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The construction industry had approached a critical limit which led to the increase of cement production. The production of cement would cause a broader environmental implication. Cement production is a major source of carbon dioxide emission. Carbon dioxide gas contributes about 63.33% of global warming since the production of one ton of cement would emit about one ton of carbon dioxide to the environment. To mitigate this issue, the research community has investigated the use of waste materials that possess similar chemical properties with cement content as a material for partial cement replacement. The use of rice husk ash has shown to be a contending candidate in the literature. Therefore, this paper attempts at reviewing the performance of rice husk ash as partial cement replacement. It could be observed from the literature that concrete with 5% up to 15% of rice husk ash showed an equivalent performance to ordinary concrete in compressive, flexural, and tensile strength. Thus, rice husk ash can be used as a material replacement in concrete and reduces pollution that originates from cement production and open burning of rice husk.

The construction industry uses a large amount of natural virgin material for differentgeotechnical structures. In Europe alone, 11 million tonnes of solid waste is generated per year asa result of the production of almost 100 million tonnes of paper. The objective of this research is todevelop a new geotechnical composite from residues of the deinking paper industry and to present itspractical application, e.g., as a backfill material behind a retaining structure. After different mixtureswere tested in a laboratory, the technology was validated by building a pilot retaining wall structurein a landslide region near a railway line. It was confirmed that a composite with 30% deinking sludgeand 70% deinking sludge ash had a high enough strength but experienced some deformations beforefailure. Special attention was paid to the impact of transport, which, due to the time lag betweenthe mixing and installation of the composite, significantly reduced its strength. The pilot retainingwall structure promotes the use of recycled materials with a sustainable design, while adhering togovernment-mandated measures. Nasl. z nasl. zaslona. Opis vira z dne: 28. 1. 2021. Št. članka 979. Abstract. Bibliografija: str. 16-17.

Pulp and paper mill biomass boilers generate large quantities of ash in Canada with British Columbia (BC) being the highest ash generating province followed closely by Quebec. Generally, the generated ash is landfilled, particularly in BC, with only a small amount being used beneficially. It is anticipated that the difficulty associated with the management of ash will worsen over time as the industry increases its reliance on green fuel. Thus, there is a strong need to identify beneficial uses of pulp and paper boiler ash for the sake of environmental and economic sustainability. The purpose of this report is to provide the first step in this direction, a review of proposed or implemented uses for coal and hog (or wood) ash around the world. Considering both the properties of the ash and local opportunities, this could be the first step toward screening the applications that may apply to individual mills. Several large-scale practices use ash, such as land application (as a nutrient source or as a liming agent), use in the construction industry (as a replacement for cement or as a fill material), and reclamation of mine sites and stabilization of unpaved forest roads. In some cases, relatively small-scale applications have been used which included uses such as a compost component, agent for pH adjustment of liquid streams and slurries, blasting abrasive, and source of quartz for glass manufacturing to name a few. It is important to note that the chemical nature of both fly and bottom ashes can be quite variable due to the type of wood residues combusted as well as combustion equipment used and must be considered in identifying beneficial applications.

Before starting work on the super-article, you should get acquainted with the requirements for the publication of articles in the collection of scientific papers "Building constructures. Theory and Practice ”, founded by the Kyiv National University of Construction and Architecture.The selected collection is intended for researchers, specialists of design organizations and industrial enterprises of the construction industry, doctoral students, graduate students and students of educational institutions in the field of construction.Issues of the collection must be sent to libraries and organizations in accordance with the requirements of the SAC of Ukraine [6] to send abstracts of dissertations, to the libraries of leading specialized research and design organizations, higher education institutions in which -train specialists in the following specialties:192 Construction and Civil Engineering132 Materials Science194 Hydraulic construction, water engineering and water technologies. The article submitted to the editorial board must clearly meet the goals and specializations of the collection, must be written and designed in accordance with the requirements set out in this article.It is recommended to submit a scientific article only in one collection, which meets the requirements of International Ethical Standards, which prohibit the simultaneous publication of the article in different publications., Перед початком роботи надстаттею слід ознайомитись з вимогами щодо публікації статей в збірнику наукових праць «Будівельні конструкції. Теорія і практика», заснованого Київським національним університетом будівництва і архітектури.Обраний збірник призначений для наукових працівників, спеціалістів проектних організацій та виробничих підприємств будівельної галузі, докторантів, аспірантів та студентів навчальних закладів будівельного напрямку.Випуски збірника в обов’язковому порядку розсилаються в бібліотеки та організації згідно вимог ДАК України [6] до розсилки авторефератів дисертацій, в бібліотеки провідних профільних науково-дослідних та проектних організацій, вищих навчальних закладів освіти в яких проходять підготовку фахівці за спеціальностями:192 Будівництво та цивільна інженерія132 Матеріалознавство194 Гідротехнічне будівництво, водна інженерія та водні технології. Стаття, яка подається до редакції має чітко відповідати цілям і спеціалізації збірника, має бути написана і оформлена у відп овідності до вимог, які викладені в цій статті. Подавати наукову статтю рекомендується тільки в один збірник, що відповідає вимогам Міжнародних етичних стандартів, які забороняють одночасну публікацію статті в різних виданях.

