Ulrich Hermann

Research in Modeling and Simulation for Improving Construction Engineering Operations

Construction simulation, a fast-growing field, is the science of developing and experimenting with computer-based representations of construction systems to understand their underlying behavior. This paper provides a history of construction simulation theory, explores the CYCLONE modeling methodology and its major subsequent developments, examines the development of the Simphony.NET and COSYE modeling environments and their functionality as more generic simulation platforms, and reviews effective strategies for applying simulation in construction. A construction simulation case study is presented that illustrates one successful approach for adopting simulation technology in the industry and outlines the benefits to industry of integrating these technologies. The paper provides an overview of long-term simulation initiatives leading to the next generation of computer modeling systems for construction, where simulation plays an integral role in a futuristic vision of automated project planning and control.

Simulation‐based scheduling of module assembly yards: case study

Purpose – Pipe‐spool module assembly involves a variety of uncertain factors and constraints, which complicate the assembly scheduling process. These factors also pose a challenge for the scheduler who struggles to produce a schedule that optimizes both the use of available resources (e.g. space) and meets the projects delivery deadlines. In the relatively quick production cycle of module assembly, the scheduling process plays an operative role. Thus, automation of the process would enhance productivity of the schedule updating process. This paper seeks to address this issue.Design/methodology/approach – A simulation‐based approach is presented for scheduling pipe‐spool module assembly. This approach incorporates physical and logical constraints. General purpose simulation (GPS) is used to model these logical and heuristic constraints.Findings – The application of the proposed model to an actual case study demonstrates the significant improvement in the assembly schedule when compared to traditional CPM‐...

Interactive and Dynamic Integrated Module for Mobile Cranes Supporting System Design

Analyzing and designing a crane supporting system can be time-consuming process. In particular, the dynamic nature of mobile crane operations entails a variety of reaction values for truck and crawler cranes. The platform of a mobile crane can either be set on outriggers—denoted as a truck crane, or on a crawler tracks—denoted as a crawler crane. Designing of a mobile crane supporting system depends on the lifting configuration, type of crane and the type of materials to be used under the crane outriggers or crawler tracks. This paper presents an automated system which is designed to assist practitioners in calculating the mobile crane’s support reactions and in designing the supporting system. This system is developed such that it can generate a 2D reaction influence chart which shows the reactions for each outrigger at varying horizontal swing angles and vertical boom angles to the ground. Most of the geometric configurations needed to perform the support design are not ordinarily given in crane manufac...

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.

An Integrated System to Select, Position, and Simulate Mobile Cranes for Complex Industrial Projects

Determining feasible mobile crane configurations and positions on a complex industrial construction projects that are free of spatial conflicts and the subsequent scheduling of the lifts is important to the productivity and safety of a project. This paper focuses on the integration of a crane dimensional and capacity database with a projects lifted object information to select and position the cranes and then utilize expert knowledge to simulate the heavy lift plan. The system uses dimensional and coordinate data instead of CAD software for computation of crane position areas amongst known obstructions and boundary limits. The crane position area is specific to a crane model and identifies where the center of rotation of the crane can be placed without having any part of the crane body contact the known obstructions and boundary limits. This analysis is performed for multiple cranes and lifted object scenarios to develop a list of possible options. Schedule date constraints and logic are used to simulate and optimize the schedule and crane selection. This provides the practitioner with an effective planning tool to select, position and schedule cranes.

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...

Spatial Trajectory Analysis for Cranes Operations on Construction Sites

Managing the behavior and trajectory of an object lifted by a crane is critical to a successful lift. This paper presents advancements in the development of mathematical algorithms for lifted object trajectory paths and analyses. The proposed methodology is divided into smaller manageable phases to control the process and at the same time to create independent modules. Each step of the lifted object movement was geometrically tracked, starting at the lifted object pick-point, through an optimum path development and completing at the object final position (set-point). Parameters such as the minimum distance between the lifted object and passing obstructions and minimum allowable clearance between the lifted object and the crane boom are some of the many predefined rules which were taken into account. The lifted objects spatial trajectory analysis and optimization is a part of the complex assignment relating to the crane selection process. A numerical example is presented to demonstrate the effectiveness of the proposed methodology and illustrate its essential value.

Application of Robotic Obstacle Avoidance in Crane Lift Path Planning

Crane lift path planning aims to find a collision-free trajectory for the lifted object among on-site obstacles from its pick location to the final location. However, the current manual planning process is time-consuming, prone to errors, and requires the practitioners to have exceptional visual abilities, since the construction site is congested and dynamically changing. Therefore, the need for developing a decision support system, to automate the crane path planning process, is quite eminent. This paper presents a methodology based on robotic motion planning to numerically solve the crane path planning problem. The proposed methodology conducts 2D path planning for a crane lift operation and accounts for the rotation of the lifted object during its movements. The proposed methodology has been implemented into a computer module, which provides a user-friendly interface to aid the practitioners to perform a collision-free path planning, and check the feasibility of the path at different stages of the project. Two examples are described in order to demonstrate the effectiveness of the proposed methodology and illustrate the essential features of the developed module. This research project is supported by PCL Industrial Constructors Inc.

Innovative System for Off-the-Ground Rotation of Long Objects Using Mobile Cranes

Managing heavy-pressure vessel lifts on construction sites requires planning, arranging adequate crane support, and preparing collision-free rotation (from a horizontal position to a vertical position) of the vessel. Generally, selecting mobile cranes and developing engineered lift studies for vessels are done using two cranes and analyzing the lift for each crane individually on the basis of the selected cranes’ lift-capacity specifications provided by crane manufactures. This practice is relatively costly and time-consuming. Optimizing the mobile cranes’ use and location is also difficult. To assist in the field operation of mobile cranes and to provide engineers with a planning tool, this paper presents a methodology to carry out such a lift utilizing only one crane. Using the developed methodology and mechanism, heavy vessels can be rotated off the ground (in the air) with one crane. The proposed mechanism is supported with a mathematical model that has been developed into a computer system and has been integrated with a previously developed crane selection and ground pressure calculation system and crane database. The developed system provides users with a lift study analysis for a given configuration as well as simulation results with interactive graphics to assist in the selection of an optimum configuration. This research is important as projects involving heavy lifts need to reduce the cost and time associated with construction operations.