Abstract Standardized Work (SW) is an approach originated in the manufacturing industry, which aims to standardize and improve the efficiency of operations cycles, based on the Lean Production Philosophy. SW has the potential to support the implementation of Location-Based Planning and Control (LBPC) as it allows balancing the workload between workers or teams, contributing to the synchronization of processes. The aim of this study is to propose a method for implementing SW as an additional element of LBPC. Design Science Research was the methodological approach adopted in this investigation and an empirical study was carried out in a real estate company, in which the method for implementing SW was conceived and implemented.The following benefits were identified in the study: increase in the degree of process standardization, improvement in process synchronization, increase in the engagement of the work force with process standards, and improvement in terms of time reliability. The main contribution of this research study has been the adaptation of SW in the construction context as an additional element of LBPC. (SW industry cycles Philosophy LocationBased Location Based LBPC (LBPC teams processes company implementedThe implemented standardization standards reliability

Resumo Trabalho Padronizado (TP) é uma abordagem originária da indústria da manufatura que visa a padronizar e melhorar a eficiência dos ciclos de operações com base na Filosofia da Produção Enxuta. O TP tem o potencial de apoiar a implementação do Planejamento e Controle Baseado em Localização (LBPC), pois permite equilibrar a carga de trabalho entre os trabalhadores ou equipes, contribuindo para a sincronização de processos. O objetivo deste estudo foi desenvolver um método para implementação do TP como um elemento adicional do LBPC. Design Science Research foi a abordagem metodológica utilizada, sendo conduzido um estudo empírico em uma empresa atuante no mercado imobiliário, na qual o método para implementação do TP foi concebido e implementado. Os seguintes benefícios foram identificados no estudo: aumento do grau de padronização das operações, melhoria na sincronização entre processos, aumento do engajamento da mão-de-obra com padrões de processo, e melhoria em termos de confiabilidade em relação a prazos. A principal contribuição desta pesquisa para o avanço do conhecimento foi a adaptação da abordagem do TP ao contexto da construção civil como um elemento adicional do LBPC. (TP Enxuta LBPC, LBPC , (LBPC) equipes processos utilizada imobiliário implementado mãodeobra mão obra processo prazos (LBPC

Abstract The “International Group for Lean Construction” aims to adopt a new management philosophy for the Architecture, Engineering, and Construction (AEC) industry. Learning this philosophy can be supported by using active methodologies, especially serious games. This work aimed to analyse the evolution of using serious games as a teaching technique based on problem classes, in the context of the Lean Construction community. A literature review and an analysis of an empirical experience were carried out in an architecture and urbanism undergraduate course. The results demonstrate the evolution of the use of these techniques, as well as their implications for the education and training of AEC professionals. International Architecture Engineering (AEC industry methodologies classes community course techniques professionals

Resumo O “International Group for Lean Construction” busca adaptar à indústria de Arquitetura, Engenharia e Construção (AEC) uma nova filosofia gerencial. O aprendizado dessa filosofia pode ser apoiado pela utilização de metodologias ativas, especialmente dos jogos didáticos (do inglês “serious games”). Este trabalho teve como objetivo analisar a evolução da aplicação de jogos didáticos como técnica de aprendizagem baseada em classes de problemas, no contexto da comunidade da Construção Enxuta.Foi realizada uma revisão sistemática de literatura e a análise de uma experiência empírica, em uma disciplina de graduação de arquitetura e urbanismo. Os resultados demonstram a evolução do uso dessas técnicas, bem como suas implicações para a formação e treinamento de profissionais da AEC. International Construction Arquitetura AEC (AEC gerencial ativas serious games. games . games”) problemas EnxutaFoi Enxuta Foi empírica urbanismo técnicas games”

