Thesis (MScEng)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Hybrid concrete construction (HCC) is a construction technique that makes use of both in-situ and pre-fabricated concrete products by making optimum use of the advantages of both these methods in the same project. Although the advantages of this building method is well recognised throughout the world and a feasibility study illustrated that HCC is a suitable building method in South Africa, it remains under-utilised in the country. HCC encourages early involvement from the project team and provides clients with the best value projects and a "win-win" situation for the project team during the project development. The objective of this study is to identify barriers that prohibit an increased utilisation of HCC for the South African construction industry. Additionally, it provides possible solutions to overcome these barriers. These proposed solutions are similar to the programmes and methods that are implemented in other countries to improve their HCC utilisation. Furthermore, drivers are identified in this study to implement these solutions in the industry and a proposed "change model" is developed for private companies to assist with the change process. This study is unique because current South African conditions are used to establish the barriers and solutions. Furthermore, it takes into account that not all countries have such progressive construction industries as the European markets and therefore it considers solutions and drivers that are suitable for less advanced industries such as South Africa. The model that is proposed is applicable to any industry regardless of its nature or country. Although the United Kingdom is not the widest user of pre-fabricated concrete products, their HCC research is extensive, making it a suitable comparative country for the South African construction industry. During the investigation, the procurement methods in South Africa were found to be traditional and do not allow for early involvement or partnering in the project team. To obtain early involvement, it is critical to initiate methods such as design-and-build, contract management or public-private-partnerships during the procurement phase. Decision and design assistance from the whole project team and software tools are essential when HCC is considered. Because the South African construction industry does not provide such support it is advised here to incorporate contractors from an early stage and to develop software tools that can assist during the decision making and design process of HCC structures. The industry does not provide the project team with sufficient training programmes that increase knowledge of HCC. Training programmes that are cognitive stimulating must be developed for the industry. Furthermore, a database is required to illustrate the utilisation of different pre-fabricated products and in different projects within South Africa. Labour-intensive construction regulations and green building techniques (not compulsory) are promoted in South Africa. Labour-intensive programmes should consider the negative impact it has on the labourers and consider HCC as a building technique because the pre-fabricated elements are manufactured in a controlled and safe environment. It is advised that the toolkits that are used for green building accreditation, must be revised to accommodate the additional benefits such as less waste generation, that HCC offers to a project. Regardless of the country in which HCC is utilised, the environment must be acceptable for the innovation. By analysing the criteria that influences the use of HCC in a country and adding weighting functions to these criteria, the acceptability towards the innovation can be obtained. Furthermore, public clients and companies are recognised here as drivers of change. While public clients can commit to HCC for the cost, labour-intensive factories, green building methods, improved health and safety, training for labourers, private companies can utilise HCC to provide best value to a project. A model is proposed here for innovative companies that will allow them to change not only the company, but the industry towards a HCC "mindset". / AFRIKAANSE OPSOMMING: Hibriede beton konstruksie (HBK) is ’n tegniek waarby beide voorafvervaardigde betonelemente en in-situ beton in dieselfde projek gebruik word ten einde voordeel uit beide metodes te trek. Alhoewel die voordele van die konstruksietegniek wel bekend is in talle lande van die wêreld en ’n uitvoerbaarheidsanalise getoon het dat HBK ’n voordelige konstruksiemetode vir Suid-Afrika is, is dit tans onderbenut in die plaaslike sektor. HBK