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The purpose of this paper is to check the feasibility of using biomaterial such as of Phragmites-Australis (PA) in cement paste to achieve sustainable building materials.

In this study, cement pastes were prepared by adding locally produced PA fibers in four different volumes: 0%, 0.5%, 1% and 2% for a duration of 180 days. Bottles and prisms were subjected to chemical shrinkage (CS), drying shrinkage (DS), autogenous shrinkage (AS) and expansion tests. Besides, prism specimens were tested for flexural strength and compressive strength. Furthermore, a mathematical model was proposed to determine the variation length change as function of time.

The experimental findings showed that the mechanical properties of cement paste were significantly improved by the addition of 1% PA fiber compared to other PA mixes. The effect of increasing the % of PA fibers reduces the CS, AS, DS and expansion of cement paste. For example, the addition of 2% PA fibers reduces the CS, expansion, AS and DS at 180 days by 36%, 20%, 13% and 10%, respectively compared to the control mix. The proposed nonlinear model fit to the experimental data is appropriate with R2 values above 0.92. There seems to be a strong positive linear correlation between CS and AS/DS with R2 above 0.95. However, there exists a negative linear correlation between CS and expansion.

The PA used in this study was obtained from one specific location. This can exhibit a limitation as soil type may affect PA properties. Also, one method was used to treat the PA fibers.

The utilization of PA fibers in paste may well reduce the formation of cracks and limit its propagation, thus using a biomaterial such as PA in cementitious systems can be an environmentally friendly option as it will make good use of the waste generated and enhance local employment, thereby contributing toward sustainable development.

To the authors best knowledge, there is hardly any research on the effect of PA on the volume stability of cement paste. Therefore, the research outputs are considered to be original.

The purpose of this paper is to examine the use of phragmites australis ash (PAA) in cementitious systems to achieve sustainable construction.

In this paper, the properties of mortar containing PAA as partial cement replacement are determined. The PAA is produced through slow burning in a closed system to minimize the CO₂ emission. A total of four mortar mixes are prepared with PAA replacement levels ranging from 0% to 30% by weight. The water to binder and the proportions of binder to sand are 0.55 and 1:3 by weight, respectively. The properties tested are density, compressive strength, flexural strength, ultrasonic pulse velocity, water absorption by total immersion and capillary rise. Testing is conducted at 1, 7, 28 and 90 days.

While there is a decrease in strength as the amount of PAA increases, there is strong indication of pozzolanic reaction in the presence of PAA. This is in agreement with the results reported by Salvo et al. (2015), where they found noticeable pozzolanic activities in the presence of straw ash, which is rich in SiO₂ and relatively high K₂O content. At 90 days of curing, there is a decrease of 5% in compressive strength at 10% PAA replacement. However, at 20% and 30% replacement, the reduction in compressive strength is 23% and 32%, respectively. The trend in flexural strength and ultrasonic pulse velocity is similar to that in compressive strength. The water absorption by total immersion and capillary rise tends to increase with increasing amounts of PAA in the mix. There seems to be a linear relationship between water absorption and compressive strength at each curing age.

The Phragmites australis plant used in this investigation is obtained from one location and this present a limitation as the type of soil may change the properties. Also one method of slow burning is used. Different burning methods may alter the composition of the PAA.

This outcome of this research will contribute towards sustainable development as it will make use of the waste generated, reduce the amount of energy-intensive cement used in construction and help generate local employment in the area where the Phragmites australis plant grows.

To the best knowledge of the authors, the ash from the Phragmites australis plant has not been used in cementitious system and this research can be considered original as it examines the properties of mortar containing PAA. Also, the process of burning in a closed system using this material.

The purpose of this study is to use waste materials in construction to create sustainable practices. This will contribute towards circular economy which has gained momentum in recent years throughout the world.

Waste materials cause enormous environmental problems that can have an adverse effect on the environment. Recycling of waste consists an important part of the circular economy. Therefore, researchers have been investigating the economic use of a variety of waste materials for reducing their environmental impact. One potential usage is in road subbase fill materials where wastes can be incorporated in large quantities. In this study, the engineering properties of road subbase fill materials (i.e. kaolinite) mixed with Granite Waste (GW), coal Fly Ash (FA) and lime are investigated. Kaolinite was replaced with 15% lime and FA, whereas the GW replacement varied from 10% to 20%. Testing included strength of the various soil compositions subjected to different curing times. Also the microstructural analyses and phase changes of samples were conducted using scanning electron microscopy and x-ray diffraction techniques, respectively. The results obtained indicate that GW can be incorporated in road base materials to improve its bearing capacity. The mixture consisting of 15% lime, 15% FA, 20% GW and 50% kaolinite resulted in maximum dry unit weight and optimum moisture content. Using GW exhibited a noticeable increase in the California Bearing Ratio of more than eight times at 1 day and 28 days curing regime compared with the control sample.

