Showing papers in "Journal of Computing in Civil Engineering in 2009"

Visualization of construction progress monitoring with 4D simulation model overlaid on time-lapsed photographs

Abstract: The ability to effectively communicate progress information and represent as-built and as-planned progress discrepancies are identified as key components for successful project management that allow corrective decisions to be made in a timely manner. However, current formats of reporting (e.g., textual progress reports, progress curves, and photographs) may not properly and quickly communicate project progress. Current monitoring methods also require manual data collection and extensive data extraction from different construction documents, which distract managers from the important task of decision making. Therefore, to facilitate progress monitoring, this paper proposes visualization of performance metrics that aims to represent progress deviations through superimposition of four-dimensional (4D) as-planned model over time-lapsed photographs in single and comprehensive visual imagery. As a part of the developed system, registration of the 4D model with photographs, augmenting photographs, and occlusion removal for progress images are presented. While contextual information is preserved, the as-built photographs are enhanced and augmented with 4D as-planned model in which the performance metrics are visualized. The augmented photographs provide a consistent platform for representing as-planned, as-built, and progress discrepancies information and facilitate communication and reporting processes.

Methodology for Automating the Identification and Localization of Construction Components on Industrial Projects

Abstract: Even though engineered components, such as pipe spools and structural steel elements, generally account for a significant percentage of the total installed cost of an industrial project, current industry practices still rely on human ability to track thousands of these components individually after they are received at the job site. These site-tracking practices are inefficient and error prone. This paper presents an approach for automating the identification and localization of construction components on large industrial projects. The proposed approach combines advanced sensing devices and localization mechanisms. The appropriate combination of global positioning system and radio-frequency identification (RFID) facilitates an infrastructure-free data collection process capable of detecting a large number of RFID-tagged components in short amounts of time. Based on the collected data, localization mechanisms precisely estimate the coordinates of the tagged components. Field experiments on real construction scenarios demonstrated the feasibility of the proposed methodology.

Automated Recognition of 3D CAD Objects in Site Laser Scans for Project 3D Status Visualization and Performance Control

Abstract: This paper presents a new approach that allows automated recognition of three-dimensional (3D) computer-aided design (CAD) objects from 3D site laser scans. This approach provides a robust and efficient means to recognize objects in a scene by integrating planning technologies, such as multidimensional CAD modeling, and field technologies, such as 3D laser scanning. Using such an approach, it would be possible to visualize the 3D status of a project and automate some tasks related to project control. These tasks include 3D progress tracking, productivity tracking, and construction dimensional quality assessment and quality control. This paper provides an overview of the developed approach and demonstrates its performance in object recognition and project 3D status visualization, with data collected from a construction job site.

Visualization and Simulation of Asphalt Concrete with Randomly Generated Three-Dimensional Models

Abstract: The objective of this study is to visualize and simulate microscale properties of asphalt concrete with three-dimensional discrete element models under mechanical loading. The microstructure of the asphalt concrete sample was composed of three ingredients: coarse aggregates, sand mastic (a combination of fines, fine aggregates, and asphalt binder), and air voids. Coarse aggregates were represented with the irregular polyhedron particles which were randomly created with an algorithm developed for this study. The gaps among the irregular particles were filled with air voids and discrete elements of sand mastic. The mechanical behaviors of the three ingredients were simulated with specific constitutive models at different contacts of discrete elements. Based on the geometric and mechanical models, visualization and simulation of asphalt mixtures were conducted in this study.

Technological Assessment of Radio Frequency Identification Technology for Indoor Localization

Abstract: Indoor localization is needed for guiding people who are not familiar with a facility. This need is more critical when guidance is needed to locate people or objects that need immediate attention. For example, an inexperienced facility worker might need to locate a building component (e.g., leaking pipe) for repair to prevent any damage to a facility or its residents. In such situations, an approach that can help the user to reach his/her destination point (i.e., a component of interest or a specific location in a facility) based on his/her current location is desired. To provide such guidance, the location of a person needs to be determined at a given point in time. This process is known as localization. The objective of this research study is to determine the technological viability of using radio frequency identification (RFID) to support localization. To assess the capability of RFID for localization, the writers conducted multiple field tests under real operating conditions within a facility at Carne...