According to the U.S. Bureau of Labor Statistics, since the introduction of the Occupational Injury and Illness Classification System 2.01 in 2011, half of all private industry workplace electrical fatalities occurred within the construction industry. Between 2011 and 2019, the Occupational Safety and Health Administration (OSHA) recorded that 378 cases of electrical fatalities occurred during construction projects. OSHA reports show that the greatest number of electrically related fatalities occurred in alterations or rehabilitations and in new projects or addition builds. Many of these construction projects were for single-family, duplex, or commercial building projects. In examining incidents where contacted voltage was recorded, 57% of fatalities occurred when a worker contacted an energy source of over 1,000 volts. Contact with energy sources of 480 volts and 7,200 volts accounted for the greatest number of fatalities. Gaining a better understanding of the jobs being completed and the source of energy contacted can help identify the behaviors and actions that need to be addressed to lower the number of electrical fatalities in the workplace.

This paper reviews the state of field of nanotechnology in concrete technology field. The outstanding chemical any physical property of nanomaterials helps in structural reinforcement and redemption of environmental pollution, and also in producing self cleaning materials. Concrete is one of the most used materials in structural applications, where strength, costing, durability of playing a key role in high attribute of concrete. In this paper we tried to review the application of nanotechnology in concrete production. The paper first presents general information and definitions of nanotechnology. Then, it focuses on the most effective nano- additives that can increase the rheological and hardened properties of concrete.

Steel is used in construction industry due to its hardness and tensile strength. Cold-formed steel is type of steel which is manufactured at lower temperature. Cold-formed steel becomes more popular in twentieth century in civil engineering field as it possesses high strength to weight ratio and post-buckling strength. Research in cold-formed steel has increased considerably in past few years. Researchers have been working to develop direct strength method to replace conventional effective width method which is more tedious and less accurate. In this paper, we have studied various methods adopted for estimation axial load carrying capacity of cold-formed steel channel, angle and Z sections by various researchers.

Construction industry has complexity in its nature because it contains a large number of parties such as clients, contractors, consultants, stakeholders, shareholders, regulators and others. It makes significant contributions to the socio-economic development process of a country. But due to some factors the construction project progress affected in different countries. Therefore this study focused on the identification and ranking of the different factors that affect the construction of project progress in different areas. Keywords: Performance of Construction, Factors affecting Construction Performance, Ranking DOI: 10.7176/CER/12-7-02 Publication date: July 31 st 2020

The present review paper discusses an aspect of influence of pH and weight loss of steel embedded in reinforced cement concrete. Fe415 steel is the widely used steel in construction industry because of its low carbon content and good mechanical properties. To make an analytical study, the Linear Polarization Resistance (LPR) measurement technique has been used for measurement of pH and weight loss in 0.5M NaOH Solution The pH has been varied from 7-10 by a difference of 0.5. An equation which relates the pH and corrosion rates has also been dictated in the present paper. A wide literature review has also been conducted in the present paper. Temperature and the electrode voltage relationship have been shown in the text according to the Nernst equation.

The current “Building a Better New Zealand” initiative began in 2009 with the New Zealand Government and the Building Industry working together to develop “Building the Future”—a document that looked at the challenges and opportunities facing the country’s building and construction industry in coming decades. [...]

This paper provides an overview of the background literature, including a section on the prevailing definitions of undeclared work in construction. Following this introduction, it describes (earlier) research into the construction sector, general results and findings (Section 2). Although empirical evidence at aggregate level is still scarce, proxy evidence can be found in some sector-specific studies. Within the definitions and features section (Section 3), the role of moonlighting, i.e. performing undeclared labour alongside a regular job or self-employment, is a distinctive element of the general literature. The section on measures (Section 4) lists the existing categories, followed by examples of national initiatives recently implemented. Finally, Section 5 questions the current approach and concludes that a tailor-made policy, specifically adapted to the sector, is needed.

Contractor default is one of the major risks that threaten a project’s success in the construction industry. Previous studies have focused mainly on evaluation of the contractor’s financial aspects to predict contractor default. There remains a need for a comprehensive model that has the ability to incorporate the evaluation of all the project aspects, project team, contractual risks, and project management evaluation criteria to predict the possibility of a contractor’s default on a specific construction project. This paper presents a contractor default prediction model (CDPM) from the surety bonding perspective that incorporates these criteria and uses a fuzzy inference system for reasoning. The CDPM provides a more objective, structured, and comprehensive approach for contractor default prediction for surety practitioners, project owners, and for self-assessment by contractors to reduce the risk of contractor default. The multi-attribute utility function was used to develop a group consensus system (GCS) to aggregate the participating experts’ opinions to build the CDPM. The accuracy of the GCS was found to be 91.1%. A novel approach for fuzzy rule base development is applied to develop the rule base for the CDPM. The CDPM was validated using 30 contractor default prediction cases, and the accuracy was found to be 86.5%.

Conventional bricks are the most elementary building materials for houses construction. However, the rapid growth in today's construction industry has obliged the civil engineers in searching for a new building technique that may result in even greater economy, more efficient and durable as an alternative for the conventional brick. Moreover, the high demands for having a speedy and less labour and cost building systems is one of the factor that cause the changes of the masonry conventional systems. These changes have led to improved constructability, performance, and cost as well. Several interlocking bricks has been developed and implemented in building constructions and a number of researches had studied the manufacturing of interlocking brick and its structural behaviour as load bearing and non-load bearing element. This technical paper aims to review the development of interlocking brick and its structural behaviour. In conclusion, the concept of interlocking system has been widely used as a replacement of the conventional system where it has been utilized either as load bearing or non-load bearing masonry system.