bied vir kliënte projekte van goeie waarde en omdat dit vroeë betrokkenheid verg vanaf die projekspan, resulteer dit ’n "wen-wen" situasie tydens die projekontwikkeling. Die doel van hierdie studie is om die hindernisse te ondersoek wat veroorsaak dat HBK nie meer gereeld in Suid-Afrika gebruik word nie. Ten einde die effekte hiervan te verminder, word moontlike oplossings vir hierdie hindernisse voorgestel. Die oplossings is gebaseer op tegnieke en metodes wat geïmplimenteer word in ander lande waar HBK gebruik word. Rolspelers wat hierdie verandering na HBK kan dryf word geïdentifiseer en ’n model om verandering binne ’n maatskappy te lei word voorgestel om die rolspelers te ondersteun tydens die proses. Hierdie studie is uniek omdat dit inligting gebruik van die huidige situasie van die Suid-Afrikaanse konstruksie-industrie om die hindernisse en oplossings te identifiseer. Omdat nie alle konstruksie-industrieë so vooruitstrewend is soos in Europese lande nie, is die oplossings en rolspelers relevant vir enige land wat ’n industrie het wat soortgelyk is aan Suid-Afrika. Die model wat voorgestel word is ook relevant tot enige industrie afgesien van die land waar nuwe tegnieke geïmplimenteer word. Alhoewel dit bevind is dat die Verenigde Koningkryk nie die grootste gebruikers van HBK is nie, is hulle navorsing in die veld omvattend. Daarom word die Verenigde Koningkryk beskou as ’n voorbeeld om Suid-Afrika se konstruksie-industrie mee te vergelyk, asook om inligting van HBK te verkry. Tydens die studie is bevind dat die projekaanstellingsmetodes van projekte in Suid-Afrika tradisioneel is, aangesien dit nie toelaat vir vroeë betrokkenheid of vennootskappe binne die projekspan nie. Om vroeë betrokkenheid te verkry, is dit noodsaaklik om van ontwerp-en-bou, kontrakbestuur of publiek-privaat-vernootskappe gebruik te maak. Tans is daar geen hulp wat aan ontwerpers verleen word ten opsigte van besluitnemingsmodelle en ontwerpsagteware wanneer HBK oorweeg word in Suid-Afrika nie. Die behoefte aan sulke bystand dui daarop dat sagtewarepakkette ontwerp moet word wat toepaslik is vir Suid-Afrika se konstruksie-industrie. Die industrie bied nie doelgerigte en genoegsame opleidingsprogramme aan om die industrie se kennis van HBK te verbreed nie. Addisionele opleiding wat kognitiewe stimulasie sal bied vir die hele projekspan word aanbeveel. ’n Databasis wat HBK projekte insluit, moet geskep word om die industrie bloot te stel aan die verskillende moonlikhede. Arbeid-intensiewe konstruksie-regulasies asook groen konstruksietegnieke (nie wetgedrewe nie) word sterk bevorder in Suid-Afrika. Dit word hier aanbeveel, dat voorafvervaardiging se addisionele voordele in ag geneem word wanneer hierdie regulasies en tegnieke relevant is. Hierdie voordele sluit onder meer in: die veiligheid wat aan werkers gebied word in arbeid-intensiewe fabrieke en die vermindering van afval in HBK projekte. Afgesien van die land waarin HBK gebruik word, moet die omgewing ontvanklik vir die tegniek wees. Deur verskillende kriteria te analiseer wat die gebruik van HBK beïnvloed binne ’n land en geweegde faktore daaraan te koppel, kan die ontvanklikheid van die innovasie bepaal word. Laastens word publieke kliënte en maatskappye as die drywers (of katalisators) wat verandering kan meebring, beskou. HKB bied onder andere die volgende voordele aan publieke kliënte: koste-effektiwiteit, arbeid-intensiewe werk, groen konstruksie, beter gesondheid, veiligheid en opleiding vir werkers. Maatskappye kan gebruik maak van HBK om waarde tot hul projekte toe te voeg. ’n Model word hier voorgestel om innoverende maatskappye in staat te stel om nie net hulself nie, maar ook die industrie as ’n geheel te help om ’n gesindheidsverandering jeens HBK te skep.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Construction of structural concrete frames may take place by using either cast in-situ or precast methods. With the cast in-situ method, these elements are constructed on the construction site as needed. Precast construction on the other hand is more resembles a line. The elements are constructed in a precast yard in a systematic fashion and once completed, they are taken to the construction site where they are to be erected. This study identifies the aspects and attributes which influence the quality of concrete during the construction phase of these two construction methods. The study is independent from the conceptual or design phase. Information regarding these aspects and attributes were obtained from literature and from contractors in industry through interviews and site visits. The literature review also focuses on quality management techniques and