Comparison of Optical Sensor-Based Spatial Data Collection Techniques for Civil Infrastructure Modeling

Abstract: Infrastructure modeling refers to the process of collecting infrastructure spatial data and transforming them into structured representations. It is useful during all stages of the infrastructure life cycle, and plays an important role in infrastructure's development and rehabilitation applications. In order to facilitate infrastructure modeling, a variety of optical spatial data collection techniques are available. None of them is ideal for all infrastructure applications. Each has its own benefits and limitations. The main purpose of this paper is to select an appropriate technique based on the given infrastructure application requirements. To achieve this goal, the principles of these techniques are first investigated. Their benefits and limitations are identified by comparing them in aspects such as accuracy, automation of spatial data retrieval, instrument cost, and portability. This way, the relationships between techniques and the requirements of civil infrastructure applications are established and compiled in tables. Practitioners can easily select an appropriate technique for their own applications by consulting these tables.

Dynamic Site Layout Planning Using Approximate Dynamic Programming

Abstract: Dynamic site layout planning requires identifying and updating the positions of all temporary construction facilities such as offices, storage areas, and workshops over the entire project duration. Existing models do not guarantee global optimal solutions because they focus on optimizing the planning and layout of successive construction stages in a chronological order, without considering the future implications of layout decisions made in early stages. This paper presents the development of an approximate dynamic programming model that is capable of searching for and identifying global optimal dynamic site layout plans. The model applies the concepts of approximate dynamic programming to estimate the future effects of layout decisions in early stages on future decisions in later stages. The model is developed in three main phases: (1) formulating the decision variables, geometric constraints, and objective function of the dynamic site layout planning problem; (2) modeling the problem using approximate dynamic programming; and (3) implementing and evaluating the performance of the model. An evaluation example is analyzed to illustrate the use of the model and demonstrate its capabilities in generating global optimal solution for dynamic site layout planning of construction projects.

Three-Dimensional Simulation and Visualization of Crane Assisted Construction Erection Processes

Abstract: A system for three-dimensional simulation and animation of erection processes is presented. The system is aimed at providing detailed planning and visualization in a virtual construction environment as well as for assisting crane operators in real-time during erection. In the system, construction cranes are modeled and treated as robots in which the motion required for each degree of freedom of the crane is computed as a function of the path to be followed by each component being erected. The sequence and path of each component are computed such that construction times are minimized and collisions with previously erected components are avoided. A physics-based simulation and animation of crane motions was also developed to visualize vibrations induced by crane motion. A special emphasis is placed on crane maneuvering required for containing motion-induced vibrations at acceptable levels and for increasing safety at job sites. Examples of the erection of steel and precast reinforced concrete buildings using tower cranes and crawler cranes are included. The system is a significant step forward in computer-assisted construction erection, for both prior to and during construction.

Distributed Augmented Reality for Visualizing Collaborative Construction Tasks

Abstract: Augmented reality is a visualization method in which virtual objects are aligned with the real world and the viewer can interact with the virtual objects in real time. In this paper, a new methodology called distributed augmented reality for visualizing collaborative construction tasks (DARCC) is proposed. Using this methodology, virtual models of construction equipment can be operated and viewed by several operators to interactively simulate construction activities on the construction site in augmented reality mode. The paper investigates the design issues of DARCC including tracking and registration, object modeling, engineering constraints, and interaction and communication methods. The DARCC methodology is implemented in a prototype system and tested in a case study about a bridge deck rehabilitation project.

Implementing metric operators of a Spatial Query Language for 3D Building Models: Octree and B-Rep approaches

Abstract: A spatial query language for building information models enables the spatial analysis of buildings and the extraction of partial models that fulfill certain spatial constraints. Among other feature...

