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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.

This paper aims to investigate the bond strength of metakaolin-based geopolymer mortar with cement mortar.

The mortar-mortar bond strength is assessed by slant shear and split tensile tests; pure shear strength is evaluated by Mohr’s criterion for result validation. Metakaolin-based geopolymer mortar is cast over the cured cement mortar specimen with two levels of surface roughness: smooth or grooved interface. The influence of the alkaline solution to metakaolin ratio on geopolymer bond strength is studied. Compressive strength, ultrasonic pulse velocity, permeability and flow table tests are also performed.

The paper’s findings are highlighted as follows: (1) strong mortar-mortar bond properties achieved for geopolymer mortar in all tests and conditions and validated by Mohr’s criterion and pure shear, (2) a lower alkaline solution to metakaolin ratio achieves higher bond strength to Portland cement mortar and (3) geopolymer mortar has higher compressive strength and ultrasonic pulse velocity than cement mortar at all curing ages; additionally, it is more flowable and less permeable.

The full replacement of Portland cement with metakaolin, a more sustainable cementitious material, will contribute to the decarbonization of the construction industry.

Limited research has been carried out on the bond strength of metakaolin-based geopolymer mortar to Portland cement mortar. Also, computing the pure shear using Mohr’s circle criterion of metakaolin-based geopolymer to validate the results can be considered original.

The first paper, entitled “The perception of tenants in the refurbishment of tower blocks” (Facilities, Vol. 31, No. 3/4), argued that refurbishment was the best option that a local authority could undertake to improve tower blocks. The study also found that refurbishment maintained local communities by keeping families together and sustained the environment. This paper aims to present and examine similar views from the contractor's and landlord's representatives on several aspects affecting the refurbishment process

A literature review is used to identify the perceived problems and benefits of refurbishment. A qualitative approach comprising semi structured interviews and questionnaires was used to collect data from three contractors or service providers of the refurbishment process and two landlords' representatives, namely the clerk of works drawn from the housing association. The sample data are analysed using frequency analysis and content analysis.

Refurbishment as opposed to demolition was identified as a viable option for achieving sustainability. There were some divergent views among the respondents concerning the achievements to be gained from refurbishments. The project managers identified “client satisfaction”, and “within budget and time”. The senior site manager chose “a better way of life” and “improved security”. The quantity surveyor opted for “profit‐oriented”, finally, “provision of decent homes at affordable prices” was identified by the senior clerk of works. The knowledge of the council funding mechanisms for refurbishment works among the respondents ranged from adequate to ideal. The contractor's representatives exhibited limited knowledge.

The findings of the study provide practical value for contractor's and landlord's (housing association) representatives within the construction industry confronted with the decision of whether to undertake some refurbishment works. Some lessons learned could also improve the housing stock or asset management strategies for the landlord's representatives.

The paper is original in the sense that it identifies how the contractor's and landlord's (housing association) representatives as drawn from different professional background rate the reasons, benefits, and practicalities of undertaking refurbishment works of tower blocks or high rise buildings. The study also provides some insights on the contractor's and landlord's (housing association) representative's knowledge and awareness of sustainable development, and councils' funding mechanisms for undertaking refurbishment works.

Refurbishment has been suggested as a means towards sustainable development. The paper seeks to examine the tenants' perception on the benefits, effectiveness and overall satisfaction with the refurbishment process of the tower blocks.

Literature review is used to identify the perceived problems, benefits and overall process of refurbishment. A survey questionnaire was used to collect data from 67 tenants living in three tower blocks (high‐rise flats) in West London. The sample data are analysed using descriptive statistics such as frequencies including ranking analysis.

The findings suggest that refurbishment as opposed to demolition was a viable option for achieving sustainability. The majority of the tenants agreed that their surroundings and way of life improved after refurbishment. Other notable benefits from refurbishment were improved security, improved social behaviour and social harmony. However, the respondents failed to either identify or suggest future refurbishment works that could improve their estates. Lack of consultation between the service providers and contractors with the tenants was identified as the major barrier affecting the future refurbishment.

The cross‐sectional data made it difficult to generalise the findings.

