Workers are an important factor in the implementation of a construction project. Applying ergonomic postures for workers in the projects is necessary to minimize the risk of work accidents and the risk of experiencing musculoskeletal disorders (MsDs). The use of lightweight brick for wall construction is relatively new and is in great demand by construction industries in Indonesia. During wall construction, workers do repetitive activities such as bending, kneeling, holding tools, or tilting the body. These activities potentially increase the risk of injury and musculoskeletal disorders. This study aims to assess the work posture of workers on the wall construction using lightweight brick and to analyze the high-risk activities. The wall construction work assessment included five stages of activities, (1) material transfer, (2) practical columns making and installation, (3) lightweight brick adhesive dough-making process, (4) lightweight bricks laying, and (5) lightweight brick plaster. The Rapid Upper Limb Assessment (RULA) method was used to evaluate the working posture. This method was developed to investigate the risk of abnormalities that workers will potentially experience. Based on the RULA employee assessment worksheet, the research results showed that 69% of workers have a high-risk level of work posture and 31% have low-risk levels of work posture. There are three activities with a high-risk level, namely, material transfer, lightweight brick laying, and lightweight brick plaster. At the same time, practical column making and installation work and lightweight brick adhesive dough-making processes are at a low-risk level. According to the RULA risk level, action is required to investigate and immediately improve activities with a high-risk level. If workers continue to work with the same posture, they will be at risk of developing musculoskeletal disorders related to the neck, trunk, and wrists in the near future. Correcting the worker’s posture can be done by improving work position, process, and workplace layout.
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The seismic assessment of unreinforced masonry (URM) buildings with cavity walls is of high relevance in regions such as in Central and Northern Europe, Australia, New Zealand and China because of the characteristics of the masonry building stock. A cavity wall consists of two separate parallel walls usually connected by metal ties. Cavity walls are particularly vulnerable to earthquakes, as the out-of-plane capacity of each individual leaf is significantly smaller than the one of an equivalent solid wall. This paper presents the results of an experimental campaign conducted by the authors on metal wall tie connections and proposes a mechanical model to predict the cyclic behaviour of these connections. The model has been calibrated by us- ing the experimental results in terms of observed failure modes and force-displacement responses. Results are also presented in statistical format.
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The assessment of the out-of-plane response of unreinforced masonry (URM) buildings with cavity walls has been a popular topic in regions such as Central and Northern Europe, Australia, New Zealand, China and several other countries.Cavity walls are particularly vulnerable as the out-of-plane capacity of each individual leaf is significantly smaller than the one of a solid wall. In the Netherlands, cavity walls are characterized by an inner load-bearing leaf of calcium silicate bricks, and by an outer veneer of clay bricks that has only aesthetic and insulation functions. The two leaves are typically connected by means of metallic ties. This paper utilizes the results of an experimental campaign conducted by the authors to calibrate a hysteretic model that represents the axial cyclic response of cavity wall tie connections. The proposednumerical model uses zero-length elements implemented in OpenSees with the Pinching4 constitutive model to account for the compression-tension cyclic behaviour of the ties. The numerical model is able to capture important aspects of the tie response such as the strength degradation, the unloading stiffness degradation and the pinching behaviour. The numerical modelling approach in this paper can be easily adopted by practitioner engineers who aim to model the wall ties more accurately when assessing the structures against earthquakes.
