Ming Lu

University of Alberta | UAlberta · Department of Civil and Environmental Engineering and the School of Mining and Petroleum Engineering

Significant risks in project completion delay could be buried in the development of project schedules because of theoretical flaws in project schedule risk analysis. Major project delays hamper infrastructure development endeavors and cause negative consequences to project finance, the public interest, and socioeconomic growth. This research critic...

In this research, the multilayer perceptron (MLP), also known as error backpropagation neural networks, is made transparent and explainable by contrasting with the commonly applied multiple linear regression (MLR). A novel MLP-based method for performing global sensitivity analysis is formalized to tackle complicated, nonexplainable simulation mode...

The data used for productivity modeling represents a sample of a company's performance taken at a particular time, which leads to varying model parameters and results in a variance of the predicted productivity. This research enhances the capability of the nonlinear machine learning method called Model Tree by integrating error propagation theory t...

Model trees combine the strengths of two interpretable models-namely, decision trees and multiple linear regression-to handle complex nonlinear problems, making them a popular machine-learning strategy in civil engineering. Analyzing the error terms between predicted and target outputs is the standard method for evaluating the model's accuracy. How...

The growing concern for occupational health and safety in construction is reflected in many preventive measures taken against the risks associated with hazardous activities. However, methods for systematic assessment of hazards and risks are not straightforward to apply or lacking consistency. This paper proposes a method for risk index evaluation...

In a practical context of construction management, a number of special contractors are selected to deliver a multiproject program in a definitive time frame. Research has yet to address how well contractors are matched to projects in scheduling and how to evaluate this criterion in scheduling optimization analysis. This research formulates a novel...

Regression modeling has been based on analyzing error terms between the predicted output and the target output without addressing the variance of the predicted output and the impact of individual input parameters on the variance. This research critically reviews established methods for variance analysis on commonly applied multiple linear regressio...

Accurately modeling productivity is essential for ensuring that the results of construction process simulation models align with actual practice. Since collecting quantitative data is challenging and expensive, productivity models are often built using the information provided by industry experts. The subjectivity of this information, however, comm...

Purpose Previous research regarding shaping factors and major causes behind accidents in the construction field is reviewed. In particular, a hypothetical model is established to correlate activity time, cost and safety in the context of construction activity acceleration planning. Two demonstration cases are presented to illustrate the proposed th...

The existence of multiple optimum solutions in project Time-Cost Tradeoff (TCT) optimization has not been seriously researched, while the demand on computing time and resources considering project network models of practical size has not been benchmarked. To a certain degree, this has accounted for (1) the lack of commercial software in the market...

A novel labour-hour budgeting method is proposed by integrating productivity concepts in project scheduling and budgeting to enhance the accuracy of labour cost budgeting for planning labour-intensive projects. The proposed method applies discrete event simulation approach to represent crew formation, labour resource utilization, and labour resourc...

The logic of an artificial intelligence (AI) model derived from machine learning algorithms and domain-specific data is analogous to an expert’s perception of a complex problem. Human insight based on know-how and experience also provides the best clue to verify such analytical models generalized from data. To facilitate the acceptance and implemen...

The model tree algorithm of M5 is integrated with the multiple linear regression technique called modified stepwise regression (MSR), resulting in a new method for modeling complex civil engineering problems. We purposefully chose artificial neural networks (ANN) for comparison against the proposed “M5+MSR” because they fall at the two ends of the...

Industrial construction employs various trades in large-scale prefabrication operations to produce modules and structural components at an offsite facility that will be shipped to the field for rapid installation. Developing an analytical methodology for characterizing the effect of variability in productivity on labor cost budgeting is vital to th...

Time, cost and safety are essential elements in planning a construction project. A cost-effective project planning method is desired to reduce project cost and duration, while maintaining an acceptable safety level. Although there are many studies addressing safety management and time-cost trade-off optimization separately, less attention has been...

This research investigates resource inter-activity utilization efficiency arising from resource shared use and transfer observed in planning projects at a structural steel fabrication shop. Aided with discrete event simulation-based resource-constrained scheduling analysis, the necessity of defining the resource inter-activity utilization efficienc...

The problem of planning drainage services in a certain timeframe by a typical municipal infrastructure maintenance organization lends itself well to existing solutions for resource constrained project scheduling optimization. However, the optimized schedule could be deemed insufficient from a practitioner's perspective as the very crucial soft cons...

To facilitate knowledge representation and transfer, this research explores the feasibility of implementing the machine learning technique of model trees in a practical application setting. In collaboration with a steel fabricator company in Canada, we tapped into the mental model of experienced estimators in the steel fabrication domain by analyzi...

Structural steel prefabrication is a generally accepted practice in the construction industry conducive to better control of project duration and cost, higher productivity and efficiency, and enhanced quality and safety performance. This study initiated with an investigation of the current practice of major structural steel fabricators in Alberta,...

