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It is a well-accepted note that to enhance safety performance in a project by preventing hazards, recognizing the safety leading indicators is of paramount importance.

In this research, the relationship between safety leading indicators is determined, and their impacts on the project are assessed and visualized throughout the time of the project in a proactive manner. Construction and safety experts are first interviewed to determine the most important safety leading indicators of the construction industry, and then the relationships that may exist between them are identified. Furthermore, a system dynamics model is generated using the interviews and integrated with an add-on developed on the building information modeling (BIM) platform. Finally, the impacts of the safety leading indicators on the project are calculated based on their time of occurrence, impact time and effective radius.

The add-on generates a heat-map that visualizes the impacts of the safety leading indicators on the project through time. Moreover, to assess the effectiveness of the developed tool, a case study is conducted on a station located on a water transfer line. In order to validate the results of the tool, a survey is also conducted from the project's staff and experts in the field. Previous studies have so far focused on active safety leading indicators that may result in a particular hazard, and the importance of the effects that safety leading indicators have on another is not considered. This study considers their effects on each other in a real-time manner.

Using this tool project's stakeholders and staff can identify the hazards proactively; hence, they can make the required decisions in advance to reduce the impact of associated events. Moreover, two other potentially contributions of the presented work can be enumerated as: firstly, the findings provide a knowledge framework of active safety leading indicators and their interactions for construction safety researchers who can go on to further study safety management. Secondly, the proposed framework contributes to encouragement of time-based location-based preventive strategies on construction sites.

The purpose of this paper is to determine the failure progression resistance of the steel moment-resisting frames subjected to various beam-removal scenarios after application of the design earthquake pertinent to the structure by investigating a generic eight-story building.

The structure is first pushed to arrive at a target roof displacement corresponding to life safety level of performance. To simulate the post-earthquake beam-removal scenario, one of the beam elements is suddenly removed from the structure at a number of different positions. The structural response is then evaluated by using nonlinear static and dynamic analyses.

The results show that while no failure is observed in all of the scenarios, the vulnerability of the upper stories is much greater than that of the lower stories. In the next step, the structural resistance to such scenarios is determined. The results confirm that for the case study structure, at most, the resistance to failure progression in upper stories is 58 percent more than that of lower stories.

Failure and fracture of beam-to-column connections resulting in removal of beam elements may lead to a chain of subsequent failures in other structural members and eventually lead to progressive collapse in some cases. Deficiency in design or construction process of structures when combined by application of seismic loads may lead to such an event.

Post-earthquake fire (PEF) can lead to a rapid collapse of structures partially damaged by earthquake. As there is almost no established PEF provisions by codes and standards, PEF investigations are therefore needed for those buildings. The paper aims to discuss these issues.

A non-linear PEF analysis comprises three steps, which are the application of gravity loads, earthquake loads and then fire loads. As a fire generally initiates on one floor and then spreads to other floors, applying a sequential fire is more realistic than applying a concurrent fire on several floors. Hence, in this study, the fire is applied sequentially to the floors with a time delay.

The results indicate a substantial reduction in the resistance of the damaged frame when subjected to PEF. In addition, the results of applying the PEF sequentially is more realistic than the concurrent fire.

It was better to perform an experimental test to have a better understanding of the issue.

PEF can potentially result in a catastrophe in areas located in seismic regions. Thus, investigating the effect of PEF on previously damaged structures is of importance.

Post-earthquake fire (PEF) is considered as one of the most problematic potentially possible disasters in urban areas, as it may result in a conflagration. Most standards and criteria, however, ignore the possibility of fire after earthquake and therefore, majority of conventional buildings are not designed to resist thermal loading after an earthquake. Thus, there is high likelihood of rapid collapse for those buildings damaged partially after an earthquake, which are subjected immediately to a following fire. An investigation based on sequential analysis inspired by FEMA356 is performed in this paper on two RC frames; three and five stories at the Life-Safety performance level and designed to the ACI 318-08 code after they are subjected to a spectral PGA of 0.35g. This is followed by a five-hour fire analysis of the weakened structures, from which the time it takes for the damaged structures to collapse is calculated. As a point of reference, the fire resistance is also determined for undamaged structures and before the occurrence of earthquake. The results show that the structures previously damaged by the earthquake and exposed to PEF are more vulnerable than those that are not damaged. A CPEF greater than 1 is then introduced as a function of fire extinguishing or evacuating time that can be multiplied by the base shear at the time of design in order to increase members sizes and thus improve the PEF resistance. Whilst the investigation is for a certain class of structures (ordinary buildings, intermediate reinforced concrete structure, three and five stories), the results confirm the need for the incorporation of post earthquake fire in the process of analysis and design, and provides some quantitative measures on the level of associated effects.