PurposeThis paper aims to present findings from research that evaluate the defects/snagging management process at construction project level and review the potential for the operation of a novel, paper‐based, records management mechanism.Design/methodology/approachThe design and use of a hybrid electronic/paper‐based snagging management system are discussed. The design and practicalities of the system are considered as a means towards demonstrating that a link currently exists between modern IT systems and traditional, paper‐based methods of document transfer.FindingsThe paper finds that the snagging aspect of construction projects is often overlooked and under‐estimated. Construction projects require systems that facilitate data input and records management processing, thus removing the reliance upon traditional methods of working. A highly advanced digital pen and paper technology is discussed which has the potential to totally revolutionise the collection of information on paper (for all organisations). The IT system can be adapted for a range of processes/needs which aids not only management but also the individuals on the frontline responsible for collecting site‐based records.Practical implicationsThe system highlighted has the potential to be adopted within every construction‐based organisation and indeed wider industrial sectors due to its unique adaptability and ease with which features can be incorporated. There are a number of business benefits to be accrued from the adoption of digital pen and paper‐based IT systems.Originality/valueExtremely novel technology is discussed. The value to the construction industry and wider industrial sectors is the opportunity to continue working using existing processes, whilst at the same time becoming wholly electronic.

The Editor would like to announce the Best Paper Award winner from the Journal’s four 2013 issues. The Best Paper Award goes to Kathleen M. Leonard and Gillian M. Nicholls for their paper “History and Status of Female Faculty in Civil Engineering” found in volume 139, number 3, published in July 2013. Other nominations were “Innovative Technologies Used to Investigate Segments of the Inca Road” by Edward J. Jaselskis et al. from the same issue, “Work-Life Balance and Organizational Commitment of Women in the U.S. Construction Industry” by E. Kent Malone and Raja R. A. Issa in the April issue, and “Risk-Sharing in Highway Concessions: Contractual Diversity in Portugal” by Carlos Oliveira Cruz and Rui Cunha, also in the April issue. The Editor encourages researchers to dig out issues of the Journal and reread these fine papers. The quality of the Journal depends on the quality of author submissions, and manuscripts of this caliber provide a valuable service to the profession.

Digital federated platforms and data cooperatives for secure, trusted and sovereign data exchange will play a central role in the construction industry of the future. With the help of platforms, cooperatives and their novel value creation, the digital transformation and the degree of organization of the construction value chain can be taken to a new level of collaboration. The goal of this research project was to develop an experimental prototype for a federated innovation data platform along with a suitable exemplary use case. The prototype is to serve the construction industry as a demonstrator for further developments and form the basis for an innovation platform. It exemplifies how an overall concept is concretely implemented along one or more use cases that address high-priority industry pain points. This concept will create a blueprint and a framework for further developments, which will then be further established in the market. The research project illuminates the perspective of various governance innovations to increase industry collaboration, productivity and capital project performance and transparency as well as the overall potential of possible platform business models. However, a comprehensive expert survey revealed that there are considerable obstacles to trust-based data exchange between the key stakeholders in the industry value network. The obstacles to cooperation are predominantly not of a technical nature but rather of a competitive, predominantly trust-related nature. To overcome these obstacles and create a pre-competitive space of trust, the authors therefore propose the governance structure of a data cooperative model, which is discussed in detail in this paper.

Rubberwood, hitherto solely employed as fuel wood has found fairly suitable use in the Nigerian construction industry. This paper investigated the engineering properties of this low cost, alternative, timber material, produced from Rubber trees (Hevea brasiliensis); often employed within two weeks of felling, for the construction of formworks and related wood works. No real attempt has been made to formally grade or coordinate the properties of rubber wood as employed in the Nigerian construction industry. The research was aimed to achieve the determination of the physical and mechanical properties of naturally seasoned rubber wood obtained from the Niger Delta region of Nigeria, and assigned to it a strength/grade class. Specific properties required for grading were determined using suitable standard methods. The structural and mechanical properties of the timber wood were determined using the three point bending test in accordance with standards presented by BS EN 408 and ASTM D193, but with an aspect ratio of 12. Characteristic values for the wood properties (at the tested moisture content “MC”) were determined in accordance with BS EN 384. Adjustments were made to the characteristic values for the mechanical properties, and the density of the timber species at the test MC; to conform with the international reference MC condition of 12% (as specified by BS EN 338), and also 18% MC, to suit standards required for the Nigerian environmental condition (NCP 2). Grading was carried out in accordance with BS EN 338. The characteristic values for the mechanical properties (at 12% and 18% MC) evaluated from test results are as follows; characteristic values for MOR and MOE were 20.191 N/mm2 and 19.283 N/mm2, and 2285.784 N/mm2 and 2195.606 N/mm2 respectively. Mean values for densities (at 12% and 18% MC) were 406.169 Kg/m3 and 431.058 Kg/m3, while the characteristic values for the related densities were 338.474 Kg/m3 and 359.215 Kg/m3. Furthermore, the mean green density and characteristic green density for the rubberwood were 988.148 Kg/m3 and 900.352 Kg/m3 respectively. From the results obtained, rubberwood procured from the Niger Delta region was categorized as a grade D30 and D35 timber material at 18% MC and 12% MC respectively. Rubberwood from the Niger Delta can be conveniently employed as an alternative material to conventional timber, in both the furniture and the construction industry, but with special considerations.

Experienced construction personnel have provided input into construction projects for many years. However, only recently, under the impetus of the Business Roundtable's Construction Industry Cost E...