This study shows that GW and FA can be used for road subbase materials and can contribute toward a better and cleaner environment.

In this study, the engineering properties of road subbase fill materials (i.e. kaolinite) mixed with GW, coal FA and lime are investigated. This are value added in circular economy.

The use of waste polyethylene terephthalate (PET) plastics derived from shredded bottles in concrete is not formalized yet, especially in reinforced members such as beams and columns. The disposal of plastic wastes in concrete is a viable alternative to manage those wastes while minimizing the environmental impacts associated to recycling, carbon dioxide emissions and energy consumption.

This paper evaluates the suitability of 2D deterministic and stochastic finite element (FE) modeling to predict the shear strength behavior of reinforced concrete (RC) beams without stirrups. Different concrete mixtures prepared with 1.5%–4.5% PET additions, by volume, are investigated.

Test results showed that the deterministic and stochastic FE approaches are accurate to assess the maximum load of RC beams at failure and corresponding midspan deflection. However, the crack patterns observed experimentally during the different stages of loading can only be reproduced using the stochastic FE approach. This later method accounts for the concrete heterogeneity due to PET additions, allowing a statistical simulation of the effect of mechanical properties (i.e. compressive strength, tensile strength and Young’s modulus) on the output FE parameters.

Data presented in this paper can be of interest to civil and structural engineers, aiming to predict the failure mechanisms of RC beams containing plastic wastes, while minimizing the experimental time and resources needed to estimate the variability effect of concrete properties on the performance of such structures.

This study aims to generalize the research findings about the impact of individualism-collectivism, ethical idealism and inter-personal trust on ethically questionable negotiation tactics, such as pretending, deceiving and lying, in a Germanic culture, namely, that of Austria.

Survey questionnaires translated from English to German were collected from 304 respondents. A regression analysis was used to test the contribution of the independent variables to the explanation of negotiators’ attitudes towards questionable negotiation tactics.

The research empirically corroborated a classification of three groups of negotiation tactics, namely, pretending, deceiving and lying, in Austria. Austrian negotiators who scored high on vertical individualism tended to score high on the endorsement of the pretending tactic; those who scored high on horizontal collectivism tended to score low on the endorsement of the deceiving and lying tactics; those who scored high on vertical collectivism tended to score high on the endorsement of the deceiving and lying tactics; and those who scored high on inter-personal trust tended to score low on the endorsement of the pretending negotiation tactic. Idealistic negotiators tended not to endorse the use of pretending, deceiving and lying negotiation tactics.

The study investigated the respondents’ perceptions, rather than their actual negotiation behavior. Findings are limited to Germanic culture.

The study provides negotiators in Austria with a tool that has the potential to predict the extent to which Austrian negotiators would use various ethically questionable negotiation tactics.

This is the first study to present a model of the antecedents of negotiation tactics in a Germanic cultural context, where negotiation studies are limited. This study validates in Austria three questionable negotiation tactics groups of varying severity, which had previously been studied only in non-Germanic cultures. This research significantly contributes to the generalization of a model of the antecedents of the endorsement of questionable tactics across cultures.

The purpose of this paper is to examine the impact of individualism‐collectivism, trust, and ethical ideology on ethically questionable negotiation tactics, such as pretending, deceiving and lying, in Turkey.

Survey questionnaires translated from English to Turkish were administered to 400 respondents, of whom 379 fully completed the questionnaires.

The research empirically corroborated a classification of three groups of negotiation tactics, namely, pretending, deceiving and lying. Turkish negotiators who scored high on horizontal individualism tended to score highly on pretending and deceiving and less on lying, and presented an inverse relationship between scores on those tactics and score on idealism. Trust was not found to be related to any of the negotiation tactics.

The study investigated the respondents' perceptions rather than their actual negotiation behavior. The sample size, though large and inclusive of public and private sector employees, provided limited ability to generalize Turkish negotiator conduct.

The study provides hints to managers negotiating in Turkey of the extent to which Turkish managers would employ ethically questionable negotiation tactics.

This empirical field research is the first to present a model of the antecedents of negotiation tactics in Turkey, a country where negotiation studies are limited and are mostly conducted within the safe controls of the laboratory.

This paper presents the effects of replacing fine aggregate (FA) with waste foundry sand (WFS) in natural aggregate and construction waste aggregate concrete specimens without and with superplasticizer (SP), silica fume (SF) and fiber (F) to solve the disposal problems of various wastes along with saving the environment. This study aims to investigate the effect of construction waste, WFS along with additives on the stress-strain behavior and development of compressive strength with age.

The various concrete specimen were prepared in mix proportion of 1: 2: 4 (cement (C): sand: coarse aggregate). The water-cement ratio of 0.5 (decreased by 10% for samples containing SP) to grading 1: 2: 4 under air-dry condition was adopted in the preparation of concrete specimens. The compressive strength of various concrete specimen were noticed for 3, 7 and 28 days by applying load through universal testing machine.