Flight Optimization Algorithms for Aerial LiDAR Capture for Urban Infrastructure Model Generation

Abstract: Aerial light detection and ranging (LiDAR) offers the potential to autogenerate detailed, three-dimensional (3D) models of the built environment in urban settings. Autogeneration is needed as manual generation is not economically feasible for large areas, and such models are needed for a wide range of applications from improved noise and pollution prediction to disaster mitigation modeling and visualization. Current laser scanning hardware and the dense geometry of urban environments are two major constraints in LiDAR scanning. This paper outlines the difficulties related to effective surface data capture, with emphasis on vertical surfaces, in an urban environment for the purpose of 3D modeling. A flight planning strategy to overcome these difficulties is presented, along with a case study of a data set collected with this strategy. The main conclusions of this study are that an appropriate amount of strip overlap, together with a flight path diagonal to the underlying street grid produces a vastly enhanced level of detail on vertical surfaces, beyond what has been previously available.

Model for the 3D Location of Buried Assets Based on RFID Technology

Abstract: As construction and renovation equipment excavate in the vicinity of utility lines, the buried infrastructure is likely to suffer some form of “attack,” be that simple mechanical abrasion or a majo...

Reliability-Based Optimal Design of Truss Structures Using Particle Swarm Optimization

Abstract: In this work, the particle swarm optimization method is employed for the reliability-based optimal design of statically determinate truss structures. Particle swarm optimization is inspired by the social behavior of flocks (swarms) of birds and insects (particles). Every particle's position represents a specific design. The algorithm searches the design space by adjusting the trajectories of the particles that comprise the swarm. These particles are attracted toward the positions of both their personal best solution and the best solution of the swarm in a stochastic manner. In typical structural optimization problems, safety is dealt with in a yes/no manner fulfilling the set of requirements imposed by codes of practice. Considering uncertainty for the problem parameters offers a measure to quantify safety. This measure provides a rational basis for the estimation of the reliability of the components and of the entire system. Incorporating the reliability into the structural optimization framework one can seek a reliability-based optimal design. For the problems examined herein, the reliability indexes of the structural elements are obtained from analytical expressions. The structure is subsequently analyzed as a series system of correlated elements and the Ditlevsen bounds are used for the calculation of its reliability index. The uncertain-random parameters considered in this work are the load, the yield-critical stress; and the cross sections of the elements. The considered design variables of the optimization problem are the cross-sectional areas of the groups, which control the size of the truss, and the heights and lengths that control the shape of the truss. The results of the optimization are presented for a 25-bar truss and a 30-bar arch and the robustness of the optimization scheme is discussed.

Optimizing Large-Scale Temporary Housing Arrangements after Natural Disasters

Abstract: Natural disasters, such as hurricanes, earthquakes, and tsunamis often cause large-scale destruction in residential areas. In the aftermath of these disasters, emergency management agencies need to urgently develop and implement a temporary housing plan that provides displaced families with satisfactory and safe accommodations. This paper presents the computational implementation of a newly developed multiobjective optimization model to support decision-makers in emergency management agencies in optimizing large-scale temporary housing arrangements. The model is capable of simultaneously minimizing 1 postdisaster social and economic disruptions suffered by displaced families; 2 temporary housing vulnerabilities to postdisaster hazards; 3 adverse environmental impacts on host communities; and 4 public expenditures on temporary housing. The model is implemented in four main phases and it incorporates four optimization modules to enable optimizing each of the aforementioned important objectives. A large-scale temporary housing application example is presented to demonstrate the unique capabilities of the model and illustrate the performed computations in each of the implementation phases.

Embedded System for Construction Asset Tracking Combining Radio and Ultrasound Signals

Abstract: Today's sensor technology provides the increased opportunities for automation and improvement in data acquisition and construction processes. However, many current field practices at construction sites still rely on manual processes for asset tracking and information handling. Previous technologies, such as radio frequency identification and global positioning systems, do not provide a solution to automated asset tracking because of their limitations in terms of applicability and performance in a typical construction environment. This paper introduces a new development of an embedded sensor system for construction asset tracking by combining radio and ultrasound signals. We present the detailed hardware and software architecture and have implemented outdoor experiments to examine the accuracy and performance of the designed system. The results obtained showed the accurate distance and position estimation with enhanced networking flexibility. The findings and lessons learned from this research demonstrate the potential for future practical deployment of similar systems in many civil engineering applications.

