Janaka Y. Ruwanpura

Special purpose simulation template for utility tunnel construction

Utility construction projects have great opportunities for simulation applications in construction. The paper describes the special purpose tunneling simulation template developed based on the tunneling operations performed at the City of Edmonton Public Works Department for shielded tunnel boring machines. The tunneling operations are described, then the tunnel template and its components are illustrated. The results generated from the template using the historical data to test the template and to analyze the potential construction processes are presented. Future embellishments to the tunneling template are briefly described.

Construction Productivity Improvement: A Study of Human, Management and External Issues

Advancements in construction are concentrated largely on producing innovative practices to perform construction projects in an efficient and timely manner. Understanding the relationship between performance on the job site and level of productivity is important to develop best and innovative practices to improve construction productivity. This paper explains the ongoing research project within Alberta construction industry to identify the most critical aspects in terms of human, external and management issues that affect construction productivity. The pilot study interviewed very experienced personnel from the construction sector not only to prioritize the factors but also to identify the measurement criteria to improve future construction projects. The second phase of the research and the deliverables are also outlined in the paper.

Why Cost and Schedule Overruns on Mega Oil Sands Projects

Developing and constructing oil sand megaprojects are huge technological, engineering, and construction achievements for Alberta and Canada. Thousands of engineering and project management professionals and workers are contributing to the current effort with great pride and sense of satisfaction. But recent large capital oil sands construction projects have all experienced significant cost and schedule overruns. There are a number of reasons for these overruns. This paper provides a definition of a “megaproject,” illustrates the challenges in delivering oil sands megaprojects, and lists a number of reasons for cost and schedule overruns.

Application of Microsoft Kinect Sensor for Tracking Construction Workers

The image processing based human recognition is yet a challenging task because of series of complications such as variations in pose, lighting conditions and complexity of background in the tracking environment. This study introduces a novel methodology to track construction workers using image processing techniques and depth information generated from the Microsoft Kinect sensor. Kinect is a new game controller technology introduced by Microsoft in November 2010. This automated real-time worker tracking system provides an opportunity to track the construction worker location and their movements in a specified indoor work area. The research study proposes a properly color coded “construction hardhat” as a key tracking object which can be used to differentiate site personnel (worker, supervisor, engineer, etc.). The proposed method detects construction workers in three major stages which includes human recognition, hardhat recognition and 3D localization. The human recognition is done by analysing human body parts. 3D positions of body joints are accurately predicted from a single depth image. The construction hardhat detection is based on characteristics of the hardhat such as unique shape and color. Template based template matching is used as the pattern recognition technique.

Prediction models for sewer infrastructure utilizing rule-based simulation

Management of infrastructure projects is becoming increasingly challenging due to inherent uncertainties. The most effeective way to deal with uncertainty is to collect supplementary information and knowledge. When expensive or infeasible, quantification of uncertainty may be performed using analytical or simulation techniques. The City of Edmonton, Canada has approximately 4600 km of sewer pipes in the combined, sanitary, and storm sewer local systems with uncertainty issues related to deterioration. The City has taken a proactive approach with respect to sewer rehabilitation, as it is more cost-effeective to repair a defective pipe prior to failure rather than after a collapse. This article demonstrates an approach for predicting the condition of a sewer pipe and the related cost of rehabilitation, given the limited data. Three models are described in this article that are developed to assist the City of Edmonton to effeectively plan maintenance expenditure. Each model uses a combination of rule-based simulation and probability analysis to assist in the planning of future expenditures for sewer maintenance, thereby producing an invaluable planning tool. Tel.: 780-440-7188, E-mail: ashraf.el-assaly@ue-1.com Tel.: 403-220-6892; E-mail: janaka@ucalgary.ca

CEPM 4: optimization of the waste management for construction projects using simulation

Growth in construction activities increases the amount of construction waste generated. Recycling of construction waste is an important component of environmentally responsible construction, as it reduces the amount of waste directed to landfills. In addition, it enhances the resource recovery for future construction work. A model is presented in this paper to predict waste generation rates, as well as to determine the economic advantages of recycling at construction sites. A future advanced version of the model can be applied to any construction site to: determine the amount of daily waste generation, resource and time requirement for sorting and transporting of recyclables. The model, therefore, is a valuable tool for construction managers interested in asserting the viability of recycling projects.