Abstract The use of wood is often indicated as a decarbonization strategy for the construction sector. However, the CO 2 footprint of native wood, that is, the emissions during wood harvesting, transportation, and processing, depends on the type of forest management practiced. This study quantifies the CO 2 footprint of native rough sawn lumber from forests with three types of harvesting: sustainable management, conventional management, and conventional selective extraction (deforestation). CO 2 emissions were analyzed from harvesting to the end of wood processing based on data from the literature and the Construction Environmental Performance Information System. The CO 2 footprint of rough sawn lumber varies between 25 and 19,860 kCO 2 /m 3 , with the lowest values for wood from sustainable management and the highest for conventional selective extraction. In addition, managed wood stores temporarily in its cell structure ~353kgC/m 3 . Native wood from sustainable harvesting can contribute to decarbonizing buildings, whereas wood from conventional harvesting and deforestation are relevant sources of CO 2 emissions, considering the wood life cycle. sector However transportation practiced deforestation. (deforestation) System 19860 19 860 19,86 m addition 353kgCm kgCm 353kgC kgC buildings cycle (deforestation 1986 1 86 19,8 198 8 19,

Resmo O uso da madeira é frequentemente apontado como uma estratégia de descarbonização para a construção. Entretanto, a pegada de CO2 da madeira nativa, ou seja, que são as emissões decorrentes da sua exploração florestal, transporte e beneficiamento, depende do tipo de manejo florestal. Este estudo quantifica a pegada de CO2 da madeira nativa serrada bruta, proveniente de três tipos de exploração florestal: manejo sustentável, manejo convencional e extração seletiva convencional (desmatamento). Analisaram-se as emissões de CO2 da exploração florestal até o término do beneficiamento da madeira, com dados da literatura e do Sistema de Informação do Desempenho Ambiental da Construção. A pegada de CO2 da madeira serrada bruta varia entre 25 e 19.860 kgCO2/m3, com os menores valores para a madeira de manejo sustentável e os maiores para a madeira de extração seletiva convencional. Além disso, a madeira manejada estoca temporariamente, em sua estrutura celular, ~353 kgC/m3. Madeiras nativas de manejo florestal sustentável podem contribuir com a descarbonização dos edifícios, enquanto as madeiras de manejo convencional e, sobretudo, de desmatamentosão fontes expressivas de CO2 dentro do seu ciclo de vida. construção Entretanto CO seja desmatamento. desmatamento . (desmatamento) Analisaramse Analisaram se Construção 2 19860 19 860 19.86 kgCO2m3 kgCOm kgCO2 m3 kgCO m kgCO2/m3 disso temporariamente celular 353 ~35 kgCm3 kgCm kgC kgC/m3 edifícios sobretudo vida (desmatamento 1986 1 86 19.8 kgCO2m kgCO2/m 35 ~3 kgC/m 198 8 19. 3 ~

Abstract Al and its alloys have a low atomic weight and high strength to density ratio. These properties make them very useful for the construction of parts in automotive industry, such as engine blocks or pistons. Al is prone to corrosion, due to its negative standard E of 1.66 V vs. NHE. In addition, Al corrosion resistance strongly depends on pH. Therefore, it is important to undertake a general study of Al corrosion behavior.

Resumen El sector turístico en la actualidad está marcado por las concepciones de gestión, los espacios y la visión económica de las regiones, territorios y ciudades. Además, se aprecia que, como industria y como campo, debe contribuir al desarrollo social y comunitario sostenible en función de elevar la calidad de vida de los habitantes. El objetivo de la investigación estuvo encaminado en analizar la producción científica sobre turismo sostenible en la base de datos SCOPUS en el período 2022-2024. Para ello se implementó un diseño mixto en dos etapas, con un estudio bibliométrico como principal y una revisión hermenéutica de la literatura adaptada a los intereses cognoscitivos y metas de la investigación. Los resultados de la primera etapa evidenciaron un ligero incremento de la producción del año 2022 al año 2023, siendo las áreas más representativas las ciencias sociales y las ciencias ambientales. En la segunda etapa se examinó la relación entre sostenibilidad y turismo en el marco de los objetivos del desarrollo sostenible, así como las principales tendencias y retos.

