Hosein Taghaddos

Automated Method for Checking Crane Paths for Heavy Lifts in Industrial Projects

AbstractAt present, industrial projects are constructed primarily using a prefabricated approach. The modules are produced in an off-site facility and transported on transport trailers to the construction site where they are lifted by mobile cranes. One of the keys to the success of modular industrial projects is efficient crane planning, which includes path checking to find whether or not a crane has a feasible path through which to lift a module over obstructions in a congested plant. However, due to the large number of lifts, the manual path-checking practice is quite tedious and prone to error. In light of this problem, this paper proposes a methodology for automatically checking the lift paths for industrial projects. The proposed methodology simplifies and represents the three-dimensional site layout using project elevations. For each elevation, the crane feasible operation range (CFOR) is calculated based on the crane’s capacity and clearances, as well as site constraints. The pick area (PA) is cal...

Simulation-Based Multiple Heavy Lift Planning in Industrial Construction

Heavy lifting in industrial construction involves the installation of prefabricated modules and equipment weighing up to 1000 tons. Placing a prefabricated module requires a specific crane with a minimum capacity and specific configurations and riggings. Site construction process should follow a certain sequence. If the required cranes are not available or the predecessor modules or structures are not built yet, the module has to be stored in a storage area. Prior to lifting a module, several supporting tasks must take place including adjusting the location, configuration, and rigging of the crane and preparing the ground beneath the crane. Therefore, planning multiple heavy lifts is a complex process. However, it has a significant impact on the cost, schedule and safety of the project. This study employs a simulation-based approach to produce a heavy lifting planning system for mobile cranes. This system assists the project manager and lift engineer in decisions regarding the selection of mobile cranes and their locations and configurations for different lifts. It also produces a schedule that reduces the total cost and enhances the schedule of the project. This system is under implementation on an industrial plant in the province of Alberta, Canada.

INTEGRATED SIMULATION-BASED SCHEDULING FOR MODULE ASSEMBLY YARD

Producing a schedule for industrial construction that optimizes resource utilization and meets the delivery dates of competing projects is a complicated task. The scheduler must consider several constraints and uncertainties including limited space, crew skill, and shipment processes in the module yard. This paper presents an integrated simulation-based scheduling framework that pulls the data from a database interface, runs the simulation model, and provides different graphical reports to the user. Although this model has been implemented successfully in the industry, some challenges are not yet solved. A distributed simulation system using High Level Architecture (HLA) is proposed to break down the simulation into a number of components to enhance the performance of the system. This system also helps to reuse these components in future projects and to facilitate the expansion of the model, enabling more complicated process simulations.

Algorithm for Mobile Crane Walking Path Planning in Congested Industrial Plants

AbstractOn-site construction of industrial projects relies heavily on large mobile cranes for the lifting of prefabricated modules, which over the years have become heavier and more voluminous. Industrial construction sites are frequently congested, a condition that reduces the area where cranes can freely maneuver. As a result, in some cases mobile cranes may not have sufficient clearance to perform the lifts and thus need to pick and walk with loads to a point from which the modules can ultimately be set in their resting positions. Since this type of crane operation presents higher risks of failure or accident in comparison to the traditional scenario, in which the location of the crane does not change for the duration of the lifting, a detailed analysis of these operations is paramount to ensure safety and efficiency. Paradoxically, many practitioners still rely on their best judgment for crane walking planning, which in the case of highly congested and complex construction sites is likely to lead to i...

Distributed agent-based simulation of construction projects with HLA

Simulation techniques can provide a resource-driven schedule and answer many hypothetical scenarios before project execution to improve on conventional project management software applications for large-scale construction projects. However, the current process of simulation and optimization of resource utilization is a time consuming process especially for large-scale projects. This study employs High Level Architecture (HLA) to develop distributed agent based simulation models. These models are composed of several individual modeling components (federates) that can cooperate with each other for the simulation model (interoperability). These federates are developed in a generic way for reuse on future construction projects. A number of agent-based federates are considered for managing various aspects of the project and to enhance the performance of the simulation model. This framework is illustrated using two case studies, module assembly yard and tower crane, that investigate the feasibility of the proposed approach.

Developing complex distributed simulation for industrial plant construction using high level architecture

Large, complex construction projects, such as industrial plant construction, are not well suited to discrete-event process interaction simulation. The authors present a distributed simulation of industrial plant construction using separate modules inter-linked via the High Level Architecture (HLA). This enables the capture of all features, resources, and processes required to design, build, and maintain a facility, and an HLA-based approach simplifies collaborative development and improves reusability of components. The proposed methodology for simulating industrial construction is validated using COSYE, a Construction Synthetic Environment developed at the University of Alberta.