Integrating Construction Operation and Context in Large-Scale Construction Using Hybrid Computer Simulation

Abstract: This research proposes a hybrid simulation approach based upon the principles of system dynamics (SD) and discrete event simulation (DES), which facilitates a better understanding of complex interactions among various processes in large-scale construction. The significance of the construction context that interacts with construction operations is highlighted, and a hybrid SD-DES approach is proposed as a means to capture the feedback between the two. In particular, this paper focuses on how to seamlessly integrate SD and DES within the framework of a modeling perspective. For the purpose of substantiating the discussion, a pipeline installation process is modeled using the proposed hybrid approach, with specific consideration given to how the approach can serve to address complex interactions between operation and context.

Automated Generation of Operations Level Construction Animations in Outdoor Augmented Reality

Abstract: Three-dimensional (3D) visualization is an effective tool for communicating, verifying, and validating the results of a simulated operation. Traditional visualization tools used for this purpose are typically based on the paradigm of virtual reality. Augmented reality (AR) is a relatively newer visualization paradigm whose engineering applications have been explored by a limited number of researchers. In this paper, the problem of generating smooth and continuous AR animations from the results of running discrete event simulation models and a general purpose methodology to overcome this challenge are discussed. The structure of an AR animation authoring language developed by the writers to create a logical link between a running simulation model and its corresponding 3D visualization in AR is described. In order to validate the functionality and effectiveness of the designed methods and animation language, an AR-based visualization application was developed and the designed algorithms were successfully tested using different simulation scenarios of varying visual and operational complexity.

Visual Pattern Recognition Supporting Defect Reporting and Condition Assessment of Wastewater Collection Systems

Abstract: Computational approaches to visual data and information processing can assist asset management procedures. In this paper, we present a computerized visual pattern recognition approach to facilitate inspection and condition assessment of wastewater collection systems in realistic settings. This research aims to provide a basis for condition assessment and defect reporting in wastewater infrastructure, enabling automatic detection and recognition of defects and patterns from inspection images or videos. An approach for sensing and automatically detecting critical areas or regions of interest, and further discovering and recognizing objects of interest in large image data sets, is described. The major steps of the approach are illustrated by examples using actual inspection images acquired from wastewater pipelines.

Unique Requirements of Building Information Modeling for Cast-in-Place Reinforced Concrete

Abstract: The building information modeling (BIM) tools that have matured for structural steel and precast concrete construction are not suitable for production modeling of cast-in-place (CIP) reinforced concrete structures. The main reason is that CIP structures are monolithic in nature, as opposed to the discrete objects that are typical of steel and precast. A consortium of 12 major contractors and design firms collaborated over a one-year period to formulate the functional requirements for development of a BIM tool for cast-in-place reinforced concrete. The functional requirements were derived from a process model used to scope and understand the processes surrounding reinforced concrete design and production. The functional requirements were finally expressed as a set of object schemas, defining relations, methods, and attributes needed. These are essential for software companies to incorporate in their BIM tools to provide for the unique needs of modeling CIP structures.

Generalized Traffic Sign Detection Model for Developing a Sign Inventory

Abstract: The hundreds of traffic sign types on the road and their various shapes and colors make it difficult to develop a generalized method of traffic sign detection. Consequently, agencies performing a sign inventory must manually review millions of roadway video log images. This paper proposes an innovative image processing model that automatically detects traffic signs and dramatically reduces the sign inventory workload. In a test of the proposed model using 37,640 images provided by the Louisiana Department of Transportation and Development, 86 percent of the manual review efforts can be effectively saved. Our method is composed of (1) a generalized traffic sign model to represent the entire class of traffic signs; (2) a proposed new statistical traffic sign color model; (3) a traffic sign region of interest detection system using polygon approximation; and (4) traffic sign candidate decision rules based on shape and color distributions.