factors that influence quality in the construction environment. The information obtained from the site visits and literature was used to design a survey which was sent out to a number of respondents. A comparison between in-situ and precast construction was made based on the results of the survey. The synthesis of the research findings can be used by project teams to help them decide on the choice between in-situ and precast construction. It was found that precast construction is better for durability, and fitness for purpose is less complex for the in-situ solution. Recommendations for future studies are provided at the end of the document. / AFRIKAANSE OPSOMMING: Konstruksie van beton struktuurrame kan plaasvind deur die gebruik van in-situ of voorafvervaardigde metodes. Met die in-situ metode, word hierdie elemente op die terrein gebou soos benodig. Tydens voorafvervaardigde konstruksie aan die ander kant is die konstruksie soortgelyk aan 'n produksielyn. Die elemente word gegiet in 'n voorafvervaardingsterrein in 'n sistematiese wyse, en sodra dit voltooi is, word dit na die konstruksie terrein geneem waar dit opgerig word. Hierdie studie identifiseer die aspekte en eienskappe wat 'n invloed op die kwaliteit van beton het tydens die konstruksiefase van hierdie twee konstruksie metodes. Die studie is onafhanklike van die konseptuele of ontwerp fases. Inligting rakende hierdie aspekte en eienskappe is verkry uit die literatuur en van kontrakteurs in die bedryf deur middel van onderhoude en besoeke. Die literatuur fokus ook op die gehalte, bestuurs-tegnieke en faktore van gehalte in die bou-omgewing. Die inligting is verkry deur ‘n vraelys wat aan 'n aantal respondente gestuur is. 'n Vergelyking tussen in-situ en voorafvervaardigde konstruksie is vervolgens gemaak op grond van die resultate van die opname. Die sintese van die bevindinge kan gebruik word deur projek spanne om hulle te help besluit oor die keuse tussen in-situ en voorafvervaardigde konstruksie. Die resultate dui daarop dat voorafvervaardigde konstruksie beter is vir duursaamheid, maar passing op terrein is minder kompleks vir die in-situ oplossing. Aanbevelings vir toekomstige ondersoeke word aan die einde van die studie gemaak.

Närvaron av döden ökar värdet av livet. I ett samhälle som gömmer undan livets slut fyller ett krematorium ett syfte om att påminna och visa den som vill se. Programmets nyanser blir en skala från kännedom till bevittnande och byggnaden tar en självklar plats på begravningsplatsen och i samhället. För den som redan befinner sig i sorg har naturen ett allmängiltigt, tröstande värde. Växtlighet tränger sig in och minner om en tid då livet börjar om. Byggnaden är uppbruten för att bli ett landskap i sig och i mellanrummen kommer naturen in på ett påtagligt sätt. Utifrån går det att urskilja byggnadens signifikanta delar: Ugnshall, kylrum och byggnadens fem innergårdar. Siktlinjerna har varit mycket viktiga i projektet. Interiört för att känna en närhet till naturen och exteriört för att förbipasserande ska förstå krematoriets huvudsakliga delar; Kistans ankomst, dess färd från kylrum till ugn och slutligen som aska till en värdig förvaring i väntan på urnsättning. / The presence of death increases the value of life itself. In a society that hides away the end of life a crematory has a purpose to remind and reveal it to whoever wants to interact. The program of this building transforms into nuances at a scale from knowledge to witnessing. This crematory takes a prominent place at the cemetery and in the community. For those who are already in the mourning process, nature has a universal, comforting value. Vegetation intrudes into and reminds us of a time when life starts over. The building is scattered to become a landscape in itself. In the gaps nature grows. From outside the building’s significant parts can be distinguished: Furnace hall, cold store and the five courtyards of the building. Sight lines have been very important in the project. Internal to feel a closeness to nature and external to  make passers-by understand the typology’s main processes; The arrival of the coffin, its journey from the cold storage to the oven and finally the ash’s way to a dignified storage  for the urn until it has a permanent place.