Introduction. The mixed liquor of nitrogen removal wastewater treatment plants is characterized by a high concentration of nitrates and dissolved oxygen at the inlet to the secondary settling tank. In the sludge layer of secondary sedimentation tanks, conditions of decreased oxygen content and uncontrolled denitrification processes take place. This leads to the floating up and removal of sludge with the effluent and secondary pollution of treated water. The purpose of this article is to study the parameters of activated sludge sedimentation in municipal wastewater treatment plants and their intensification by means of vacuuming. Materials and methods. The studies were carried out under laboratory conditions. Activated sludge vacuuming and sedimentation processes were simulated. Diagrams of the “sludge-water” phase reduction (Kinsh curves) were drawn. Mathematical and graphic processing of the results was carried out. Results. Biological treatment of municipal wastewater (aerotank — secondary settling tank) and methods of its intensification by influencing the activated sludge were considered in this article. Trends of activated sludge (at different concentrations of mixed liquor suspended solids) sedimentation were experimentally obtained for municipal wastewater treatment plants. The process of sludge vacuuming was researched, the process efficiency was determined as a function of the treatment time. Conclusions. Vacuuming allows removing gases from the fluid, which accelerates the process of sludge separation from the treated water and prevents it from floating to the surface. The treated sample is characterized by better sedimentation characteristics, density, coarseness and integrity of flakes. The optimal duration of mixed liquor vacuuming before sedimentation is 0.5 minutes; this accelerates the processes of subsequent sedimentation and reduces the removal of sludge with treated water. The results of laboratory tests can be applied to the design of the mixed liquor vacuuming unit before the secondary sedimentation tanks and its sludge separation.

Nowadays, infrastructure construction is becoming a serious problem globally due to high material consumption. So, there are high demands in the construction industry using the river sand as fine aggregate in concrete production. Pond ash is an industrial waste product from the thermal power plant; such material can be used as a partial replacement of fine aggregate in C-25 grade of concrete. In this research work, each mix's workability was measured before the concrete cast, and the slum was 25 to 50 mm. Concrete cubes of size (150 mm × 150 mm × 150 mm) were prepared with seven different samples containing 0% (control) to 30% pond ash with increment of 5%. From the result obtained, the workability and density of concrete containing pond ash decreased with increase percentage content of pond ash in the mix. The compressive strength of pond ash concrete containing 5% and 10% have shown increment compared to the control concrete by about 0.13%,3.74%,2.46% and 0.04%, 1.14%,0.70% at 7, 14 and 28 days of curing respectively. Finally, in this study, the percentage replacement of fine aggregate concrete up to 10% by pond ash better resulted in compressive strength of concrete is found 34.75 N/mm2 at 28 days. Therefore, the optimum replaced fine aggregate by pond ash is 10%.

The use of concrete in the construction industry is never ending and so are their complementary ill effects. Thus, they should be handled within the stipulated time and in a sustainable manner. The major idea of the present research work is to assess the strength parameters of the concrete specimens made by inducing bacteria along with a suitable cement replacing substance. Therefore, the use of sustainable strategies like inducing bacterial culture into the concrete mix can act as an active support for both nature as well as the economy of construction industries. There are many substitutes which are used for replacing cement. In this paper, control concrete, concrete made by replacing cement with 8% of Micronized Biomass Silica (MBS) and bacteria induced concrete are compared. The bacteria used is Bacillus Sphaericus and is mixed in the concrete specimens at different levels of 10ml, 20ml, 30ml. M60 grade high strength concrete is casted in the form of cubes and cylinders and their compressive strength and split tensile strength at the age of 7and 28 days are compared with that of conventional concrete. From the test results, it was concluded that, specimens with 20ml bacteria and 8% MBS showed optimum results. Hence, this combination of bacteria and MBS would not only increase strength but also help the concrete against moisture and other harmful particles.

As engineers we all take great pride in what we help to construct. We say, ‘‘I worked on that project,’’ or we tell stories about how we solved technical problems that contributed to the success of a constructed work. However, we usually fail to realize that our work in and of itself is an ethical act. Yes, engineers know that the profession has a code of ethics, and without really studying that code we believe we conduct ourselves as ethical engineers. The ‘‘ASCE Code of Ethics’’ is published in the Official Register each year and is also posted on the Society Web site at www.asce.org/inside/codeofethics.cfm. This code was originally adopted on September 2, 1914, and was most recently amended on November 10, 1996. This code of ethics opens with a statement of fundamental principles that ASCE adopted from the Accreditation Board for Engineering and Technology, Inc. ~ABET! ‘‘Code of Ethics of Engineers.’’

A major challenge for construction industry is the durability of structures. A lot of work is being done to strengthen structures. Microbially induced calcium carbonate precipitation (MICCP) or biocementation is an innovative technology, which uses ureolytic bacteria to precipitate CaCO3 to strengthen cementitious materials. In this research, the effect of a bio-solution incorporated with soil as microbial source on the mechanical properties of mortar was studied. Cost reduction in the process was done by using natural ingredients. A considerable increment in compressive strength and a decrement in water absorption of the bio-mortar specimens were observed. Two ureolytic bacteria were identified, viz. Bacillus cereus and Enterobacter cloacae. The effect of these identified ureolytic pure cultures on mortar was also studied.