Abstract The tourism sector today is marked by management concepts, spaces and the economic vision of regions, territories and cities. Furthermore, it is appreciated that, as an industry and as a field, it must contribute to sustainable social and community development in order to raise the quality of life of the inhabitants. The objective of the research was aimed at analyzing the scientific production on sustainable tourism in the SCOPUS database in the period 2022-2024. To achieve this, a mixed design was implemented in two stages, with a bibliometric study as the main one and a hermeneutical review of the literature adapted to the cognitive interests and goals of the research. The results of the first stage showed a slight increase in production from 2022 to 2023,0 with the most representative areas being social sciences and environmental sciences. In the second stage, the relationship between sustainability and tourism was examined within the framework of the sustainable development objectives, as well as the main trends and challenges.

RESUMEN Introducción: El trabajo en la industria de la construcción se considera precario, deficiente en medidas preventivas y con altas tasas de accidentes y enfermedades laborales; de tal modo que esta actividad es calificada por instituciones e investigadores como un trabajo peligroso. Objetivos: Estudiar el proceso laboral del montaje de estructuras metálicas por medio de una metodología cualitativa, para conocer los riesgos y exigencias existentes en las tareas y estructurar las medidas preventivas conducentes. Métodos: Para realizar esta investigación se utilizaron la Cédula de Información General de la Empresa y llos Diagramas Complejos de Salud en el Trabajo, que forman parte de la metodología llamada Modelo PROVERIFICA para la Verificación, Diagnóstico y Vigilancia de la Salud Laboral en las Empresas. Resultados: Se detectó una amplia gama de riesgos y exigencias en el montaje de estructuras metálicas: polvos de la construcción; radiaciones y humos de la soldadura eléctrica; posiciones incómodas y esfuerzo físico intenso; jornadas de trabajo intensivas y extensivas; y, sobre todo, la posibilidad de sufrir accidentes de trabajo en las maniobras de montaje y al trabajo en alturas. Conclusión: Los trabajadores son la parte fundamental de las empresas, por lo cual se deben efectuar las acciones necesarias para mantener un medio ambiente de trabajo exento de riesgos y exigencias que puedan dañar su salud. Así, es prioritario contar con estadísticas confiables, planes y programas de capacitación de carácter preventivo y estudios periódicos de salud laboral en las empresas, entre otras medidas.

ABSTRACT Introduction: The construction industry is considered dangerous, deficient in preventive measures, and one that has high rates of accidents and occupational illnesses, such that jobs in this industry are classified by institutions and researchers as «dangerous jobs». Objectives: To study, by means of a qualitative methodology, the workplace process of assembling metallic structures, to learn what the existing risks and demands of the tasks in this job are, in order to structure appropriate preventive measures. Methods: To carry out this study, the General Company Information Certificate and Complex Occupational Health Diagrams were used, which are part of the methodology called the PROVERIFICA Model for the Verification, Diagnosis and Surveillance of Occupational Health in Businesses. Results: A wide range of risks and requirements were detected in the assembly of metal structures: construction dust, radiation and fumes from electric welding, uncomfortable positions and intense physical exertion, intensive and long workdays, and above all, the potential for workplace accidents during assembly maneuvers, due to working at height. Conclusion: Workers are the fundamental component of businesses, which is why the necessary actions must be taken to maintain a work environment free of risks and demands that could harm their health. Thus, it is a priority to collect reliable statistics, implement preventive training plans and programs, and conduct periodic occupational health studies in businesses, among other measures.

Resumen: La metodología BIM (Building Information Modeling) se ha establecido como una herramienta esencial en la industria de la construcción. A pesar de esto, en Ecuador el uso de BIM está rezagado, y aunque existen algunas iniciativas en empresas privadas, su uso aún es limitado. El propósito de esta investigación es identificar las consecuencias en el costo y el plazo de proyectos de construcción debido al bajo nivel de uso de la metodología BIM en 30 proyectos de empresas privadas en Ecuador. Para lograr esto, se utilizó la herramienta BUA (BIM Use Assessment) para evaluar el nivel de uso de BIM en cada proyecto durante las fases de planificación y diseño. Posteriormente, se recopilaron datos de costo y cronograma para los proyectos evaluados. Los resultados muestran que las principales consecuencias del bajo nivel de uso de BIM están asociadas con el aumento de costos y plazos. Se concluye que promover el uso de BIM es esencial para mejorar el desempeño de la industria de la construcción en Ecuador.