Simulation-Based Scheduling of Modular Construction Using Multi-agent Resource Allocation

Modular construction is common practice for building industrial plants in the Alberta oil sands region, Canada because of the savings in cost and schedule, and improving safety and quality. Each module represents a unique construction project. Thus, modular construction is considered as multi-project construction. Scheduling and effective allocation of resources (e.g., space, skilled crew, construction equipment) in such large-scale construction projects is a challenging process. The production schedule is expected to satisfy numerous uncertain factors and constraints posed by the site layout, resource limitations, the construction process, and various supply chains (e.g., spool fabrication shop). Traditional network-based scheduling approaches are ineffective in scheduling the multi-project environment of modular construction and optimum allocation of resources. This paper presents a hybrid approach based on discrete event simulation modeling and Multi-Agent Resource Allocation (MARA) for scheduling modular construction. Modules represent agents who bid for resources (e.g., space in the yard) to maximize their individual welfare. An auctioneer is also designed who allocates the available resources to the bidding agents by maximizing the overall welfare of the society of agents. The auctioneer can employ various combinatorial optimization algorithms (greedy and ascending-auction algorithms in this study) to allocate the resources to the agents. Auctions are held regularly until the end of the simulation model to allocate the resources among agents. This paper also presents the successful implementation of this approach in an actual case study of a module assembly yard.

BIM obstacles in industrial projects : a contractor perspective

Using BIM technology is well established in construction projects, especially in industrial projects where a maze of pipes and modules have to be installed in congested work areas under tight time schedule . BIM offers potential benefits (e.g. visualization, collaboration, alignment ...etc.) that can be key for complex project success; however, these benefits have not been fully implemented in industrial projects. The authors worked last two years closely with a construction company -which specialized in oil and gas projectstrying to discover ways to maximize utilization of knowledge embedded in BIM models. Though the partner company has used BIM for long time, we noticed many obstacles that hinder reaping the full benefits of BIM for construction planning and control. These obstacles are related to the ability to extend a model by adding new attributes and to link the model to data from external sources (e.g. cost or schedule control information systems). This paper discusses these obstacles, illustrates implemented short-term solutions to work around and mitigate these obstacles, and finally concludes by proposing using semantic web as a long-term solution to overcome these obstacles and clear the path for gaining all potential benefits during industrial projects construction.

A simulation-based method for effective workface planning of industrial construction projects

Abstract The generation of well-defined and moderately sized field installation work packages for the construction workforce, referred to as workface planning, has been recently employed to plan large-scale industrial construction projects under tight schedules. However, traditional CPM-based scheduling of several thousand work packages (e.g. 5000 activities multiply by 10 work packages per activity on average) is a tedious, error prone process. Defining proper logics and controlling congestion among work packages crossing several work areas, and also effective resource allocation over time are other major challenges in workface planning. This paper presents a novel simulation-based framework to implement workface planning for large-scale industrial construction projects. This framework proposes a time-stepped discrete event simulation-based modelling for dynamic resource allocation based on congestion and other constraints on the job site. The proposed method is demonstrated and tested against traditional CPM-based solutions based on an actual case study.

A conceptual accident causation model based on the incident root causes

The measurement and control of incident root causes allows for proactive actions to mitigate risk in advance. In practice, however, it is difficult to identify and collect data that represent the root causes due to the complexity of incident occurrence processes. Despite previous studies on incident causation modelling, the identification of root causes in practice still relies on the investigator’s subjective opinion. This research presents a conceptual model that explains the causal relationships between the root causes and the site unsafe level, and eventually assesses incident investigation processes. A case study was conducted to evaluate the 13 root causes in a company’s investigation practice. The causal relationship between the root causes was observed based on the company safety database, interviews, and literature review. Then, the detailed model, which explains the incident occurrence process, was explored. Additionally, a hypothetical simulation model that allows for evaluation of the influence of each root cause on the safety level was built and tested to discuss the potential use of the conceptual model. Based on the company database, this paper also suggests and discusses the types of data to measure the root causes in practice. The model demonstrates that not only do safety personal and safety strategies affect the site unsafe level, but other factors also do, such as procurement, engineering, human resources, etc. As a result, the proposed model can be used to help identify the root cause in incident investigation practice and to develop strategies to improve safety performance.