This paper addresses a practical planning problem in bridge steel girder fabrication in an attempt to illuminate why the identified problem does not lend it well to existing solutions for construction planning. A simulation-based approach is presented for project scheduling and production planning at a structural steel fabrication shop. The shop si...

In modular and offsite construction, structural components are prefabricated in a fabrication shop resembling a manufacturing plant in order to accelerate field construction processes. However, the dynamic nature of such fabrication operations often demands frequent adjustments to original production plans so as to fit actual project start-finish s...

This paper describes a dynamic simulation application in modeling complex workflows of a bridge girder fabrication shop based on a three-tiered modeling framework. The objective of this framework is to produce straightforward, adaptive simulation models that can sufficiently represent essential operational details on the shop floor from the perspec...

In theory, time-cost tradeoff (TCT) analysis is a classic planning problem appealing to construction management; yet, existing analytical methods are found inadequate to make a significant impact in practice. Heuristic methods lack a theoretical basis to ensure arriving at optimum solutions in solving specific problems; on the other hand, mathemati...

Predicting remaining useful life (RUL) of critical machines in heavy maintenance industries, such as oil refineries and upgrading, is crucial to deliver robust and cost-effective plans for resource procurement and maintenance scheduling in a challenging and constrained work environment. Statistical methods have been extensively utilized based on co...

Predicting remaining useful life (RUL) of critical machines in heavy maintenance industries, such as oil refineries and upgrading, is crucial to deliver robust and cost-effective plans for resource procurement and maintenance scheduling in a challenging and constrained work environment. Statistical methods have been extensively utilized based on co...

One limitation of previous productivity-driven research on equipment selection and operation simulation lies in the fact that the green aspects of construction activities have been largely neglected in analysis of cost-efficiency of construction operations. On the other hand, studies attempting to measure greenhouse gas emission due to construction...

To promote mixed-integer linear programming (MILP) in engineering applications, it is vitally important to address the question: To what extent is the optimum solution of MILP able to tolerate variations and changes in certain model parameters and still hold valid? This paper has formalized a generic methodology for identifying parameter stability...

Cutting rebar stocks to fit to specific requirements of designed structural components on a construction project results in cutting losses, which is the major contributor to the generation of construction waste. Previous research developed mathematical models to analytically minimize rebar cutting losses, but without integrating engineering design,...

This research is intended to improve the current practice of resource planning and project scheduling at a prefabrication facility in construction, where engineered systems or components of large size and heavy weight are fabricated for multiple concurring projects with limited workplace and storage areas. A dual-level multiproject scheduling frame...

Assigning labour-hours to a certain scope of work during design and estimating is still more of an art than a science. This research proposes a data-driven approach that uses multiple linear regression (MLR) and available historical data from building information models (BIM) to associate project labour-hours and project design features. The framew...

Extensive research in automated operation planning has led to significant advances in the area of robotics. Theories and methods resulting from robotics have yet to be adapted to enable automated project planning in construction engineering. Aiming to demonstrate the potential of implementing automated planning theory and methods in construction pr...

With increasing implementation of off-site prefabrication and modular construction technologies, the complexity of material supply chain management on construction projects has grown substantially. However, research on construction scheduling has yet to take dynamic material logistics as an explicit constraint in analytically deriving construction...

Accuracy in cost estimating is one of the principal challenges the construction industry currently faces. Many strategies, software, and techniques have been developed to mitigate the tremendous financial losses produced by such deficiency. A study that compares the strengths and weaknesses in the utilization of Uniformat (UF) and Masterformat (MF)...

This paper introduces the sensor equipped backhoe excavator which is capable of tracking its bucket tip with respect to its base and functioning as a mobile survey robot. The new approach for precise position tracking of the excavator's bucket tip can be used to plan the operation trajectory of the excavator's arm to streamline its movement and tra...

Technologies for information management and visualization are instrumental in enhancing human perceptions and interpretations of complicated project information. 3D/4D modeling, Virtual Reality (VR), Building Information Models (BIM) and Geographical Information Systems (GIS) have been increasingly used for data management and analytics in construc...

Uncertain ground conditions, confined working space, high turnover rate of specialized construction crews increase safety hazards and risks in tunneling. This paper discusses the importance of devising up-to-date and cost-effective adaptive training programs upon enhancing construction safety in tunneling. An adaptive framework is proposed for cust...

Building information modelling technology provides a game-changing solution to address the challenges encountered in the AEC industry. However, this technology currently is not sufficient to fulfil the needs of construction practitioners in terms of proactive design and planning for boarding of light-frame residential buildings. This is partially d...