Abstract: BIM (Building Information Modeling) methodology has established itself as an essential tool in the construction industry. Despite this, in Ecuador the use of BIM is lagging behind, and although there are some initiatives in private companies, its use is still limited. The purpose of this research is to identify the consequences in cost and time in construction projects due to the low level of use of BIM methodology in 30 projects of private companies in Ecuador. In order to achieve this, the BUA (BIM Use Assessment) tool was used to evaluate the level of BIM use in each project during the planning and design phases. Subsequently, cost and schedule data were collected for the evaluated projects. The results show that the main consequences of the low level of BIM usage are associated with the increase in cost and schedule. It is concluded that promoting the use of BIM is essential to improve the performance of the construction industry in Ecuador.

Abstract: Since ancient times, timber has been used as a natural renewable material in construction. Currently in Chile, timber buildings are constructed using platform frame walls. In Ecuador this structural system has not been studied, and it is important to do so in order to promote a greater development in the national construction industry. This paper analyzes the behavior of a timber wall under cyclic and monotonic loads, without vertical load according to ASTM E2126 and ASTM E564 respectively. The wall is made of locally produced eucalyptus timber pieces, covered on both sides with Oriented Strand Board (OSB) panels. The results of the monotonic test showed the maximum capacity of the wall. In the cyclic test, the effective stiffness, effective damping and Story Drift Ratio (SDR) were obtained. It is shown that the specimen has high strength and stiffness, high energy dissipation capacity and is at an immediate occupancy performance level.

Resumen: La madera desde la antigüedad ha sido utilizada como un material natural renovable en la construcción. En la actualidad en Chile, se construyen edificaciones de madera usando muros marco plataforma. En el Ecuador este sistema estructural no ha sido estudiado, siendo importante hacerlo para propiciar un mayor desarrollo en la industria de la construcción nacional. En el presente documento se analiza el comportamiento de un muro de madera ante cargas cíclicas y monotónicas, sin carga vertical de acuerdo con las normativas ASTM E2126 y ASTM E564 respectivamente. El muro está conformado por piezas de madera de eucalipto producidas localmente, recubierto en ambas caras con tableros de virutas orientadas (OSB). Como resultado del ensayo monotónico se obtuvo la capacidad máxima del muro, y del ensayo cíclico la rigidez efectiva, amortiguamiento efectivo y la relación de desplazamiento por piso (SDR). Se demuestra que la probeta tiene una alta resistencia y rigidez, gran capacidad de disipar energía y se encuentra en un nivel de desempeño de ocupación inmediata.

The increased frequency of extreme weather events associated with climate change is a growing concern for road authorities, consultants, contractors and end users. Climate change adaptation is not yet incorporated into South Africa's transport design and planning. Current design methods for asphalt pavements include recently introduced performance-graded (PG) specifications for bitumen. Although the need exists to use future-projected temperature maps in the road industry, the hindrance to this adoption has been extracting the appropriate rising air temperatures from climate model projections. This study focuses on the integration of bias-adjusted historical and projected climate model temperature outputs between 1980 and 2060 to estimate changes in pavement temperatures throughout South Africa to inform a strategy for adaptive material selection. Differences in bitumen selection are observed for the PG 58 and PG 52 maximum temperature grade, and an introduction of PG 70 regions, as derived from climate model data in comparison with the SATS 3208 technical standard. The general trend is a gradual increase in maximum pavement design temperatures, mostly affecting the country's northern and central regions and corresponding road networks. This paper concludes that adjustments are required regarding climate projections for use in bituminous binder selection based on the current specification.

Abstract The main objective of the research was to determine the feasibility of using the Water Footprint (WF) as an environmental indicator in the construction sector, for which a field quantification of this indicator was carried out in four selected single-family housing residential projects in the Greater Area. Metropolitana de Costa Rica, seeing construction as a productive process, and analyzing the results by activity and globally. The direct blueprint in the construction process was calculated through field measurements, carrying out weekly inspections of each project, thus assigning a water consumption per activity according to the progress that was observed. The indirect water footprint (blue and green) for the materials was estimated, based on a series of data on the use of water in production, consulted from the available environmental declarations of each product. Due to the lack of data available in the national context, gray HH could not be estimated. It is concluded that the results obtained could be considered as a first advance in the calculation of HH in the construction industry. To achieve a standard at the national level, it is necessary to encourage local producers or importers to develop environmental product declarations for construction materials and thus generate a robust database on water consumption in their production process. In addition, it is necessary to improve the practices of direct use of water in construction and the quantification of consumption as an indicator of efficiency in potential water savings.