As the construction industry drives towards sustainability, all construction sectors, including the asphalt pavement, are suggested to explore more environmental approaches in their developments. Despite that the demand for oil is continuously increasing, the production of the worldwide oil is started to diminish due to the depletion of the resources. One of the most promising ways to address this issue is to produce bio-binders or bio-oils from biomass resources that can completely or partially replace the petroleum asphalt binders. This study investigates the effect of bio-oil extracted from local date seeds using Soxhlet method on the performance of asphalt binder used in construction of asphalt roadways. Asphalt mastic was prepared using three volume ratios of 0.0%, 1.5%, and 2.5% of date seed oil (DSO) and one asphalt binder with penetration grade of 60/70 (PG 64–16). Multiple rheological and advanced tests were conducted at different temperatures to assess the different performance parameters and compare it to the Superpave criteria and specifications. The findings of this research study show that the addition of the bio oil to the asphalt binder increases the penetration; however, both softening point and viscosity decreased with the addition of bio oil. On the other hand, the temperature susceptibility and the high-temperature performance grade (PG) of the modified asphalt binder dropped down. Rutting and fatigue performance parameters obtained through the MSCR and LAS tests, respectively, indicated that the addition of the DSO to the asphalt binder increases the nonrevocable creep compliance (Jnr) that leads to a reduction in the rutting performance. However, the traffic level was enhanced to tolerate heavier traffic than the conventional asphalt binder despite the dramatic increase in the strain. The fatigue resistance of the modified asphalt binder was improved explained by the increase in the damage intensity and the number of cycles to failure.

The concrete is widely used in the construction industry. River sand is commonly used construction material. Natural weathering of rocks results in the formation of river sand, over millions of years. Robo Sand (R.S) which is eco-pleasant serves as a partially substitute material for the depleting river sand. The addition of Robo sand can reduce construction cost and also increase the strength of the concrete. Rice husk is by-product from crop growing waste and it is burnt to form Rice Husk Ash (R.H.A) which is used as partially substitute material for cement in concrete. In this study the concrete is prepared with RS as partially substitute material of fine aggregate in different proportions like 0%, 10%, 25%, 50%, 75%, and 100% and R.H.A as partially substitute material for cement in different proportions like 0%, 5%, 10%, 15%, and 20%. For normal and replaced concrete compression strength & split tensile strength is determined.

Red mud (RM) is a toxic waste, rich in coloured pigments, which affects landfills and surrounding environments due to its high alkalinity. But it is suitable for architectural coloured concrete production since it contains a high volume of ferric oxide (Fe2O3), aluminium oxide (Al2O3), and Silicon dioxide (SiO2). Therefore, the application of RM in concrete production not only may benefit the construction industry but also helps mitigating the environmental effects of alumina refineries. In addition, using RM can help to achieve a green coloured concrete with similar properties to current concrete made with white cement. This study intends to appraise the effects of RM in self-compacting architectural concrete (SCAC) production as cement and filler replacement. For that purpose, seven concrete mixes incorporating various ratios of RM as partial cement (2.5%, 5.0%, and 7.5%) and filler (25%, 50%, and 75%) replacement were produced in the laboratory. The results revealed that RM does not significantly affect the performance of concrete, as the variations of the results were mostly lower than 5% in relation to the reference concrete. Moreover, incorporating RM in SCAC can improve the durability to sulphate attack in terms of weight loss, a very important parameter when evaluating the performance of architectural concrete, by about 27%. In addition, using RM can help achieve a green coloured concrete with similar properties to current concrete made with white cement.

Fresh and waste vegetable oils are used as binders in the construction industry instead of cement or clay. In this study, polysaccharides were blended into fresh and waste vegetable oil to function as a binder to produce a tile. Ten different combinations of oil–polysaccharide binders were prepared using ethyl cellulose, glutinous rice flour, potato starch and corn starch. The main raw materials for the tile are fly ash 20%, river sand 70% and oil–polysaccharide 10%. The tile composed of waste vegetable oil with ethyl cellulose showed good mechanical properties, durability and permeability compared with other oil–polysaccharide binders, making it suitable as a decorative floor tile.

It is unclear whether or not internet surveys yield response rates comparable to paper-and-pencil surveys for specific occupational groups, such as construction workers. The objective of this study was to examine the differences in response rates between a paper-and-pencil questionnaire and an internet questionnaire for two construction-related occupations: bricklayers and supervisors. In total 600 participants were randomly assigned to the internet questionnaire survey or to the conventional paper-and-pencil questionnaire survey. Undeliverable postal was excluded from the response rate. A total of 237/590 subjects responded, leading to a response rate of 40% across both arms of the study. Total response rate in the paper-and-pencil questionnaire group (45%, 1311293) was significantly higher (Chi-Square = 4.99, p = 0.025) than in the internet questionnaire arm (36%, 106/297). Among bricklayers, the response rate on the paper-and-pencil questionnaire (44%, 64/147) was significantly higher (Chi-Square 7.36, p = 0.007) than on the internet questionnaire (28%, 42/148). For construction supervisors response rates were not different for both arms of the study, 46% (67/146) on the paper-and-pencil questionnaire and 43% (64/149) on the internet questionnaire. Overall, a paper-and-pencil questionnaire is more effective in terms of response rate than an internet questionnaire in a random sample of two construction professions. Relevance to industry: Questionnaire surveys play an important role in gathering information on interventions aimed at reducing occupational risks and health effects for construction workers. The most effective survey mode should be explored before a large scale survey is carried out. (C) 2011 Elsevier B.V. All rights reserved

Numerous publications have documented successes achieved through partnering. Such notable results have been achieved over a wide variety of applications, including public and private ownership, single-project and multiple-project agreements, and lump-sum and cost-plus contracts. Such accomplishment across a spectrum of application suggests that partnering, if applied properly, can work in almost any environment. Recent research by the Construction Industry Institute highlights this fact that many “shades” of partnering exist, based on the degree of objectives alignment between involved parties. To illustrate this, a partnering continuum has been developed, depicting four general stages—competition, cooperation, collaboration, and coalescence. “Competition” represents the traditional owner/contractor relationship, where each party possesses separate objectives, and minimal effort is expended toward “working together.” This competitive pursuit occurs in the absence of partnering. The other three stages—coop...

