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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).

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.

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.

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.

Material-based computation has been recently introduced in architectural education, where parameters and rules related to materials are integrated into algorithmic thinking. The authors aim to identify affordances of material-based computation in terms of supporting the understanding of parametric design, informing the process of parametric form finding in an educational setup and augmenting student learning outcomes.

The authors propose a material-informed holistic systems design framework for parametric form finding. The authors develop a pedagogical approach that employs material-based computation focusing on the interplay between the physical and the digital in a parametrically driven façade design exercise. The approach comprises two phases: (1) enabling physical exploration with different materials to arrive at the design logic of a panel prototype and (2) deducing embedded and controlled parameters, based on the interplay of materials and deriving strategies for pattern propagation of the panel on a façade composition using variation and complexity.

The results confirmed the initial hypothesis, where the more explicit the material exploration and identification of physical rules and relations, the more nuanced the parametrically driven process, where students expressed a clear goal oriented generative logic and utilized parametric design to inform form finding as a bottom-up approach.

Most precedent approaches developed to teach parametric design concepts in architectural education have focused on universal strategies that often result in fixating students on following standard blindly followed scripts and procedures, thus defying the purpose of a bottom-up form finding framework. The approach expands the pedagogical strategies employed to address parametric design as a form finding process.

The purpose of this paper is to develop a framework to optimize time, cost and quality in a multi-mode resource-constrained project scheduling environment.

A case study approach identified the activity execution modes in building construction projects in India to support multi-mode resource-constrained project scheduling. The data required to compute time, cost and quality of each activity are compiled from real construction projects. A binary integer-programming model has been developed to perform multi-objective optimization and identify Pareto optimal solutions. The RR-PARETO3 algorithm was used to identify the best compromise trade-off solutions. The effectiveness of the proposed framework is demonstrated through sample case study projects.

Results show that good compromise solutions are obtained through multi-objective optimization of time, cost and quality.

Case study data sets were collected only from eight building construction projects in India.

It is feasible to adopt multi-objective optimization in practical construction projects using time, cost and quality as the objectives; Pareto surfaces help to quantify relationships among time, cost and quality. It is shown that cost can be reduced by increasing the duration, and quality can be improved only by increasing the cost.

The use of different activity execution modes compiled from multiple projects in optimization is illustrated, and good compromise solutions for the multi-mode resource-constrained project scheduling problems using multi-objective optimization are identified.

This paper aims to analyze on‐site production and sources of construction wastes through data obtained from a detailed questionnaire survey and structured interviews conducted in Shenzhen.

A questionnaire survey is conducted to investigate the compositions of these construction waste and their sources. One hundred and ten copies are sent to governmental officers, designers, engineers, and contractors, and 84 responses are received, in which the respondent rate is about 76.4 percent.

According to the survey results, concrete, cement, brick, timber, tile, steel, and aluminum wastes are the main waste sources produced on construction sites. The sources of these wastes are varied. Suggestions to improve the existing waste situation are also discussed.

Various types of construction wastes are generated during construction activities. Expansion of construction wastes not only represents an enormous dissipation of resources but also results in serious environmental pollution, thus creating negative effects to the sustainable development of environmental industry and society. With the developing of economy and industry, waste problems have become more serious in recent years; therefore, waste management is becoming a pressing issue.

This paper provides a comprehensive review of the literature concerning the various causes of failures of external wall tile finishes.

A 4×3 matrix hierarchy framework is developed for a systematic analysis of the literature reviewed.

The findings from this paper indicate the importance of environmental effects, movement joints, and adhesive on the performance of external wall tile finishes. Thermal and moisture effects induce movement of tiles, and the failure of the tiling system depends very much on the adhesive strength and the provision of movement joints. Workmanship is also a key factor affecting the performance of external wall tile finishes and should not be overlooked.

Various studies have been carried out on the causes of defects in external finishes in the past. However, many of them were case‐oriented and were not supported by laboratory findings. The hierarchical framework developed in this paper serves as a basis for further laboratory and field studies on this issue.

The framework is conducive to the diagnosis of external wall tile delamination.

This paper reviews systematically and comprehensively the literature on the causes of external wall tile delamination.

With a growing list of available materials and processes, the inherent mechanical and thermophysical properties of three-dimensional (3D) prints are important design targets. This paper aims to study the functionality of binder jet 3D printed objects for thermally activated building construction elements and recyclable formwork for concrete structures.

Binder jet printed sand samples with various material and post-processing parameters (infiltration and baking) are prepared and studied. Using a statistical experiment design, the mechanical (flexural and compressive strength) and thermal (conductivity and specific capacity) characteristics are quantified.

Relative to the unprocessed “green” print samples, post-processing improved the flexural and compressive strength of the samples by factors of 6.9 and 21.6, respectively; the thermal conductivity and specific heat capacity were improved by factors of 7.7 and 1.2, respectively. For the investigated temperature range (20°C–200°C), the “green” prints showed excellent stability while the stability of post-processed samples depended on the infiltrate used. Microscopic images of the microstructures offered evidence to support improvement in the mechanical and thermo-physical characteristics of the 3D printed sand elements.

The literature review concluded that optimal printing parameters and infiltration under vacuum could further improve the mechanical and thermo-physical properties of the binder jet printed elements. However, both these factors were not explored in this research. The statistical experimental design approach provided more flexibility to choose the number of experiments for a fixed amount of time and resources. However, for future work, a more extensive number of experiments and reproducibility testing for each combination of binder-infiltrate is recommended.