Resumen El objetivo principal de la investigación fue determinar la factibilidad de utilizar la Huella Hídrica (HH) como indicador ambiental en el sector constructivo, para lo cual se realizó una cuantificación en campo de este indicador en cuatro proyectos residenciales de vivienda unifamiliar seleccionados en el Gran Área Metropolitana de Costa Rica, viendo la construcción como un proceso productivo, y analizando los resultados por actividad y de forma global. Se calculó la huella azul directa en el proceso constructivo mediante mediciones en campo, realizando inspecciones semanales a cada proyecto, así se asignó un consumo de agua por actividad según el avance que se observó. Se estimó la huella hídrica indirecta (azul y verde) para los materiales, basándose en una serie de datos de uso de agua en la producción, consultados de las declaraciones ambientales disponibles de cada producto. Debido a la falta de datos disponibles en el contexto nacional, no se pudo estimar la HH gris. Se concluye que los resultados obtenidos podrían ser considerados como un primer avance del cálculo de la HH en la construcción. Para lograr un estándar a nivel nacional se requiere incentivar a los productores locales o importadores a desarrollar declaraciones ambientales de producto de los materiales de construcción y así generar una base de datos robusta sobre el consumo de agua en el proceso productivo de estos. Además, se requiere mejorar las prácticas de uso directo del agua en la construcción y la cuantificación del consumo como indicador de eficiencia de potenciales ahorros de agua.

Resumen El compuesto plástico-madera es un material que combina sustancias distintas, como polímeros y polvo de madera, manteniendo sus identidades incluso después del procesamiento. Estos compuestos se utilizan ampliamente en aplicaciones como muebles, construcción y balcones debido a su durabilidad, resistencia y sostenibilidad. Este artículo bibliométrico tiene como objetivo analizar la producción científica sobre compuestos plástico-madera, identificando tendencias y avances. Utilizando la plataforma Scopus como base de datos, se seleccionaron 835 artículos publicados entre 2010 y 2022. China y Estados Unidos son los países más destacados en la investigación de estos compuestos. Los polímeros termoplásticos como polietileno, polipropileno y cloruro de polivinilo se utilizan ampliamente, al igual que las fibras de madera de especies como pino y eucalipto. Las técnicas de producción más comunes son la extrusión y la moldeo por inyección, mientras que los análisis mecánicos, la microscopía electrónica de barrido, la espectroscopía infrarroja, el análisis termogravimétrico y la calorimetría diferencial de barrido son las técnicas de caracterización más frecuentes. Estos compuestos plástico-madera han sido una opción sostenible y versátil, impulsando la innovación en la industria. Este análisis bibliométrico proporciona información relevante para el desarrollo futuro de materiales y procesos en esta área.

Resumo O compósito plástico-madeira é um material que combina substâncias distintas, como polímeros e pó de madeira, mantendo suas identidades mesmo após o processamento. Esses compósitos são amplamente utilizados em aplicações como móveis, construção civil e varandas devido à sua durabilidade, resistência e sustentabilidade. Este artigo bibliométrico tem como objetivo analisar a produção científica sobre compósitos plástico-madeira, identificando tendências e avanços. Utilizando a plataforma Scopus como base de dados, foram selecionados 835 artigos publicados entre 2010 e 2022. A China e os Estados Unidos são os países mais proeminentes na pesquisa desses compósitos. Polímeros termoplásticos, como polietileno, polipropileno e policloreto de vinila, são amplamente utilizados, assim como fibras de madeira provenientes de espécies como pinus e eucalipto. As técnicas de produção mais comuns são a extrusão e a moldagem por injeção, enquanto as análises mecânicas, microscopia eletrônica de varredura, espectroscopia de infravermelho, análise termogravimétrica e calorimetria diferencial de varredura são as técnicas de caracterização mais frequentes. Esses compósitos plástico-madeira têm sido uma escolha sustentável e versátil, impulsionando a inovação na indústria. Esta análise bibliométrica fornece informações relevantes para o desenvolvimento futuro de materiais e processos nessa área.