This paper research adopted the item response theory and studied the aspects such as the generation of random numbers of the students' ability and the method of identifying and selecting examination questions from the item bank. This paper put forward to the basic principle of paper intelligent-production system, the implementation process, test of fit and so on. Meanwhile the implementation process was simulated in an experiment.

Studies on the construction industries in the developing countries started in the 1960s. The aspects of the subject studied include the key components of the industries, focusing on the problems they were deemed to be facing, and what should be done to develop the industries and enhance their performance. There have been arguments on whether it is appropriate to study the industry in developing countries with concepts and methods developed for industries in different contexts. This short paper contributes to this debate. It is suggested that, after nearly six decades of research, there is now an established subject of knowledge on the “construction industry in developing countries”. It is argued that the context of the industry in developing countries means that more work should be done to modify the existing body of knowledge. Some possible areas where new thinking is evident are outlined.

Automatic Term Recognition (ATR) is concerned with discovering terminology in large volumes of text corpora. Technical terms are vital elements for understanding the techniques used in academic research papers, and in this paper, we use focused technical terms to explore technical trends in the research literature. The major purpose of this work is to understand the relationship between techniques and research topics to better explore technical trends. We define this new text mining issue and apply machine learning algorithms for solving this problem by (1) recognizing focused technical terms from research papers; (2) classifying these terms into predefined technology categories; (3) analyzing the evolution of technical trends. The dataset consists of 656 papers collected from well-known conferences on ACM. The experimental results indicate that our proposed methods can effectively explore interesting evolutionary technical trends in various research topics.

Construction sludge is known as waste material generated from construction industry. Since the construction sludge is usually very soft and at a high water content, it is often necessary to treat it with cement or lime to be recycled as construction materials. However, after the treatment, the increased pH sometimes cannot satisfy environmental regulation. By injecting high-pressure CO2 gas into the specimens, neutralization of alkaline construction sludge was accelerated. This research aims to study the effectiveness of using cement, CO2 gas, and paper sludge (PS) ash for not only lowering the pH level but also strengthening the alkaline construction sludge to be re-used in long-term durability. Alkaline simulated sludge having similar pH levels and state with the actual sludge were produced in the laboratory. The observed results showed that pH was decreased from more than 11.5 to around 8.6 after 7 h curing by the injection of CO2, whereas the addition of PS ash shortened the CO2 curing time. The strength of simulated samples was decreased during CO2 curing but then rapidly increased under air curing conditions. Strength of the samples with PS ash was seen significantly improved compared to that of samples without PS ash. After CO2 curing, under air curing conditions, the pH of treated samples tended to rebound to a certain level less than the original value, but then gradually decrease. It can be seen that the maximum value of pH rebound depends on the pH value obtained at the end of the CO2 curing.

During the last two decades, the European Union regulation has paid more and more attention to the issue of energy efficiency, especially as far as the building sector is concerned. Lately, the adoption of the European Green Deal (EGD) has further fueled interest in the topic. The building industry is expected to step forward towards decarbonization, as well as to mobilize towards a clean and circular economy, so supporting the pursuit of climate neutrality. In this position paper, we aim to discuss three major issues at stake, which are crucial to increase the renovation rate of the building stock and, hence, to the success of the EGD. The first key issue is whether a cost premium has to be expected due to retrofit projects. The second key issue is whether or not the large swing currently experienced in the price premium for building energy efficiency undermines stakeholders’ confidence. The third key issue is whether we need tailored evaluation methodologies for energy-efficient building portfolios.

Now a days, preparation of concrete with conventional materials becomes more costlier due to the growing demand of construction materials. It will lead construction industry, to determine the alternative materials for the conventional without compromising the quality and quantity of construction. After numerous investigations, it is accepted that the preparation of concrete with alternative or industrial waste materials will be possible. In modern days, variety of industrial waste materials like fly ash, silica fumes, paper pulp, GGBFS, brick and quarry dust, etc., are disposed directly to the environment will causes various health, environmental and economic issues. So, it is necessary to effective disposal or treatment method, in order to reduce the above-mentioned social problems. Fly ash (FA) and waste steel slag (SS) are attempted to utilize an effective replacement material for the ingredient concrete. In this study, waste material from steel making industry was used as a partial replacement for fine aggregate (FIA) by varying replacement percentages from 0% to 60% at an interval of 10% in M30 grade high volume fly ash concrete (HVFAC) with different proportions of fly ash (40%, 50% and 60%). The behaviour of HVFAC was assessed by different strength properties at varying curing periods of 3, 7, 14, 28, 56 and 90 days. It is observed 50% replacement of steel slag shows better results when HVFAC was prepared with 40% fly ash, further increment of fly ash reduces the strength concrete irrespective of steel slag replacement percentage.

Compilation of a hundred million word balanced corpus named Balanced Corpus of Contemporary Written Japanese (BCCWJ) is underway at the National Institute for Japanese Language. This corpus is a component of the KOTONOHA super-corpus that covers the full range of modern Japanese from the middle of the 19th century up to the present. The unique characteristics of the BCCWJ consists in that about two third of the samples in the corpus were randomly selected from two statistical populations: one of them consists in the publication data of books, magazines, and newspapers during the years 2001-2005, and the other consists of the set of books registered in more than 13 public libraries of Tokyo metropolis (335,000 different books). The corpus will be publicly available in the first half of 2011.