Background As offsite prefabrication and modular construction continue to gain momentum into the future, material supply chain becomes increasingly complex for modern construction projects. Pre-engineered material supply presents itself as a driver for planning crew installation operations on site that involve skilled labor and heavy equipment. Me...

In practice, RSMeans (2016) and Caterpillar Performance Handbook (Caterpillar 2016) are the two most widely accepted sources of construction productivity and cost benchmark data in the heavy construction industry. In general, CAT Handbook provides detailed time data for equipment cycle and its main steps given particular categories of equipment and...

This paper describes an analytical model along with a visualizing tool, based on the error propagation theory to quantify and visualize the uncertainty that is present in the position and pose of the excavator obtained from sensor-based measurements regardless of the type of sensors used. A technique is also presented to aid in the selection proces...

Structural steel is heavily utilized in the construction industry from residential and commercial buildings to oil and gas projects. For steel fabrication companies as suppliers of steel structures, submitting competitive project bids requires substantial knowledge of the company's practices on the shop floor and extensive experience to interpret t...

Reinforced steel rebar is commonly supplied in one-dimensional stocks and typically designed for and installed in various structural components in civil and industrial construction. Surplus reinforcement constitutes a major fraction of construction generated waste. Cutting one-dimensional stocks to suit construction project requirements results in...

A literature review has identified the absence of a robust framework that guides the development of streamlined and valid multiple linear regression (MLR) predictive models for construction engineering applications. A reliable MLR model requires an appropriate set of input variables that can satisfy the underlying assumptions of best linear unbiase...

Temporary haul road plays a pivotal part in achieving cost-efficiency and successful project delivery in heavy civil and industrial construction. Temporary haul road layout design has been empirically performed by field managers, superintendents or even truck drivers largely based on experience instead of science. Previous research endeavors in ear...

The classic critical path method (CPM) determines total float (TF) for each individual activity by performing forward pass and backward pass analyses. A comprehensive literature review has shown that TF is the most crucial attribute of a scheduled activity, and plays a fundamental part in advanced scheduling research. This research proposes a simpl...

The present research proposes an analytical methodology to automatically generate a work breakdown structure (WBS) and a project network model based on activity-on-node (AON), which consists of two stages: (1) optimizing earthwork volume allocation, which is intended to define haul jobs by identifying the most economical combinations of cut and fil...

Engineering design of a drainage tunnel specifies start/end positions, alignment, grades, and tunnel diameter/lining material. Tunnel construction faithfully transforms engineering design into the built structure in the underground space. In construction, the guidance system of the tunnel boring machine (TBM) is crucial to ensure all design specifi...

Temporary haul roads are typically designed and constructed to handle mass earthworks in heavy civil and industrial construction, critical to achieving haulage efficiency and safety in earthmoving operations. Traditional temporary haul road layout design has long been based on experience rather than science. Previous research endeavors developed ma...

In building information modelling (BIM), the model is a digital representation of physical and functional characteristics of a facility and contains enriched product information pertaining to the facility. This information is generally embedded into the BIM model as properties for parametric building objects, and is exchangeable among project stake...

Temporary haul roads are typically designed and constructed to handle mass earthworks in heavy civil and industrial construction, critical to achieving haulage efficiency and safety in earthmoving operations. Traditional temporary haul road network design has long been based on experience rather than science. Previous research endeavors developed m...

Assessment of budget sufficiency and resource utilization for a resource-constrained project schedule is crucial to ensure practical feasibility of the schedule and successful delivery of a construction project. This paper proposes a quantitative assessment approach for characterizing budget sufficiency and resource utilization for a resource-const...

This paper discusses a novel approach for resource-based scheduling that builds upon existing analytical models to achieve practical allocation of resources that are constrained by supply and demand. The approach facilitates workface planning to allocate work to individual craft persons. The main contribution of the work is advancement of the curre...

Existing resource scheduling methodologies are insufficient for controlling workflows for individual craft persons in project and workface planning. In practice, the workflow of an individual resource is assigned by a project manager in consideration of the resource supply and resource demand for particular time periods of the project duration. Thi...

Practical Tunnel-boring Machine (TBM) guidance systems usually use sophisticated instruments to obtain the orientation of the TBM. These systems require frequent calibration and work shutdown, making the procedure complex and time consuming. Besides, the majority of current TBM guidance solutions cannot provide the position of the invisible cutter...

Panelization, a form of off-site construction with origins in the manufacturing industry, has emerged as a popular, more efficient approach to constructing residential projects. This approach transfers some of the construction activities traditionally carried out on site into factory production tasks, and divides construction management into factor...

Building information modelling (BIM) is an information technology that has the ability to change the Architecture, Engineering, and Construction (AEC) industry in terms of enhanced communication and productivity. With the rise of BIM, panelized/off-site construction is gaining momentum within the home building industry. However, BIM has not yet bee...

