PROCESS-BASED SIMULATION LIBRARY FOR CONSTRUCTION PROJECT PLANNING

ABSTRACT This paper presents a process-based discrete-event simulation library for construction project planning. Business process models are used to build an accumulative knowledge base for standard construction processes in form of a ready to use process templates. The library aims to reduce the time and efforts needed to create simulation models for a construction project throughout its lifecycle by integrating process models with simulation models and provide a set of reusable simulation components. The paper presents the concepts and describes the architecture of the system with briefly review of its features

A Review of Building Information Modeling and Simulation as Virtual Representations Under the Digital Twin Concept

Building Information Modeling (BIM) is a highly promising technique for achieving digitalization in the construction industry, widely used in modern construction projects for digitally representing facilities. Nevertheless, retains limitations in terms of representing construction operations. The digital twin concept may potentially overcome these limitations and initiate advanced digital transformation in the construction industry as it has revolutionized the product lifecycle management in the manufacturing industry. This research provides a critical review of applying digital twin in the construction industry. Altogether, 140 papers from related journals and databases were reviewed. The digital aspect of twinning consists of BIM and simulation modeling. These two techniques have been used to create virtual or digital representations of actual buildings and real-world construction processes. However, integrating and applying BIM and simulation modeling according to the digital twin concept remains to be fully studied. Comprehensive evaluations of BIM, simulation modeling, and digital twin will provide a well-defined framework for this research, to identify direction and potential for digital twin in the construction industry, thereby progressing to the next level of digitalization and improvement in construction management practice

Modelling and simulation of factors influencing on-site construction of concrete frameworks : Studying the effects of resource allocation, weather conditions, and climate-improved concrete

Concrete is the most common material used to build the structural framework in multistory buildings. However, the construction works carried out on the building site are affected by many different factors that may reduce productivity. Delayed material deliveries, poor planning and coordination of work tasks and production resources, as well as unfavorable weather are examples that reduce productivity. Reduced productivity results in extended construction duration and increased costs for the concrete framework, which ultimately can affect the entire construction project. It is therefore important to increase knowledge about how different factors affect productivity to avoid construction delays and increased costs.Studying how different factors affect productivity is complex as a production system may consist of a large number of factors that can affect the outcome. One method that makes it possible to describe and study complex production systems is discrete event simulation (DES).The aim of this research is to increase knowledge about how DES can be used to systematically analyze the impact of factors that affect productivity during construction of a concrete framework structure. Three factors that are considered to be particularly important for concrete production methods are included in this research study, namely: 1) utilization of labor and crane resources, 2) impact of varying weather conditions, 3) use of climate-improved concrete.Considering utilization of labor and crane resources (factor 1), this study shows that DES is a suitable method for studying in detail how the utilization of these resources affects construction time and cost of the framework. The study highlights the importance of describing the production process in detail to enable identification of workflow bottlenecks caused by resource allocation conflicts. To support identification and analysis of bottlenecks and corrective measures, it is suggested that the traditional performance measures time and cost are supplemented with two additional indicators, namely waiting time and utilization rate.Regarding the impact of weather (factor 2), this study contributes with new knowledge about how this can be described and studied by using DES. The basis for this is a definition of a weather function that describes the relationship between weather and labor productivity. In addition, another function is described that considers the effect of actual weather conditions on the development of concrete strength, which is also important for the productivity of the concrete production cycles. In this way, the impact of weather when using climate-improved concrete can also be studied (factor 3). By implementing these functions in a discrete-event simulation model together with weather statistics, the impact of different weather conditions was simulated. A separate calculation tool was also developed to supplement simulated construction duration of the framework with cost and climate impact. The results from the simulations show that the weather has a significant impact on construction duration of the concrete framework. For example, the construction duration increases in the range 8-42% compared with a reference scenario that is unaffected by weather. The extended duration depends on the season for construction and where the project is located, but also on the extent to which climate-improved concrete is used. The results also show that climate-improved concrete has a significant potential to reduce CO2-emissions of a concrete framework during the construction phase. But to realize the potential of climate-improved concrete also in periods with colder weather, selection of appropriate curing methods becomes imperative. At a more detailed level, a questionnaire survey was also conducted in which contractors estimated the impact of weather on productivity for typical concrete work. These results confirm the importance of the impact of the weather also at a work task level.This study describes how DES can be used to systematically study and analyze how the productivity of construction-related production systems is affected by various factors. The study also provides new insights into how resource utilization, weather, and climate-improved concrete affect the construction of concrete frames. In overall, this can lead to a better basis for planning and selection of production methods to enable increased productivity

Harnessing the power of simulation in the project management / decision support aspects of the construction industry

This paper reviews the history of construction simulation systems in light of their graphical representation of com-plex scenarios. The simulation of construction operations has been a growing field of research over the last several decades. Since the introduction of the first simulation sys-tem, which was based on the activity cycle diagram para-digm of modeling, numerous additional tools have been introduced, each building on and expanding the modeling and analytical capabilities of previous approaches. How-ever, despite such rich body of knowledge, which by now is expanding into areas such as visualization, animation, and virtual reality applications for construction project management, the beneficial application of simulation in practice has been marginal. This paper describes both his-torical and practical reasons for this situation and presents an ontology-based approach that can harness existing in-formation in construction project management, especially the scheduling function, and has the potential to signifi-cantly improve its operational planning and optimization.

HARNESSING THE POWER OF SIMULATION IN THE PROJECT MANAGEMENT / DECISION SUPPORT ASPECTS OF THE CONSTRUCTION INDUSTRY

This paper reviews the history of construction simulation systems in light of their graphical representation of complex scenarios. The simulation of construction operations has been a growing field of research over the last several decades. Since the introduction of the first simulation system, which was based on the activity cycle diagram paradigm of modeling, numerous additional tools have been introduced, each building on and expanding the modeling and analytical capabilities of previous approaches. However, despite such rich body of knowledge, which by now is expanding into areas such as visualization, animation, and virtual reality applications for construction project management, the beneficial application of simulation in practice has been marginal. This paper describes both historical and practical reasons for this situation and presents an ontology-based approach that can harness existing information in construction project management, especially the scheduling function, and has the potential to significantly improve its operational planning and optimization.