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Dams require high-volume of construction materials and operations over the life cycle. This paper aims to select a proper type of dam structure that can significantly contribute to the sustainability of dam projects.

This research proposes a complementary fuel consumption and carbon dioxide (CO₂) emission assessment method for the alternate dam structure types to assist decision-makers in selecting sustainable choices. Related equations are developed for two common earthen and rock-fill dam structures types in Iran. These equations are then successfully applied to two real dam project cases where the significance of the achieved results are assessed and discussed.

The achieved results of the case studies demonstrate a high deviation of up to 41.3% in CO₂ emissions comparing alternate dam structure scenarios of earthen and rock-fill dam structures. This high deviation represents an important potential for CO₂ emission reduction considering the high volume of the emission in large dam projects.

The life cycle emission assessment of the alternate dam structures, proposed in this research as a novel complementary factor, can be used in the decision-making process of dam projects. The results in this research identify high potential sustainability improvement of dam projects as a result of the proposed method.

Many construction projects are implemented in open-environment job sites and can be significantly affected by various weather conditions. Evaluating the overall impacts of the weather conditions on a project can assist project managers to prepare effectively. Nevertheless, methods measuring the overall adverse impacts of the job sites’ weather condition on the project performance are still missing. This study aims to address this gap.

In this investigation, a survey-based method was proposed to evaluate the overall impacts of the weather conditions on the construction project resources through a new indicator called job site weather index (JWI). The target survey population includes practitioners directly involved in the on-site construction operations.

The JWI suggests the direction of the resource change in new construction projects based on the weather condition. The method was implemented in the road construction projects of Iran and successfully applied to four sample cities. In this experiment, construction workers were identified as the most susceptible resources to the unfavorable weather conditions. Hot temperature above 50°C and cold temperature below −10°C were ranked as the most influential factors for the workers. The results achieved showed high accordance with the trends currently followed in the country.

This research was the first structured method for capturing impacts of weather conditions on the performance of construction resources in open environment construction projects. Implementation of the method in road construction projects of Iran revealed new results that have not been previously identified. The impacts of the company-specific factors on the final productivity rate, however, were not investigated in the research. Investigations accounting impacts of various company-specific factors on the final productivity rate are required.

Safety and productivity are key concerns in the construction projects. While safety looks to the construction workers need to work in a safe environment, productivity affects the project’s profitability and is of a paramount importance from the project owner’s view. The different perspective to the safety and productivity from these two major players in construction projects poses a potential for the conflict between the two. This problem can be fundamentally addressed by methods concurrently improving project safety and productivity. The paper aims to discuss this issue.

To this aim, a discrete event simulation (DES) based framework applicable was proposed for complex and hazardous operations. The utility of the framework was tested using a case study of an eight-story residential building in the north-east part of Tehran, Iran. The excavation and stabilization operation was identified as the most hazardous and critical operation in this case. The framework could improve safety and productivity of this operation by 38 and 4 percent, respectively.

This framework is a complement to the conventional construction project safety and productivity planning methods. Its main application is in complex and hazardous construction operations.

For the first time, a comprehensive framework for concurrently improving safety and productivity of an entire project was proposed in this research. DES was used as the main modeling tool in the framework to provide an ex-ante evaluation foundation applicable to a wide range of construction projects.

Motivated by the high cost of material movements in road construction projects, past studies have used analytical methods to optimize materials logistics plans. A key shortcoming of these methods is their inability to capture the uncertain, dynamic and complex characteristics of the road construction material logistics. Failure to incorporate these characteristics can lead to sub-optimal results. The purpose of this study is to propose the use of discrete event simulation (DES) to address the existing shortfall.

Despite the powerful capabilities of DES models in capturing the operational complexities of construction projects, they have not been previously utilized to optimize the material logistics of road construction projects. The proposed DES-based method in this research captures the operational details of material logistics and uses a heuristic approach to overcome the combinatorial problem of numerous choices. The method was applied to a 63.5 km real-world road construction project case to demonstrate its capabilities.

Six different material types from 28 material sources were used in the case. Approximately 1.5% of the material logistics costs were saved by following the proposed method and choosing appropriate material sources.

This research contributes to the body of knowledge by leveraging the capabilities of DES and presenting a novel method for improving the materials logistics plan of road construction projects. The proposed method provides practitioners with the basis for capturing the key operational details that were overlooked in the past. The proposed method can be adopted in road construction projects to reduce the overall material procurement cost.