An efficient highway infrastructure network is a determining factor in promoting the socio-economic development of countries and regions. Highway planning activities are highly important because their results ensure that projects are delivered within budget, schedule, and scope. Therefore, academics and professionals have promoted various methodological and technological advances focused on improving highway planning processes, evidenced by many scientific documents that address the topic. Despite progress, few studies have focused on analyzing the state of the knowledge structure and the technological and methodological trends of the highway planning topic. Considering this gap, this study presents trends in highway planning and its knowledge structure based on a bibliometric analysis from January 2015 to September 2021. The research method is based on a bibliometric analysis composed of five main stages: (1) scope definition, (2) selection of bibliometric analysis techniques, (3) data collection, (4) bibliometric analysis execution, and (5) evidence analysis and synthesis. Information from 1703 journal papers was collected and analyzed. The findings show that the main trends of highway planning focus on life cycle analysis, computational tools, smart cities, sustainability issues, construction processes, new equipment and materials, and multi-objective optimization, among others. Thus, the findings of this study allow the reader to identify the methodological and technological trends in highway planning and their knowledge gaps to guide future studies in the field.

Building Information Modeling (BIM) has been widely adopted in the building sector. However, it is still an emerging topic in road infrastructure projects despite its enormous potential to solve ongoing issues. While there have been several recent studies on BIM implementation in road projects, there is a lack of research analyzing the actual BIM Uses in road projects as reported in academic and technical documents. Considering this gap, this paper presents a systematic review of BIM Uses and complementary technologies to BIM in road infrastructure projects. The research method consisted of a systematic review composed of five stages: (1) question formulation, (2) searching of relevant documents, (3) document selection, (4) evidence collection, analysis, and synthesis, and (5) results report. A total of 384 documents were collected, from which 134 documents reporting BIM Uses on roads were analyzed. This study has two main contributions. First, 39 BIM Uses were identified, which are classified into nine categories: road design, traffic analysis, soil aspects, road safety, environmental issues, other engineering analysis, construction planning and analysis, cost analysis, and construction monitoring and control. Second, a set of 26 technologies complementary to BIM adoption in roads were identified, among the most prevalent of which are geographic information systems (GISs) and laser scanning. The results serve as a basis for researchers to learn about the status and propose future developments on BIM adoption in road infrastructure.

Effective construction scheduling is crucial for the success of road projects. However, deficiencies in this scheduling can lead to significant challenges such as delays, cost overruns, and litigation. Therefore, project managers need to understand the causes that contribute to these deficiencies thoroughly. Unfortunately, there has been little research examining these elements in detail. To address this gap, this study examined the causes that affect the scheduling of construction processes for road projects. The research method involved four stages: (1) identification of causes affecting construction scheduling, (2) design and application of a questionnaire, (3) influence analysis, and (4) exploratory quantitative analysis. The study identified 34 causes of deficiencies in the scheduling of road construction processes in six categories: workforce, machinery, material, measurement, environment, and method. Thirty-two experts were consulted to evaluate the frequency and severity of each cause based on a relative influence index. The causes with the greatest impact on deficiencies in road construction scheduling were poor estimation of labor performance, poor estimation of workforce quantity, and deficient coordination with public utilities. The findings allow managers to pinpoint the root causes of road construction planning problems and identify effective solutions.

Forecasting methods, as a control tool, aim to predict final project outcomes and play an important role in assessing the performance of construction projects. In construction, accuracy has been the most important criterion used to assess forecasting performance. However, in addition to accuracy, forecasting systems must provide timely information about project status so corrective action can be taken when required. Therefore, researchers have introduced timeliness as an additional forecasting performance measure. A preliminary study found that some forecasting methods with good timeliness indices do not necessary predict deviations with precision. Furthermore, the cost predictability indices proposed in the literature do not provide sufficient information upon these two desirable features of forecasting methods (timeliness and accuracy). Currently, researchers and practitioners are looking for appropriate methodologies that allow project managers to assess forecasting performance. This study assessed the performance of construction project cost forecasting methods using data envelopment analysis (DEA), based on timeliness and accuracy indices. Preliminary results showed that there is statistical evidence to indicate that the ranking obtained using DEA differs from that obtained using the traditional forecasting performance indices.