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The postdoc candidate, Giuliana Scuderi, will strengthen the connection between the research group Biobased Buildings (BB), (collaboration between Avans University of Applied Sciences and HZ University of Applied Sciences (HZ), and the Civil Engineering bachelor programme (CE) of HZ. The proposed research aims at deepening the knowledge about the mechanical properties of biobased materials for the application in the structural and infrastructural sectors. The research is relevant for the professional field, which is looking for safe and sustainable alternatives to traditional building materials (such as lignin asphalt, biobased panels for bridge constructions, etc.). The study of the mechanical behaviour of traditional materials (such as concrete and steel) is already part of the CE curriculum, but the ambition of this postdoc is that also BB principles are applied and visible. Therefore, from the first year of the programme, the postdoc will develop a biobased material science line and will facilitate applied research experiences for students, in collaboration with engineering and architectural companies, material producers and governmental bodies. Consequently, a new generation of environmentally sensitive civil engineers could be trained, as the labour market requires. The subject is broad and relevant for the future of our built environment, with possible connections with other fields of study, such as Architecture, Engineering, Economics and Chemistry. The project is also relevant for the National Science Agenda (NWA), being a crossover between the routes “Materialen – Made in Holland” and “Circulaire economie en grondstoffenefficiëntie”. The final products will be ready-to-use guidelines for the applications of biobased materials, a portfolio of applications and examples, and a new continuous learning line about biobased material science within the CE curriculum. The postdoc will be mentored and supervised by the Lector of the research group and by the study programme coordinator. The personnel policy and job function series of HZ facilitates the development opportunity.
A transition to a circular economy is needed to revolutionize the construction sector and make it more sustainable for present and future generations. While the construction industry and the production of construction materials contribute to environmental pollution, they also offer great potential for addressing many environmental problems. Sheet materials are engineered wood boards that are produced from recycled or solid wood where an adhesive is used to bind the particles together, predominantly used in: Furniture manufacturing, Flooring application, Roofing, Wall sheathing. The most common binder for boards is urea-formaldehyde. Other binders may be used depending on the grade of board and its intended end-use. For example, melamine urea-formaldehyde, phenolic resins and polymeric diphenylmethane diisocyanate (PMDI) are generally used in boards that require improved moisture resistance. Formaldehyde is classified in the in the European Union as a carcinogen and it carries the hazard statement 'suspected of causing cancer'. In this project mycelium composites are developed as a formaldehyde-free, fully natural and biodegradable material with high potential to substitute these hazardous materials. The heat-press process, the feasibility of which was evaluated in a previous Kiem HBO project, is to be further developed towards a process where mycelium sheets with different thicknesses will be obtained. This is considered as a fundamental step to increase the material approachability to the market. Different Material manufacturing techniques are also considered to enable the increase of sample thicknesses and volume. Moreover, a business study will be incorporated to allow further understanding of the material market potential. The consortium composition of V8 Architects, QbiQ, Fairm, Verbruggen Paddestoelen BV, and CoEBBE merges different expertise and guarantees the consideration of the whole material production chain. The research will contribute to bring mycelium composites a step closer to the market, giving them visibility and increasing the possibility to a commercial breakthrough.
Aerogel fibers consist of up to 99.9% of air which leads to outstanding insulation proper-ties for e.g. house construction. The simple use of aerogel fibers as wallpaper could lead to 25% energy savings. According to calculations of Advanced Manufacturing Office, energy savings of 1% saves 7500 million gallons of gasoline every year in the USA which equals, depending on the oil price, more than 18 billon USD. In this KIEM project, the cellulose purity needed to be able to spin cellulose into a fila-ment for aerogel production will be determined. Cellulose is the most abundant polymer on the planet. In principle, cellulose-based aerogels could replace petroleum-based and partly toxic polystyrene which is currently used for insulation purposes and which leads to toxic waste. The cellulosic starting material is generated via the “Beta process” as developed by a company called DSD. The “Beta process” offers an efficient way of generating ethanol from sugar beets. The by-product of that process contains cellulose, pectines and hemi-cellulose. To be able to use this mixture for wet spinning, this mixture needs to be puri-fied. Researchers and students from Zuyd University of Applied Sciences will, in collabora-tion with DSD, pursue the purification of the waste stream material in the labs of the Centre of Expertise CHILL. Next, the obtained cellulose grades will be processed as spinning dope in a wet spinning process on lab scale with up to 60 ml per batch at AMI-BM. The results will be used as feedback for the purification process. Several possible partners such as DSD, ACRRES (Application Center for Renewable Resources), Technoforce (extraction), Greenfields (fermentation) and VAM (washing in-stallations) show high interest for the up-scaling of the process and for the validation and implementation in the built environment, showing the feasibility a follow-up project.