The paper identifies the benefits and roles of refurbishment in the context of its contribution to sustainability. It is argued that there is a need for early and systematic involvement of tenants or occupants in order to facilitate the refurbishment process as a vehicle for attaining sustainability principles.

The paper contributes to empirical research on major benefits and problems of refurbishment when viewed from the tenant's perspective. It also demonstrates how the refurbishment process can be used as a vehicle for achieving sustainability outcomes.

The purpose of this paper is to concern with using municipal solid waste incineration bottom ash (MSWI-BA) in concrete application.

In this paper, the performance of reinforced concrete (RC) beams containing MSWI-BA was investigated. Four concrete mixes were used in this study. The control mix had a proportion of 1 (cement): 2 (fine aggregates): 4 (coarse aggregates) by weight. In the other three mixes, the fine aggregates were partially replaced with 20%, 40% and 60% MSWI-BA (by weight). The water to cement ratio was kept constant at 0.5 in all mixes. Concrete cubes and cylinders were prepared to determine some physical and mechanical properties of concrete, whereas RC beams were used for determining the structural performance.

There was an increase in compressive strength, tensile strength and the modulus of elasticity when 20% of fine aggregates were replaced with MSWI-BA. However, beyond 20% these properties were reduced. The load bearing capacity and deflection were the highest for the control beam and the beam with 20% MSWI-BA.

The research conducted in this investigation used a specific type of MSWI-BA. The composition of the waste can vary from one plant to another and this presents one of the limitations.

The findings of this research indicate that MSWI-BA can partially substitute fine aggregate, thus reducing the impact of construction on the environment.

The MSWI-BA used in this research differs from other types as the waste papers and cartons are removed from the waste and used to produce other products. Therefore, this study is considered original as it examines MSWI-BA with different properties for use in construction.

The purpose of this paper is to provide a systematic and comprehensive review of the existing literature on the determinants of firms reporting practices.

Following a systematic method, the sample literature of 135 studies was collected from the Scopus database. These studies were evaluated in terms of the theoretical lenses applied in the literature, yearly trend, regional distribution, research settings and prior studies finding to provide some recommendations for further research.

The investigation revealed that the literature was more interested in the agency theory in investigating the drivers of voluntary reporting such as company size, age, leverage, liquidity, profitability, corporate governance and ownership structure. Although firm-specific determinants were the most examined in the previous studies, however, the result is still inconclusive. Also, limited work was found on the country-related factors, while internal audit impact has yet to be explored.

Being the first of its kind, this research provides a comprehensive review of the current research landscape on the drivers of environmental or social disclosure and highlights several interesting opportunities for future research.

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 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 Islamic world spans many different languages with different language structures. This paper aims to explore one way in which language structure affects consumer response to the marketing of cobrands.

Two between subject experiments were conducted using samples of participants from Saudi Arabia and the USA. The first manipulated partner brand category similarity and brand name order, along with the structure of the language used to communicate with the market. The data for this study includes Arabic speakers in Saudi Arabia as well as English speakers in the USA. The second study explores how targeting a population fluent in multiple languages of varied structure nullifies the findings from the first study and uses Latino participants in the USA.

This study finds that when brands come from similar product categories, name order did not affect cobrand evaluations, but it did when the brands come from dissimilar product categories. Here, evaluations of the cobrand are enhanced when the invited brand is in the position that adjectives occupy in the participant’s language. The authors also find that being proficient in two languages, each with a different default order for adjectives and nouns, quashes the effect of name order otherwise seen when brands from dissimilar product categories engage in cobranding.

By examining the impact of language structure on the effects of cobrand evaluation and conducting studies among participants with differing dominant languages, this research can rule out simple primacy or recency effects.

The recent Middle East war and the subsequent strengthening of political ties between the United States and Middle Eastern countries have opened the doors to attractive business opportunities and increased the chance for the transferability of Western business practices more than ever before. The objectives of this study were to examine marketing practices among Egyptian firms. The results from 51 firms operating in various sectors of the Egyptian economy indicate a massive neglect and absence of modern marketing practices among the surveyed firms. Foreign firms that adapt their strategies to cultural and structural impediments to marketing in that country will prove most profitable.