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The construction industry is a competitive market and contractors need to keep up-to-date with new construction methods and technologies. Project teams in South Africa are required to make decisions during the early stages of construction projects. These decisions often need to be made in a short time period, and include the decision between various construction methods, such as the decision between in-situ concrete construction and hybrid concrete construction. Hybrid concrete construction is a combination of pre-fabricated concrete and cast in-situ concrete to obtain the supreme benefits of their different construction qualities. This method of construction is ultimately used to achieve faster, and occasionally, more cost effective construction. Hybrid concrete construction, today, is a well-known term in the construction industry and is widely used in the UK and other developed countries. However, the use thereof is limited in South Africa, and in-situ concrete construction remains the conventional method of construction. Possible reasons for the limited use of hybrid concrete construction are investigated in this study. With the intent of improving the construction industry of South Africa, guidelines are provided to assist project teams in a decision between in-situ concrete construction and hybrid concrete construction. The decision between construction methods is based on many factors, such as project time, cost, quality, safety, environmental performance, socio-economic aspects (labour) and client satisfaction. Project time and cost are, however, the most important of these factors. It is stated that the structure of a building represents typically only 10 % of the construction cost, however, the choice of construction method and material can have significant effects on the cost of other elements throughout the life cycle of construction projects. It is therefore important to measure the whole life cycle cost when deciding between construction methods, such as in-situ concrete construction and hybrid concrete construction. The aim of this study is to identify and investigate the factors that influence project time and cost, throughout the life cycle of construction projects, and to provide a framework that can assist project teams in their decision between in-situ concrete construction and hybrid concrete construction in South Africa. The decision between these two construction methods is influenced by a vast number of variables that may be difficult to quantify. The framework therefore consists of qualitative information that can assist project teams in their decision. The framework provided in this study includes the factors that have an influence on the time and cost for a decision between in-situ concrete construction and hybrid concrete construction. These factors are identified for the three primary phases in the life cycle of construction projects. These phases are the design phase, the construction phase and the maintenance phase. / AFRIKAANSE OPSOMMING: Die konstruksiebedryf is 'n kompiterende mark en kontrakteurs moet op datum bly met nuwe konstruksie metodes en tegnologieë. In Suid-Afrika word daar van projek spanne vereis om vinnige besluite gedurende vroeë stadiums van 'n projek te neem. Hierdie besluite moet dikwels in 'n kort tydperk geneem word, en sluit die besluit tussen verskillende konstruksie metodes in, byvoorbeeld die besluit tussen in-situ en hibriede beton konstruksie. Hibriede beton konstruksie (HBK) is 'n kombinasie van in-situ en voorafvervaardigde beton elemente. HBK word in die algemeen gebruik om te baat uit 'n vinniger konstruksie tydperk, en kan soms ook ‘n meer koste-effektiewe metode van konstruksie wees. HBK word gesien as 'n bekende term in die konstruksiebedryf en word veral toegepas in ontwikkelde lande soos die VSA, Japan en Engeland. Die toepassing daarvan in Suid-Afrika is egter beperk. In Suid-Afrika word in-situ beton konstruksie nog steeds die meeste gebruik en staan dus bekend as die mees algemene metode van konstruksie. Hierdie studie ondersoek moontlike redes vir die beperkte gebruik van HBK in Suid-Afrika. Met die oog op 'n verbeterde konstruksiebedryf in Suid-Afrika, word rigylyne voorsien, wat projek spanne kan gebruik vir 'n besluit tussen in-situ en hibriede beton konstruksie. Daar is verskeie faktore wat 'n rol speel in die besluit tussen twee konstruksie metodes. Hierdie faktore sluit in, die tyd, koste, kwaliteit, veilighed, omgewings impak, sosio-ekonomiese aspekte (soos arbeid) en kliënt tevredenheid, van 'n projek. Tyd en koste is egter die belangrikste van hierdie faktore. Die metode waarvolgens 'n struktuur gebou word kan 'n beduidende uitwerking op die koste van ander elemente in die lewensiklus van 'n konstruksie projek hê. Dit is gevolglik belangrik om die hele lewensiklus koste in ag te neem wanneer daar besluit moet word tussen verskeie konstruksie metodes, soos in-situ en hibriede beton konstruksie. Die doel van hierdie studie is gevolglik om die faktore wat 'n invloed het op die tyd