Skilled labor is critical to any construction project. The determination of optimum resource supply quantities over different project time periods compounds the resource-constrained project scheduling problem, which has yet to be formally formulated and analytically solved. Previous related research endeavors focused on the allocation of finite qua...

As a critical component of planning mass earthworks projects, designing effective haul road networks is conducive to delivering the project on time and under budget. The research reported in this paper proposes a grid-based temporary road network design method applicable to a site for which grading design has been completed. Further adding to the e...

This paper describes the implementation of an indoor positioning architecture based on radio frequency profiling using received signal strength (RSS) measurements for localizing and tracking resources in construction-related applications. The profiling-based approach is coupled with commonly used noise filtering algorithms in order to cope with the...

In a steel fabrication shop, jobs from different clients and projects are generally processed simultaneously in order to streamline processes, improve resource utilization, and achieve cost-effectiveness in serving multiple concurrent steel-erection sites. Reliable quantity takeoff on each job and accurate estimate of shop fabrication man-hour requ...

The critical path method (CPM) provides the standard approach to scheduling construction projects. Limited crew resources compound CPM analysis by imposing resource availability constraints. However, there is no generalized methodology yet to quantitatively determine the optimal quantities of resources to execute specific work packages based on CPM...

This research is intended to generate relevant and quantitative decision support based on limited data and information available in the context of planning earthmoving operations at the site-grading design or early project planning stage. The researchers apply and extend the concept of haul effort in a two-axis grid. This enables calculation of the...

Construction engineering and management research takes advantage of proven technologies and turns them into cost-effective solutions in the construction field. This paper describes our efforts in the development of a new alignment control and machine guidance system for tunnel-boring operations. Steering a tunnel boring machine (TBM) in tunnel proj...

By taking advantage of cost-effective technology and elegant computing algorithms, turning invisibility into transparency provides field crews with peace of mind and substantially improves controllability and efficiency of construction operations. In current practice, the as-built information of a tunnel is generally collected as a separate effort...

Effective positioning and tracking of critical construction resources is crucial to fulfilling project objectives in terms of time, cost, and safety. Received signal strength (RSS) based localization methods increasingly become a popular choice in construction applications, especially for indoor scenarios, potentially automating field data acquisit...

The lack of the expertise and resources, the unavailability of sufficient and complete operations data, and the absence of relevant site information present obstacles to applying combined simulation modeling in practice. Construction modelers are required to make critical decisions in a short turnaround time for planning operations and improving pr...

With the increasing popularity of Building Information Modeling (BIM), several research studies have focused on its application in the construction industry, and advancements such as developments of BIM-based tools for construction scheduling and cost estimating have been carried out. Nevertheless, these tools are each developed only for one partic...

It is vitally important to evaluate costs, benefits and risks associated with adopting a new method or technology prior to field implementation. The present research proposes a framework for estimating potential cost savings by implementing new method or technology in the field in terms of: (1) productivity-dependent crew cost; (2) time-dependent i...

The complexities inherent in scheduling the execution of process plant turnaround projects present distinctive challenges to project managers in identifying the shortest project duration while determining the optimum crew size. In collaboration with a major plant turnaround contractor in Alberta, we monitored the execution of an oil refinery turnar...

Congestion can restrict access to construction activities both on and close to a freeway, reducing construction efficiency, especially by delaying the delivery of materials. Although previous studies have investigated the impact of work-zone capacities on traffic flow, most did not consider interactions with construction resources. There is current...

Background Three-dimensional (3D) modeling and visualization of temporary site facilities is instrumental in revealing potential space conflicts and refining time and cost estimates. This research focuses on implementation of photo-based 3D modeling in a time-dependent, dynamically-changing context. Methods We propose a cost-effective modeling tec...

To fulfill the needs of construction quality, progress control and sustainable development of the underground space, it is desirable to collect and visualize as-built tunnel information in real time. In the current practice, the as-built model of a tunnel is produced either by using advanced technologies like 3D laser scanning after construction en...

Discrete event simulation (DES) produces models of greater granularity and higher accuracy in analysis of heavy construction operations than classic quantitative techniques; specifically utilizing average production rates for determining the fleet required for and duration of earthmoving operations. Nonetheless, the application of DES is not readil...

Plant shutdown and maintenance, commonly termed as the turnaround project in the industry, aims to ensure safe and reliable production of an existing oil refinery and to expand capacities of existing plant facilities. Subject to constraints such as fixed project period, limited total budget, earliest activity start times, confined working areas and...

Three-dimensional (3D) modeling of site elements is beneficial to many construction management applications such as quantity takeoff and quality control. However, current practice lacks a solution that is computationally simple, cost effective, and easy to use in the field. This research proposes a 3D modeling method based on the mechanism of photo...