Background The aetiology of sarcoidosis is not well established. In previous studies, smoking has been negatively associated with sarcoidosis and there are some indications of an association between exposure to silica dust and sarcoidosis. Aims To study the risk of sarcoidosis in relation to silica dust exposure. Methods A longitudinal cohort of construction workers linked with a registry of Swedish inpatient diagnoses. Workers were designated as exposed or unexposed to silica based on job titles in a job–exposure matrix. The relative risk (RR) was analysed with Poisson regression adjusting for age and smoking. Results We identified 371 cases of sarcoidosis among 297 917 male workers. There was an increased risk of sarcoidosis in the medium- to high-exposure group [RR 1.83 (95% confidence interval {CI} 1.14–2.95)]. A stratified analysis according to smoking showed that ever-smoking workers had an increased risk of sarcoidosis if highly exposed to silica dust [RR 2.44 (95% CI 1.37–4.33)] compared to non-exposed ever-smokers. The risk of non-smokers highly exposed to silica was not significantly increased [RR 1.07 (95% CI 0.72–1.58)] compared to non-exposed non-smokers. Conclusion The study indicates an increased risk of developing sarcoidosis in ever-smoking men exposed to silica.

There is a growing need in the construction industry to improve transfer and durability aspects of Portland pozzolana cement. Ureolytic bacteria have recently emerged as potential micro-organisms w...

The sustainability of raw materials used in construction industry consumed large quantities of material has great importance. The use of pore-makers in the brick production is reducing the consumption of clean clay resources as well as lightness of the baked brick body. Many organic or inorganic additives have been used as pore-making in brick production for improving thermal performance. In this study, tea waste (TW) were used at different concentrations in the brick clay mixtures to examine its effects on baked brick properties. In addition to micro-structure investigations, physical, mechanical and thermal properties of bricks produced were investigated. It is concluded that tea waste additive up to 10% in brick body can be used for structural application and isolation while ratios more 10% tea waste additive for only isolation purposes. Tea wastes can be used as a pore-making additive in the brick production. © 2019 Elsevier Ltd

The recovery of cellulose in toilet paper from municipal wastewater is one of the most innovative actions in the circular economy context. In fact, fibres could address possible new uses in the building sector as reinforcing components in binder-based materials. In this paper, rotating belt filters were tested to enhance the recovery of sludge rich in cellulose fibres for possible valorisation in construction applications. Recovered cellulosic material reached value up to 26.6 gm (-3) with maximum solids removal of 74%. Content of cellulose, hemicellulose and lignin was found averagely equal to 87% of the total composition. Predictive equation of cellulosic material was further obtained. The addition of recovered cellulose fibres in mortars bring benefits in terms of lightness, microstructure and moisture buffering value (0.17 g/m(2) %UR). Concerning mechanical properties, flexural strength was improved with the addition of 20% of recovered cellulose fibres. In addition, a simplified economic assessment was reported for two possible pre-mixed blends with 5% and 20% of recovered fibres content. (C) 2019 Elsevier Ltd. All rights reserved.

In modern times issues such as sustainability and carbon footprint have become subjects of significant interest on a global scale. A leading industry in greenhouse emissions is the construction industry, and the industry’s carbon footprint needs to be reduced in order to meet emissions targets. Hemp concrete and rapeseed concrete are two alternative sustainable building materials that can help the construction sector improve and meet those targets. Because of their relatively recent introduction, limited studies are available on the durability of these materials. This paper investigates the effect of long-term accelerated carbonation on hemp and rapeseed concretes manufactured with a natural cement and, in some cases, a polyacrylic acid viscosity modifying agent (VMA). Natural carbonation in an outdoor environment was also studied. It was found that the mixes carbonated quickly under accelerated conditions, however no impact on mass or specimen dimensions were observed. In the case of the VMA mixes, it was found that the compressive strength of the samples was improved compared to the equivalently aged control samples. However, it was found that compressive strength was actually inhibited in the untreated mixes when compared with the control samples.

The reuse of industrial and agricultural wastes is an alternative method to provide low-cost building materials for the construction industry and reduce the environmental pollutions. This study evaluates the feasibility of using a couple of waste materials including palm fiber, palm fiber ash and fiber bundles both individually and in combination with lime to improve strength characteristics of clayey sand. A series of laboratory tests were performed on samples cured for 7, 14, 28 and 56 days to investigate the compaction properties, unconfined compressive strength (UCS) and failure characteristics of the untreated and lime-treated clayey sand. The results demonstrate that the application of all the additives resulted in a noticeable increase in strength, and both treated and untreated specimens exhibited more ductile behavior. It was also revealed that the mixture of lime and fiber performed more impressively compared to that of lime and fiber individually and the UCS of the improved specimens depends on fiber length and curing period. Inclusion of the various proportions of palm fiber, palm fiber ash and lime increased the optimum moisture content (OMC) and decreased the maximum dry density (MDD), while the addition of fiber bundles decreased the value of MDD and OMC. Palm fiber ash was more effective in increasing the UCS of specimens, and fiber bundles had the most significant impact on the variations of compaction properties.