en lewensiklus koste van konstruksie projekte te identifiesieer. Hierdie faktore word dan gebruik om 'n raamwerk voor te stel. Projek spanne kan hierdie raamwerk gebruik as 'n riglyn om te besluit tussen in-situ en hibriede beton konstruksie. Die besluit tussen hierdie twee konstruksie metodes is afhanklik van 'n groot aantal veranderlikes, wat moeilik is om te kwantifiseer. Die raamwerk bestaan dus uit kwalitatiewe inligting wat projek spanne kan gebruik om 'n ingeligte besluit te neem oor in-situ en hibriede beton konstruksie. Die raamwerk wat in hierdie studie voorgestel word sluit dus die faktore in wat 'n invloed het op die tyd en koste vir 'n besluit tussen in-situ en hibriede beton konstruksie. Hierdie faktore is geïdentifiseer vir die drie primêre fases in die lewensiklus van 'n konstruksie projek. Hierdie fases is die ontwerp fase, die konstruksie fase en die onderhoud fase.

Höga byggkostnader och betydande bostadsbrist i Sverige visar att ett effektivare bostadsbyggande krävs. En reducering av slöseri i byggprocessen bidrar till en effektivisering av både tid och kostnad. För att öka förståelsen för vikten av effektivisering synliggör den här studien slöseri i produktionsflödet för en platsgjuten betongvägg i ett bostadsprojekt. Studien visar även var i produktionsflödet det finns förbättringsmöjligheter. Slöseriet synliggjordes genom en tidsstudie som visade på stor potential till förbättring i bostadsprojektets resursflöde, materialflöde och informationsflöde. Mycket tyder på att dessa brister i produktionsflödet beror på allt för kort byggtid, vilket leder till att en fullgod planering inte alltid utförs. / High construction costs and considerable housing shortages in Sweden show that a more efficient housing construction is required. A reduction of waste in the construction process contributes to the efficiency of both time and cost. In order to increase the understanding of the importance of efficiency, this study reveals waste in the production flow of a cast in-situ concrete wall in a housing project. The study also shows where in the production flow there are improvement opportunities. The waste was made visible through a time study which showed great potential for improvement in the housing project resource flow, material flow and information flow. There are many indications that these shortcomings in the production flow are due to a too short construction time, which means that a good planning is not always carried out.

Pour évaluer la résistance mécanique du béton dans un ouvrage existant, la méthodologie courante combine des mesures non destructives (CND) comme le rebond ou/et la vitesse des ondes ultrasoniques avec la technique destructive (carottes) afin de produire une relation‘‘modèle de conversion” entre la résistance mécanique et les mesures CND. Le modèle de conversion est utilisé pour estimer la valeur locale de résistance mécanique à chaque emplacement de test en utilisant la valeur CND correspondante. Ensuite, on calcule les estimations de la résistance moyenne et/ou de l’écart-type de la résistance (variabilité de la résistance du béton). Cependant, la fiabilité d’estimation est toujours discutable en raison des incertitudes associées à l’évaluation de la résistance basée sur les mesures CND. Pour améliorer la fiabilité, les incertitudes doivent être réduites en spécifiant et en contrôlant leurs facteurs d’influence. Par conséquent, l’objectif de cette thèse est d’analyser la méthodologie d’évaluation courante afin de fournir des recommandations pratiques qui peuvent améliorer la fiabilité de l’évaluation de la résistance in-situ du béton dans les ouvrages existantes par des tests non destructifs et des carottes.Pour ce but, un simulateur a été construit afin d’analyser les effets des facteurs les plus influents en utilisant une vaste campagne de données provenant de sources différentes (études in situ ou en laboratoire et données synthétiques générées). La première contribution de ce travail est le développement d’une nouvelle approche d’identification du modèle ‘‘bi-objectif” qui peut efficacement capturer la variabilité de la résistance mécanique en plus de la moyenne. Après avoir étudié l’effet du mode de sélection des emplacements pour les carottes, une méthode a été proposée pour sélectionner ces emplacements en fonction des mesures CND ‘‘sélection conditionnelle” qui améliore la qualité de l’évaluation sans coût supplémentaire. Une dernière innovation est l’établissement de courbes de risque qui quantifient la relation entre le nombre de carottes et la précision de l’estimation. Enfin, des recommandations ont été formulées afin de fournir des estimations plus fiables. / To