Delay is one of the most common and complex issues that adversely affect the performance of construction pro-jects. Although much research exists on project delay, only some studies have systematically summarized and compared the causes of delay by the project type. In addition, few studies have quantitatively combined the variability across studies and related them to the responsibilities of project stakeholders. This study conducted a meta-analysis to provide quantitative and reliable evidence on delay causes combining previous research. This study categorized the top ten causes of delay published in primary research studies, calculated the average aggregate relative important index (RII) of these causes, quantitatively summarized their impact on building and road projects using meta-analysis techniques, and linked them to stakeholder responsibility. Based on an initial 160 top ten-delay causes reported, the study aggregated them into sixteen factors and seven management areas. This research found a different prioritization of delays by project type. Overall, while "site management & technical processes" was the most critical delay factor for building projects, "external issue" was for road projects. The comparison by region shows that "skills, knowledge & experience" was the most critical factor for African studies, but "late delivery and material-equipment issues" was for Asian studies. These factors were related to project stakeholders for defining mitigation actions that led to better project performance. Finally, this study provides a first taxonomy of delays, where the previous causes reported in the literature were clustered into factors and management areas.

The construction industry plays a fundamental role in economic development and job creation, but it faces challenges of labor productivity that have been exacerbated due to the recent COVID-19 pandemic. Labor productivity is a critical component of success, as it influences the duration, costs, and efficiency ofprojects. Understanding the nature of factors affecting labor productivity is essential to finding solutions. This study examined the literature to identify key factors influencing labor productivity, departing from conventional analytical approaches. Through mixed-methods analysis, qualitative approaches of systematic reviews identified influential factors based on 97 documents.Subsequently, they were classified using a combination of statistical analysis and hierarchical clustering methods that encompassed both internal and external factors. The Importance Value Index allowed for the classification of the 30 most critical factors, analyzing three possible ranking scenarios. The study found that the interest in researching the topic remains relevant and has evolved over time. In recent years, greater attention has been paid to labor, management, work environment, and technical aspects. The results indicate that internal project factors, such as scheduling, planning, technical considerations, and resourcemanagement, are more predictable and controllable than external factors. Effective resource management and a comprehensive approach are essential for optimizing construction productivity. Project-level factors, as well as materials, tools, and equipment, play an important role. By synthesizing existing knowledge and identifying and classifying key productivity factors, this study offers valuable insights to construction professionals, policymakers, and researchers seeking to improve labor productivity and optimize project outcomes. La industria de la construcción desempeña un papel fundamental en el desarrollo económico y la generación de empleo, pero enfrenta desafíos de productividad laboral que se han intensificado debido a la reciente pandemia de COVID-19. Laproductividad laboral es un componente crítico de éxito, ya que influye en la duración, los costos y la eficiencia de los proyectos. Comprender la naturaleza de los factores que afectan la productividad laboral es esencial para encontrar soluciones. Este estudio examinó la literatura para identificar factores clave queinfluyen en la productividad laboral, apartándose de los enfoques analíticos convencionales. A través de un análisis de métodos mixtos, los enfoques cualitativos de revisiones sistemáticas identificaron factores influyentes basados en 97 documentos. Posteriormente, se clasificaron mediante una combinación deanálisis estadístico y métodos de agrupación jerárquica que abarcaron tanto factores internos como externos. El Índice de Valor de Importancia permitió la clasificación de los 30 factores más críticos, analizando tres posibles escenarios de clasificación. El estudio encontró que el interés en investigar el tema sigue siendorelevante y ha evolucionado con el tiempo. En los últimos años, se ha prestado mayor atención a la mano de obra, la gestión, el entorno de trabajo y los aspectos técnicos. Los resultados indican que los factores internos del proyecto, como la programación, la planificación, las consideraciones técnicas y la gestión de recursos, son más predecibles y controlables que los factores externos. Unagestión eficaz de los recursos y un enfoque integral son fundamentales para optimizar la productividad de la construcción. Los factores a nivel de proyecto, así como los materiales, herramientas y equipos, desempeñan un papel importante. Al sintetizar el conocimiento existente e identificar y clasificar los factores clave de productividad, este estudio ofrece perspectivas valiosas para profesionales de la construcción, responsables políticos e investigadores que buscan mejorar la productividad laboral y optimizar los resultados de los proyectos.