One of the major causes of an increase in the consumption of resources is the progress of the construction industry. Although it leads to new technologies, it heavily contributes to global warming. In this study, the use of sustainable construction materials from waste in brick production with mycelium as a binder is investigated. The ability of mycelium, the root fibers of fungi, obtained from microorganisms is used as stabilizing and binding material on bricks. Forty-eight brick specimens from six design mixes were produced with a size of 200 mm length &times, 90 mm width &times, 60 mm height. The mechanical tests conducted were compressive and flexural strength. The changes in weight were recorded against its age to monitor the progress of mycelium growth inside the brick specimens. From the test, bricks made from sawdust and rice bran with mycelium had an increase of 31.0% to 38.5% in average compressive strength compared to the non-mycelium bricks, respectively. Furthermore, the bricks with mycelium experienced an increase in both flexural strength and midpoint displacement for all types of bricks (rice bran, sawdust, and clay). These mycelium-induced bricks can reduce the use and consumption of traditional construction materials with enhanced mechanical properties.

The present study focuses on the production of an Alternative Fuel (AF) for the cement industry from a Food Residue Biomass (FORBI) product, generated from pre-sorted Household Food Waste (HFW). FORBI is generated by drying and shredding the fermentable fraction of HFW collected door-to-door in the Municipality of Halandri, Greece. The key physicochemical properties such as the net calorific value (NCV), the concentration of heavy metals and chlorine are subsequently determined using well-established international standards (EN and ISO). FORBI is evaluated as a potential AF in terms of technical feasibility and environmental impacts. Based on the characterization, FORBI is classified as a non-dangerous waste according to EWC 20 01 08, European Commission Decision 2014/955. According to EN 15359 it is classified as category 3, 2 and 1 with respect to NCV, Cl and Hg respectively. The study concludes that FORBI is a suitable candidate as a secondary fuel for the cement industry, given its high calorific value along with its low humidity and ash content. Challenges for practical implementation include the relatively high chlorine content, the inclusion of alkalis in the cement produced and the reduction of non-thermal NOx emissions., The data set of the publication can be accessed at: http://doi.org/10.5281/zenodo.3906241

Background Work-related stress in the construction industry increases the prevalence of depression and anxiety among personnel. In low-resource settings such as Nigeria, construction personnel face high demands and severe working conditions but only have a few services to address their mental health needs. With emerging research showing that digital interventions can be used to self-manage mental health across diverse settings, there may be new opportunities to support construction personnel in the construction industry. Objective This study aims to determine the use of digital interventions for mental health management among construction personnel in Nigeria and to explore the factors that facilitate or impede the use of these interventions. Methods This qualitative study explored the perspectives of a convenience sample of 62 construction personnel. The data were subjected to inductive content analysis. Results A total of 6 barrier and 3 motivator themes were identified and categorized into 2 groups. The barrier themes were subcategorized into barriers to adoption and barriers to persistent use, whereas the motivator themes were subcategorized into intrinsic and extrinsic motivators. Lack of awareness and knowledge about the interventions may constitute a barrier to adoption and use. Participants frequently reported concerns regarding their effectiveness and usability. Conclusions This study provides an understanding of the design needs required to facilitate sustained self-management of mental health based on the experiences and expectations of construction personnel with digital interventions.

Sustainability requirements are gaining importance in the construction industry, which needs to take specific measures in the design and construction of concrete structures. The use of recycled aggregates in concrete may be of special interest. Recycling a construction waste will close the life cycle of the original materials (e.g., concrete). Thus, environmental benefits would come from the lower waste generation, and from a lower necessity of raw materials for new structures. The current Spanish code for structural concrete considers the use of recycled aggregates in replacement rates up to 20% by aggregate mass, assimilating their properties with those of concretes without aggregate replacement. Higher substitution percentages would require further testing. In this work, substitution of coarse aggregate for recycled aggregates (with replacement percentages of 25%, 50% and 100%) has been studied, and the concrete&rsquo, s residual properties after exposure to high temperatures (between 350 &deg, C and 850 &deg, C) have been assessed. Compressive strength and capillary water absorption tests were made after heating, and the experiments showed higher residual strength in concretes with the greatest content of recycled aggregates. However, a statistical analysis made with additional data available in the literature seemed to predict otherwise, and the recycled aggregate replacement would have a negative effect on the residual strength.

Background Vibration-induced white finger (VWF) is often assessed using the Stockholm Workshop Scale (SWS) and cold challenge plethysmography. However, long-term longitudinal studies using both methods are scarce. Aims To study the long-term course and prognostic factors of VWF assessed with the SWS and photoplethysmography (PPG), and to examine the effects of lifestyle on PPG score, regardless of VWF status. Methods Forty male construction workers were examined with a test battery and clinical examination in 1994 and 2016/17. Results At baseline, the sample comprised 27 workers with, and 13 without, symptoms of hand-arm vibration syndrome (HAVS). Thirty-five workers reported vibration exposure during follow-up. The mean age of the workers was 60 years (45-78) at follow-up. The paired t-test showed that PPG scores deteriorated from 1994 to 2017 in the 27 workers with HAVS in 1994 (mean difference 2.7 min, 95% confidence interval (CI) 0.2-5.2). However, there was no statistically significant change in SWS scores in these workers over time. Smoking and age were associated with PPG score deterioration. Vibration exposure during follow-up predicted SWS score deterioration: 1000 h of exposure predicted a deterioration stage of 0.09 (95% CI 0.03-0.16). Analysis of all 40 workers showed that 2017 PPG scores were associated with positive serum cotinine and self-reported smoking during follow-up. Conclusions Whereas age and smoking predicted a PPG deterioration, continued vibration exposure predicted worsening of white finger symptoms. The association of PPG score and smoking should be considered in diagnostic and prognostic factor evaluations.