assess concrete strength in an existing structure, the current methodology combines nondestructive measurements (NDT) like rebound hammer or/and pulse velocity with destructive technique (cores) in order to implement a relationship ‘‘conversion model” between the compressive strength and NDT measurements. The conversion model is used to estimate the local strength value at each test location using the corresponding NDT value.Then the estimated mean strength and/or estimated strength standard deviation (concrete strength variability) values are calculated. However, the reliability of these estimated values isalways a questionable issue because of the uncertainties associated with the strength assessment based upon NDT measurements. To improve the reliability, the uncertainties must be reduced by specifying and controlling their influencing factors. Therefore, the objective of this thesis is to analyze the current assessment methodology in order to provide practical recommendations that can improve the reliability of assessing the in-situ strength in existing concrete structures by nondestructive tests and cores.To this end, a simulator was built in order to analyze the effects of the most influencing factors using a large campaign of datasets from different sources (in-situ or laboratory studies,and generated synthetic data).The first contribution of this work is the development of a new model identification approach“bi-objective” that can efficiently capture the strength variability in addition to the mean strength. After studying the effect of the way of selection the core locations, a method was proposed to select these locations depending on the NDT measurements “conditional selection” that improves the quality of assessment without additional cost. A third innovation was the development of a procedure to identify the relation between the number of cores and the accuracy of the estimation. Finally recommendations were derived in order to providemore reliable estimated values.

Purpose: this degree project will examine the possibilities of increasing the structural integrity in case of fire of a preexisting concrete building according to the rules in EKS 11, specifically for a hospital building. Furthermore, the degree project will provide solutions to increase the structural integrity in case of fire. Method: the study is based on a technical report provided by Kadesjös Ingenjörsbyrå AB where information about the hospital buildings technical aspects is presented. To examine current rules for fire-resistance rating of the hospital building, the regulations presented in BBR and EKS 11 were studied. Products had to fulfill the criteria of the European testing standards when they were evaluated as solutions that would increase the structural integrity of the building. The products were then evaluated according to the criteria presented in Eurocode 2 when dimensioning with tabulated data. An interview were held with Michael Försth professor in structural and fire engineering. Professor Försth were asked questions to evaluate potential methods and products that could increase the fire-resistance rating of the hospital building. Results: showed that proposed solutions are able to increase the structural integrity in case of fire of the hospital building to a degree where they were able to fulfill the requirements. Not all solutions were appliable on all building components of the hospital buildings. The difference in technical aspects of the solutions were presented. Conclusions: the identified solutions for increasing the structural integrity in case of fire are rock wool insulation, fire protection paint, additional concrete casting on columns and installation of sprinkler system. The solutions differ in technical aspects such as the space they take when implemented, weight increase when implemented, the amount they increase the structural integrity in case of fire when implemented and the method of implementing the solutions.

The diploma project designs architectural study of Intensive Urban Housing in the city of Brno, district Veveří. Its proposed a building of complex form on vacant site desined by Veveří, Kounicova, Pekárenská and Sokolská Streets which used to be a military grounds. Intensive Urban Housing includes wide community amenities and dwelling for different social groups. As it is located on within walking distance to services which makes the complex self-sufficient, the transport demands are reduced. The proposal works with differentiation of public space, main buildings volumes and facade arrangement that create a lovely city environment and new atractive location in the city of Brno.