Abstract Composite plastic-wood is a material that combines distinct substances, such as polymers and wood powder, maintaining their identities even after processing. These composites are widely used in applications such as furniture, construction, and balconies due to their durability, strength, and sustainability. This bibliometric article aims to analyze scientific production on plastic-wood composites, identifying trends and advancements. Using the Scopus platform as a database, 835 articles published between 2010 and 2022 were selected. China and the United States are the most prominent countries in researching these composites. Thermoplastic polymers like polyethylene, polypropylene, and polyvinyl chloride are widely used, as are wood fibers from species such as pine and eucalyptus. The most common production techniques are extrusion and injection molding, while mechanical analysis, scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry are the most frequent characterization techniques. These plastic-wood composites have been a sustainable and versatile choice, driving innovation in the industry. This bibliometric analysis provides relevant information for the future development of materials and processes in this field.

Abstract: Concrete pavings are widely used in the construction industry as flooring for decorative and structural purposes in the gardens, parks, and roads of America, and Europe. In the present study, the effects of pyrite, corundum, and water-retaining polymer additives on the surface wear resistance of concrete pavings were investigated. Concrete pavings were poured in 2 stages and all of the bottom layers of samples were the same, but upper layers of pavings were produced by adding pyrite in the ratio of 0.10, 0.20, 0.30, 0.40 according to the mass of the aggregate, 5 kg /m2 corundum-based surface hardener to the paving surface area, and a high amount of water-absorbing polymer at a ratio of 0.05 and 0.10 to the water content of the mixture. Vertical abrasion, splitting tensile strength, water absorption, freeze-thaw resistance, pendulum footed friction, and surface hardness measurements with Schmidt test hammer experiments were made to TS 2824 EN 1338 standard. Also, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses were carried out to characterize the produced materials. Results of the study indicate that the use of pyrite, corundum, and water-retaining polymers provided improvements in the surface wear resistance of concrete pavings

Abstract: Numerous research studies have concentrated on advancing a sustainable construction industry through innovative concrete methods and materials. In this context, the present research specifically investigates polymer concrete, utilizing both River sand (R-sand) and Manufacturing sand (M-sand). The polymer content was incorporated into the concrete mix based on the weight of the cement, with varying percentages specifically 2%, 4%, 5%, 6%, and 8%. A slump cone test was conducted to assess the workability of the polymer concrete. Based on experimental studies, the optimal polymer percentage was determined to be 5%. This optimal dosage of polymer content significantly improved the mechanical properties of the polymer concrete. The Compressive Strength (CS), Split Tensile Strength (STS), Flexural Strength (FS), and Modulus of Elasticity (ME) were evaluated at both 7 and 28 days. When using R-sand, the mechanical properties of CS, STS, and FS increased by 13.65%, 12.20%, and 11.42%, respectively. Conversely, employing M-sand led to even greater improvements in strength properties: 19.18% for CS, 12.54% for STS, and 11.67% for FS. Based on the experimental results, the strength properties of polymer concrete M-sand mixes outperformed the R-sand mixes. Linear regression analysis and various codes were employed to predict the strength properties of CS, STS, FS and ME. The regression analysis and various codes successfully forecasted the strength properties of polymer concrete, with the predicted results closely correlated with the experimental results. Based on experimental investigations, the determined mix proportions are recommended for practical applications in various environmental conditions

ABSTRACT The shipyards Center Company as part of the structure of the Military Industry Union, meets of needs to the Revolutionary Armed Forces and the National Economy, with services and products competitive and quality, providing technical naval construction, services modernization, defectation, repair and ships maintenance, boats and all floating media, both in the shipyard and outside its facilities in addition to supporting the national and territorial economy. As part of this corporate purpose, the productive processes. They generate waste that affect the environment of the poof the popular counal of the Reina systematically. Accordingly, decisions have been taken to minimize impact about the environment however, it is not counted, with systemic environment however quality indicators scientifically founded that allow to evaluate the impact and facilitate the decision-making process. As parts of the investigation, a group of environmental quality indicators proposed their validation and its feasibility of use is verified from the experimentation carried out. This makes it possible to verify the importance of the use of the proposed indicators in reducing the impact on the environment of the Queen People's Council and to obtain the procedures for their subsequent generalization.