A novel solution for construction on-site communication - the information booth

A recent study on construction productivity improvement at the University of Calgary revealed the direct tool time (working time) of Alberta’s commercial construction to be about 51%. This study exposed inadequate communication and unavailability of required information as the main causes for a relatively lower tool time. Use of information technology (IT) to overcome widely visible communication issues was extremely limited at the construction site level. Construction companies’ hesitation to adopt new technologies was well noted whereas construction workers expressed their willingness and ability to use IT at the site level. The objective of this paper is to discuss the concept and the application of a novel communication tool (called an information booth) developed and pilot tested at a construction project. The concept and the technology presented in this paper have been tested at an actual construction project resulting in improvements in construction productivity, worker satisfaction, and efficiency...

Optimization of traffic signal light timing using simulation

Traffic congestion is one of the worst problems in many countries. Traffic congestion wastes a huge portion of the national income for fuel and traffic-related environmental and socioeconomic problems. Computer simulation is a powerful tool for analyzing complex and dynamic scenarios. It provides an appealing approach to analyze repetitive processes. Simulation helps decision makers identify different possible options by analyzing enormous amounts of data. Hence, computer simulation can be used effectively to analyze traffic flow patterns and signal light timing. This paper discusses a special-purpose simulation (SPS) tool for optimize traffic signal light timing. The simulation model is capable of optimizing signal light timing at a single junction as well as an actual road network with multiple junctions. It also provides signal light timing for certain time periods according to traffic demand. Traffic engineers at the University of Moratuwa, Sri Lanka are testing the developed tool for actual applications.

Evacuation behaviour of households and drivers during a tornado

Abstract With increasing concerns over the possibility of tornadoes in highly populated areas in Canada, emergency managers are looking into ways to mitigate the impacts of tornadoes. Given that tornadoes can cause enormous destruction, early warnings and proper evacuation actions are critically important in helping save lives. In this paper, a survey was conducted to analyse the evacuation behaviour of households and drivers during a hypothetical tornado warning situation in the city of Calgary, Alberta. Nearly 500 Calgarians took part in the online survey and provided information on how they would respond to tornado warnings after receiving them. This paper presents the results of the survey. Using probit models, the factors influencing these evacuation decisions are identified and discussed in detail. The results of the household evacuation model show the importance of improving awareness about the safest locations during a tornado. It further highlights the need for targeting the population under the age of 30, who are more likely to take unsafe evacuation actions. The model for evacuation of drivers shows that several factors, such as knowing the difference between a watch and a warning, awareness of safe cover, receipt of warnings through natural environmental cues and the level of education, trigger evacuation actions in avoiding a tornado threat.

AUTOMATED DATA ACQUISITION SYSTEM TO ASSESS CONSTRUCTION WORKER PERFORMANCE

This paper presents a real time and fully automated system using signal processing techniques for data extraction from digital video images, audio files and thermal images of construction work activities. This data extraction system is developed to detect the construction workers and their movements within a given work area to measure tool time and to assess worker productivity. The worker tracking system is based on the characteristics of the hardhat extracted from digital videos to differentiate worker from others such as supervisors and engineers. Furthermore, the work status of the worker is tracked using Infrared cameras and unidirectional microphones. Thermal images extracted from infrared cameras recognize whether the worker is working or idle. The audio files from the microphones identify the sound wave patterns of the worker tools. This real time and automated information is expected to measure the tool time and productivity of a given work within a specific time period. The information extracted and analysed from the system will certainly aid the project managers to better plan to optimize labor and crews to achieve the expected productivity.