3D printing has been identified as a promising opportunity to reduce material usage and improve construction efficiency in the field of architecture and building engineering. The emerging fabrication technologies are further expected to significantly reduce the operational energy of buildings through performance integration, i.e. multi-functional building elements with integrated heat- and mass-transfer capabilities to replace conventional systems.

This study has quantified the impact of infiltration on the mechanical and thermo-physical characteristics of sand-printed elements and, as such, reports reproducible functional performance maps for sand-print applications. The research demonstrates a way to achieve the desired functional characteristics of 3D prints through combinations of material selection and process/post-processing parameters.

The objective is to address the major issues and suggest solutions to solve the water seepage and health related problems in residential buildings.

The methodology relies on a literature review on water damage in residential buildings with references to the vertical spread of SARS in a housing estate in Hong Kong. Working procedures for handling seepage complaints by Hong Kong government departments and their performance are examined.

The study found that individual departments have difficulties in identifying: the cause and source of seepage, and resolutions to the problem given the limited powers and legal constraints that exist. A holistic approach by individual departments is needed to address the issue. The proposed formation of Owners' Corporations, third party insurance and repair and maintenance sinking fund for old buildings would help solve the building defect and health related problems.

The suggestions in the study would help reduce and partly prevent the environmental nuisance and, more importantly, health risk. Residents are better prepared in the future for a possible return of SARS or other infectious disease.

Research on water damage is very scarce in Hong Kong. And perhaps this is the first of its kind. The study identifies the broader issue of maintaining and managing a high‐rise residential building. The building management and health related problems identified in the study should be noted in any policy addressing housing and health issues.

The purpose of this paper is to analyze energy performance of the multi-storey buildings built in the city of Tlemcen between 1872 and 2016.

A diagnosis based on a bottom-up methodology, using statistical techniques and engineering, has been developed and applied. To do this, demand condition analysis was conducted using a data collection survey on a sample of 100 case studies. Physical characteristics of the buildings have been determined through the archetype by period. This serves to define the strengths and weaknesses of buildings as energy consumers.

The obtained results showed that dwellings built between 1872 and 1920 offer better energy performance with a consumption index close to 130kWh/m²/year and this compared to the five periods considered. For dwellings built between 1974 and 1989, energy consumption is higher with an index approaching 300kWh/m²/year, thus qualifying the buildings of this period as energy intensive.

A database is established to collect physical information on the existing housing stock and thus allow their classification vis-à-vis of the energy label. This study is part of a research project aimed at evaluating and determining optimal measures for energy rehabilitation of multi-family buildings in Tlemcen. Thermal rehabilitation solutions are proposed using thermal simulations, in the following studies, to improve thermal performance of existing buildings. This study constitutes the first step of a roadmap applicable to other cities constituting climatic zones in Algeria. This helps to enrich the Algerian thermal regulation in thermal rehabilitation of existing residential buildings and conception of new ones, in urban areas with a similar climate.

The purpose of this paper is to present a case report involving environmental performance analysis of a small Brazilian business from the foundry industry.

An environmental performance indicator was developed (I_epa) which is calculated taking into consideration the weighting of potential environmental impacts of each residue/sub product generated, the relative spatial dispersion which each residue/sub product can reach, and the adequacy evaluation of final allocation accomplished by the company for each residue/sub product.

Despite the evidence that the corporation do not conduct washing of gases emitted from the chimney of the foundry furnace, which consists an environmentally inadequate attitude, the result of I_epa=97.50 percent was obtained. This favorable result is due to the adequate allocation given to residues generated in greater volume in the process, the molding sand. This sand is addressed to an industrial landfill, which is an environmentally adequate practice and approved by competent environmental authorities.

The method used can be applied to measure the environmental impact generated by any business of the foundry sector industry.

The originality of the work is in the developed method, which takes into account: the potential impact of each residue/sub product generated, the amount of each residue/sub product generated in a given time period, the dispersion that each residue/sub product can attain, and the evaluation of eventual allocation of each residue/sub product.

Earthen construction does not meet today’s requirements due to certain limitations such as low water resistance and its high vulnerability to cracking damage. The purpose of this study is to improve the mechanical properties and low durability of adobe blocks by incorporating date palm wastes as a natural reinforcement and lime as a stabilizer.

Soil from the region of Biskra in Algeria was mixed with sand and lime in suitable ratios. Then, date palm wastes were added to the previous mixture at different ratios (0.3%, 0.6% and 0.9%) by dry mix weight to manufacture adobes. Cubical and cylindrical specimens were prepared and tested in a laboratory to investigate the curing time, mechanical and durability characteristics of the formulated blocks. In addition, X-ray diffraction and scanning electron microscopy (SEM) tests were used to identify the materials.

It has been observed that the addition of lime to the soil is very beneficial for its stabilization, in particular for an optimum of 12%. The presence of date palm waste in the mixture (soil + lime) generated a significant improvement in tensile strength reaching a rate of about 67%. The same observation was made for the tests of resistance to dry abrasion, resistance to erosion, attack by external sulphate and wetting/drying. However, for cases of compressive strength, water absorption and swelling an unfavorable effect was recorded.

Based on the above-mentioned findings, this paper presents a novel solution to increase the durability of adobe materials using date palm wastes with oven curing at 65°C for about nine days. Adopting such an approach would certainly encourage building durable mud housing on a large scale. This can contribute to solving the acute housing shortage, particularly in poor countries.