Incorporating Domain Knowledge and Information Retrieval Techniques to Develop an Architectural/Engineering/Construction Online Product Search Engine

Abstract: This paper introduces a domain-specific search engine, which was developed to take advantage of the growing online product information for surveying the virtual product market. Knowledge about a product was uniquely incorporated with query expansion operations and the extended Boolean model retrieval approach to handle issues associated with the search engine development. The search engine was designed to (1) represent and utilize the represented knowledge in the product domain; (2) identify online product information; and (3) then evaluate the collected online product information. A prototype search engine for testing was developed and statistically validated with five data sets with each data set being derived from a different type of product according to MasterFormat (Alexandria, Va.) categorization. The validation results indicated that compared with the tested general search engine or aggregated information service, the prototype was able to identify more distinct product manufacturers for procurement-related decision support.

Application of adaboost to the retaining wall method selection in construction

Abstract: The appropriate selection of construction methods is a critical factor in the successful completion of any construction project. Artificial intelligence techniques are widely used to assist in the selection of a construction method. This paper proposes the use of the adaptive boosting (AdaBoost) model to select an appropriate retaining wall method suitable for particular construction site conditions, in order to examine the applicability of AdaBoost in construction method selection. To verify its applicability, the proposed model was compared with a support vector machine (SVM) model, which have been attracting attention for their high performance in various classification problems. The AdaBoost model showed a slightly more accurate result than the SVM model in the selection of retaining wall methods, demonstrating that AdaBoost has advantages (e.g., robustness against defective data with missing values) in application to decision support systems. Moreover, the AdaBoost model can be used in future projects to assist engineers in determining the appropriate construction method, such as a retaining wall method, at an early stage of the project.

Modified harmony search algorithm and neural networks for concrete mix proportion design

Abstract: This study proposes a new methodology with harmony search (HS) algorithm and neural networks (NNs) for concrete mix proportioning. The basic procedure for the methodology consists of four steps: (1) constructing a database of mix designs; (2) establishing appropriate models for strength and workability; (3) optimizing mix proportion using the modified HS algorithm; and (4) refining the mixture using NNs. The proposed methodology could be a useful decision-making tool for concrete mix design.

Optimum Concrete Mixture Proportion Based on a Database Considering Regional Characteristics

Abstract: This paper presents an enhanced design methodology for optimal mixture proportion of concrete composition with respect to accuracy in the case of using prediction models based on a limited database. In proposed methodology, the search space is constrained as the domain defined by a limited database instead of constructing the database covering the region represented by the possible ranges of all variables in the input space. A model for defining the search space which is expressed by the effective region in this paper and evaluating whether a mix proportion is effective is added to the optimization process, yielding highly reliable results. To demonstrate the proposed methodology, a genetic algorithm, an artificial neural network, and a convex hull were adopted as an optimum technique, a prediction model for material properties, and an evaluation model for the effective region, respectively. And then, it was applied to an optimization problem wherein the minimum cost should be obtained under a given strength requirement. Experimental test results show that the mix proportion obtained from the proposed methodology considering the regional characteristics of the database is found to be more accurate and feasible than that obtained from a general optimum technique that does not consider this aspect.

Water Distribution Network Design Using Heuristics-Based Algorithm

Abstract: Water distribution network that includes supply reservoirs, overhead tanks, consumer demand nodes, interconnecting pipes, lifting pumps, and control valves is the main mode of water supply for majority of the communities especially in urban areas. Supply of required quantity of water and at right time is the primary objective of water distribution network analysis. The analysis of water distribution networks can be broadly classified into design and operation problems and both problems have been the focus of many researchers over the past three decades. In the water distribution network design problems, the target is attaining the cost effective configuration that satisfies the minimum hydraulic head requirement at the demand nodes. In this paper, a new algorithm for design of water distribution network namely "heuristics-based algorithm" which completely utilizes the implicit information associated with the water distribution network to be designed has been proposed and validated with two water distribution networks. It is found that the proposed algorithm performs well for the least-cost design of water distribution networks.