RESUMEN La Empresa Astilleros Centro, como parte de la estructura de la Unión de Industria Militar, satisface necesidades de las FAR y la economía nacional con servicios y productos competitivos y de calidad, prestando servicios técnicos navales de construcción, modernización, defectación, reparación y mantenimiento de buques, embarcaciones y demás medios flotantes, tanto en el astillero como fuera de sus instalaciones además de apoyar la economía nacional y territorial. Como parte de su objeto social, los procesos productivos generan desechos que impactan en el medio ambiente del Consejo Popular Reina de manera sistemática. En consecuencia, se han tomado decisiones para minimizar el impacto sobre el medio ambiente, sin embargo, no se cuenta con un sistema de indicadores de calidad ambiental fundamentados científicamente, que permitan evaluar el impacto y facilitar el proceso de toma de decisiones al respecto. Como parte de esta investigación se proponen un grupo de indicadores de calidad ambiental, su validación y se comprueba su factibilidad de uso a partir de la experimentación realizada. Ello permite constatar la importancia del uso de los indicadores propuestos en la reducción del impacto sobre el medio ambiente del Consejo Popular Reina y obtener los procedimientos para su posterior generalización.

Abstract: Variation orders became one of the major issues presented in construction projects. The nature of work in the construction industry is complex and difficult. Thus, variation orders are expected to occur in every project due to its nature. The purpose of this study was to investigate the causes of variation orders in construction projects in Egypt according to the perspective of professional parties working for medium and small-sized construction companies. The main method used for data collection was a questionnaire survey with experts working in the Egyptian construction industry, where 62 participants from 18 construction companies were invited to take part in the study, and 51 of them accepted the invitation. The findings showed the top-ranked causes of variation orders according to small and medium-sized construction companies were poor communication, omissions in the design, financial limitations of the owner, additional work requested by the client, and the contractor’s desire to gain more profits. Thus, a proper understanding of the causes of the problem can help establish a suitable criterion for reducing variation orders in construction projects in Egypt. The contribution of this study lies in the fact that only a very limited number of research explored the perspective of medium and small-sized construction companies in Egypt. The study can be useful for other countries with similar working conditions and still suffering from the adverse impact of variation orders.

Resumen: Las órdenes de cambio se han convertido en uno de los principales problemas observados en los proyectos de construcción. La naturaleza del trabajo en la industria de la construcción es compleja y difícil. Por lo tanto, es de esperar que las órdenes de cambio ocurran en cada proyecto debido a su naturaleza. El propósito de este estudio fue investigar las causas de las órdenes de cambio en proyectos de construcción en Egipto considerando la perspectiva de los profesionales que trabajan para empresas constructoras de tamaño medio y pequeño. El principal método utilizado para la recolección de datos fue una encuesta de cuestionario aplicada a expertos que trabajan en la industria de la construcción egipcia. Se invitó a 62 participantes de 18 empresas constructoras a participar en el estudio, de los cuales 51 aceptaron la invitación. Los hallazgos revelaron que las principales causas de las órdenes de cambio para las empresas constructoras de tamaño mediano y pequeño fueron la comunicación deficiente, omisiones en el diseño, limitaciones financieras del propietario, trabajo adicional solicitado por el cliente y el deseo del contratista de obtener más beneficios. La comprensión adecuada de estas causas puede ser útil para establecer un criterio adecuado para reducir las órdenes de cambio en los proyectos de construcción en Egipto. Este estudio contribuye al mejorar el muy limitado número de investigaciones que han explorado la perspectiva de las empresas constructoras de tamaño mediano y pequeño en Egipto. De igual forma, puede ser útil para otros países con condiciones de trabajo similares y que aún sufren el impacto adverso de las órdenes de cambio.