Upon adding construction and demolition waste aggregates, the compressive strength of concrete after 28 days was comparable to that of the control concrete specimen. An enhancement in the value of compressive strength is perceived when FA is replaced with WFS to the extent of 10%, 20% and 30%. If both construction and demolition waste aggregate and WFS replacing FA are used, the compressive strength increases. When FA is interchanged with WFS in natural aggregate or construction demolition waste aggregate concrete including usage of SF or F, the compressive strength improves significantly. Further, when construction and demolition waste aggregate and WFS replacing FA including SP are used, the compressive strength improves marginally compared to that of control specimen. The rate of strength development with age is observed to follow similar trend as in control concrete specimen. Therefore, construction and demolition waste and or WFS can be used effectively in concrete confirming an improvement in strength.

The utilization of these wastes in concrete will resolve the problem of their disposal and save the environment.

This study aims to empirically validate five propositions about the benefits of three-dimensional (3D) visualizations for the management of subsurface utility projects. Specifically, the authors validate whether benefits from 3D in the literature of building construction project management also apply to subsurface utility projects and map them using a taxonomy of project complexity levels.

A multiple case study of three utility construction projects was carried out during which the first author was involved in the daily work practices at a utility contractor. 3D visualizations of existing project models were developed, and design and construction meetings were conducted. Practitioners' interactions with and reflections on these 3D visualizations were noted. Observational data from the three project types were matched with the five propositions to determine where benefits of 3D visualizations manifested themselves.

Practitioners found that 3D visualizations had most merit in crowded urban environments when constructing rigid pipelines. All propositions were validated and evaluated as beneficial in subsurface utility projects of complexity level C3. It is shown that in urban projects with rigid pipelines (project with the highest complexity level), 3D visualization prevents misunderstanding or misinterpretations and increases efficiency of coordination. It is recommended to implement 3D visualization approaches in such complex projects

There is only limited evidence on the value 3D visualizations in managing utility projects. This study contributes rich empirical evidence on this value based on a six-month observation period at a subsurface contractor. Their merit was assessed by associating 3D approaches with project complexity levels, which may help utility contractors in strategically implementing 3D applications.

The purpose of this research is to evaluate construction and industrial waste materials in concrete using different additives.

The experimental study investigated the effect of waste foundry sand (WFS), waste glass (GW) as partial substituent to natural sand and addition of waste glass fibers (GFs) and silica fume (SF) in natural/construction waste aggregate concrete on mechanical properties, durability and microstructure using.

The results reveal significant strength enhancement on using two admixtures, the maximum increase in compressive strength was obtained on using 20% WFS and 0.75% GF for both natural (75% increment) and construction waste (72% increment) coarse aggregates. Using three admixtures simultaneously, the maximum enhancement in compressive strength was found for (WFS(20%) + GW(10%) + GF(0.75%)) for both natural aggregates (122% increment) and construction waste (114% increment) coarse aggregates as compared to control mix. The 28 days split tensile and flexural strength of natural/construction waste aggregate concrete improve with age appreciably for optimal contents of single, two or three admixtures and the maximum tensile and flexural strength increment was 135 and 97% for mix (WFS(20%) + GW(10%) + GF(0.75%)) with natural aggregates as compared to control mix. The microstructural analysis results indicate improved microstructure upon partial substitution of sand with WFS, GW and SF along with addition of waste GFs.

The use of construction and industrial waste as a substituent to natural aggregate/sand will provide far reaching benefits for the green construction and the environment at large.

High rate of accidents continue to plague the construction industry. The advancements in safety technologies can ameliorate construction health and safety (H&S). This paper aims to explore the use of emerging technologies as an effective solution for improving safety in construction projects.

Following a detailed literature review, a questionnaire survey was developed encompassing ten technologies for safety management and ten safety enablers using technologies in construction. A total of 133 responses were gathered from Malaysian construction practitioners. The collected quantitative data were subjected to descriptive and inferential statistical analyses to determine the meaningful relationships between the variables.

Findings revealed that the most effective emerging technologies for safety management are: building information modelling (BIM), wearable safety technologies and robotics and automation (R&A). The leading safety enablers are related to improve hazard identification, reinforce safety planning, enhance safety inspection, enhance safety monitoring and supervision and raise safety awareness.

Safety is immensely essential in transforming the construction industry into a robustly developed industry with high safety and quality standards. The adoption of safety technologies in construction projects can drive the industry towards the path of Construction 4.0.

The construction industry has historically been slow to adopt new technology. This study contributes to advancing the body of knowledge in the area of incorporating emerging technologies to further construction safety science and management in the context of the developing world. By taking cognisance of the pertinent emerging technologies for safety management and the safety enablers involved, construction safety can be enhanced using integrated technological solutions.