Concept-Based Method for Extracting Valid Subsets from an EXPRESS Schema

Abstract: An EXPRESS schema is a data schema defined in EXPRESS, an international standard language for defining product data schemas. This technical paper proposes and formally defines a set of conditions for generating a minimum valid subset of an EXPRESS schema corresponding to a concept, where a concept is a general idea and a subset is a partial model of a data schema. We introduce a notion of "minimal set" to define the relationships between a subset and other subsets, and also between a subset and concepts. A minimal set is the smallest complete subset of a schema that corresponds to a concept. Using IFC, an international standard data model for the architecture, engineering, and construction industry, the proposed conditions have been implemented in a software application developed for extracting subsets from the IFC schema matching the concepts. A number of examples are demonstrated.

IT Issues for the Management of High-Quantity, Low-Cost Assets

Abstract: Transportation infrastructure asset management efforts have historically focused on collecting data on assets with high capital costs, such as bridges and pavements. Road signs and pavement markings, on the other hand, are high quantity, low capital cost assets but are also critical elements of the transportation infrastructure. These high quantity assets serve a critical function, safety, and thus they are receiving attention. Mandated by law, the Federal Highway Administration has been working to establish minimum retroreflectivity standards for signs and pavement markings. This paper seeks to address the information technology (IT) problems that emerge when developing an overall asset management system for high-quantity, low-cost assets. These IT problems include asset identification, asset location, data availability, data fragmentation, and automated data collection. A discussion of the issues related to these problems is presented to promote awareness of the myriad problems that do exist and to facilitate the development of more comprehensive systems to manage the automation of infrastructure asset management systems.

Dimensional Analysis of Bridges from a Single Image

Abstract: Dimensional analysis from single images is still a fruitful topic for investigation, even if range sensors and stereo imaging technologies are becoming a common alternative to the generation of metric information. This paper describes the scientific approach developed for the dimensional analysis of bridges based on a single image. The basic dimensions of bridges are provided using a low-cost and flexible alternative that breaks with the classical stereoscopic photogrammetric principle. Several case studies are reported to demonstrate the novelty and real capabilities of this methodology.

Integrating Robot Mapping and Augmented Building Simulation

Abstract: This paper discusses a framework for integrated augmented reality (AR) architecture for indoor thermal performance data visualization that utilizes a mobile robot to generate environment maps. It consists of three modules: robot mapping, computational fluid dynamics (CFD) simulation, and AR visualization. The robot mapping module enables the modeling of spatial geometry using a mobile robot. In order to generate steady approximations to scanned three-dimensional data sets, the paper presents a novel "split-and-merge expectation-maximization patch fitting" (SMEMPF) planar approximation method. It allows for precise adjustment of patches independent from the initial model. The final result is a set of patches identifying planar macrostructures that consist of a collection of supported tiles. These patches are used to model the spatial geometry under investigation. The CFD simulation module facilitates the prediction of building performance databased on the spatial data generated using the SMEMPF method. The AR visualization module assists in interactive and immersive visualization of CFD simulation results. Such an integrated AR architecture will facilitate rapid multiroom mobile AR visualizations.

Modeling and Visualization of Underground Structures

Abstract: Based on the solid modeling, transformation operation and Boolean operation techniques widely available in computer-aided design and drafting system, first, this paper proposed a general modeling method for dynamic underground structure simulation. Then, representations of underground structures, ground, and related information in three-dimensional space were investigated. Some suggestions were put forwarded to improve visualization results, including object organization by layers, thematic viewing, level of detail for object representation, and spatial cueing for useful information. Application examples were given to illustrate the visualization effects. Finally, virtual reality technology was employed in the simulation of the underground structures. By positioning objects using real-time information, picking objects, and then accessing their real world working status through the Internet, the realistic results of a virtual system were further discussed. It has also been found that in order to obtain satisfactory visual results using an inexpensive desktop computer, a virtual reality model must be optimized from the perspective of reducing object complexity as well as efficient scene management.