- moulds in production, the establishment of equipment and needs and stabilization is much simpler according to vertical moulds. The production of empty and staff with a chest of drawers has a possibility of gaining different surface texture for alot concrete enumeration of layers and stages. - Vertical Moulds ; They are moulds made from a sheet of iron or steel where the concrete enumeration is made vertically. They are the most developed battery moulds. They are systems made up of indipendent vertical moulds where more than one (genarally 8-16 ceils), mouds which are one by one perpendicular and adjacent to each other. In vertical moulds there is no possibilty of alot of stage production and because of this a surface texture cant be formed. The stabilization of equiment and needs are very difficult. In these type of moulds, because of the pour of concrete from an height, there is a danger of accumulation of the agregation in the separation and mixture of the concrete. Staffs with emptiness and chest of drawers cannot be produced. In spite of the negative direction of vertical moulds they have positive sides such as being close to the end and gaining qualified products (in the lower limit or at exact measurment of tolerance). In the production of the prefabricated elements, various materialis (such as wood, processed wood, steel, aluminum, polyester etc.) can be used as the inner surface of the mould. In the fourth Section of the thesis, production of the concrete based, large size prefabricated elements in factories, the stages of this process, and the problem faced through these stages are discussed. There are two types of panel production : - In the worksite - In parmanent workshops. There are also two types of production in the worksite : - Production of large size elements, where transportation and interim storage would create problems;and - Production in open-top or top-covered workshops set up in the work-site. Production in the open-top or top-covered workshops set up in worksite is a proper method when the permanent work shop is far from the site of construction, or when the transportation is either impossible, or the volume of production is large enough to meet the additional cost of transportation. Production in permanent workshops gives the possibility of better installation of machinery, also better quality control. The most important reason of the production in this type of workshop is the permanence of the work capacity. The negative aspects of this system is the high cost of selling it up and its operation, the amortization, which would take few years, working in full capacity. In general, the permanent workshops consist of three sections : The main production area, auxiliary sections, and storage are. In the permanent workshops the production of prefabricate delements are of two kinds : - xii - a- Production in fixed molds, b- Production in mobile molds. a- Depending on the instruments used in the operation.there are theree kinds of factories producing in fixed molds : - Those where in the production and storage operations cranes with mobile bridge are used. - Those where in the production process cranes with moving bridges are used, where as in the storage tower cranes are employed. - Those factories the roof of which can be opened up.and where in the production process tower cranes are used, but the supply of concrete is achieved by forklifts. b- Factories using mobile molds (with conveyor system) are also divided into three - Integrated units - Conveyor fed factories - Conveyor fed vibrating rollar installations. The production pocess in the permanent factories consist of three centers - Concrete mixing center - Molds and accessories center - Production hall. - Operations in the concrete mixing center : The supply of the needed material for concrete (that is to say the purchasing, grouping, and the storage of these items) all sort of measuring operations related to these items ; mixing there of, and conveying the mixture to the moulds. - Operations in the moulds and accessories center : The supply and the preparation of the steel which will be used in the panels, cleaning of the accassories, conveying the accessories to the molds, either by man power, or, if they are too heavy, by cranes etc. - Operations in the production hall : As it can be understood by the name, this is where the molds are prepared, surface covering materials, and the accessories are placed, and the concrete is poured. After the concrete is poured, by using various vibrators, the concrete is pressed down and its resistance is inereased. When using harizontal moulds, the upper surface needs to be improued. There are several methods to do so. If there is any defect, they would try to revise it. If this is not possible the product can be saved to be used in other and less demanding constructions. In the fifth and the last section of the thesis, production of large size, concrete- based panels and the problems to be faced in their production and the way to got rid of these problems are plained.