Article

Evaluation of an Emerging Market in Subsurface Utility Engineering

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Abstract

Subsurface utility engineering SUE is a fast growing industry segment in the civil engineering arena. Subsurface utility engineering is gaining credibility as a significant tool to reduce the risk from informational uncertainty associated with underground facilities in a construction project. Subsurface utility engineering can minimize the risk primarily through mapping existing underground utility facilities, utilizing surface geophysical technologies, surveying and data management systems. This paper presents a comprehensive evaluation of SUE to facilitate a better understanding of this emerging industry by the many in the construction domain that are relatively unfamiliar with it. Topics investigated include quality levels in SUE, incorporation of SUE strategy at different stages in the construction project, and cost–benefit analysis of SUE based on 71 actual construction projects where SUE was employed. In addition, the results obtained from questionnaire surveys of State Departments of Transportation DOTs and the SUE industry are analyzed, which reveal the trend of state DOTs in the use of SUE and various aspects of SUE business in private sectors.

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... However, past research suggests these records may be outdated, incomplete, or erroneous, often leading to incorrect assumptions about utility positions (Anspach and Scott 2019;Jung 2009). According to studies, inaccurate utility data has contributed to numerous utility strikes over the past decade, resulting in injuries, fatalities, and substantial financial losses (Jeong et al. 2004;Kraus et al. 2012;Lew 2000). ...
... A key component of SUE involves assigning standardized Quality Levels (QLs) to utility data, ranging from low certainty QL D based on existing records to high accuracy QL A obtained from exposed and surveyed utilities (ASCE 38, 2022;FHWA, 2018). By leveraging advanced subsurface investigation techniques alongside traditional records, SUE aims to deliver utility mapping with minimized risk of unforeseen conflicts (Anspach 2019;Anspach and Scott 2019;Jeong et al. 2004;Lew 2000). ...
... SUE has become an indispensable engineering practice for mitigating utility-related risks caused by inaccurate and incomplete underground utility mapping (Anspach 2019;Jeong et al. 2004;Lew and Anspach 2010). The emergence of SUE over the past few decades provides a comprehensive framework of technologies and practices for identifying, locating, and mapping underground utilities to enable informed engineering design and construction (Anspach and Scott 2019;Kramer and Cady 2022;Sturgill et al. 2022) Core SUE practices include extensive research of existing utility records, site surveys to visually identify above-ground utility features, geophysical subsurface detection using techniques like ground-penetrating radar, and vacuum excavation to safely expose and directly measure underground utilities (Anspach and Scott 2019;ASCE 38 2022). ...
... Based on the observed savings and effectiveness of SUE, many state and federal agencies, such as the Federal Aviation Administration, the Department of Defense, the Department of Energy, the General Service Administration, and the Network Reliability Council, now include at least some SUE services for select projects (2,8). In addition to being used by the FHWA and state DOTs, SUE is currently being employed by numerous engineering firms (2). ...
... Therefore, these benefits can be quantified to account for and evaluate the cost savings of using SUE (2,8). Quantifying these benefits in the form of cost savings involves assuming a scenario in which the design and construction would take place without the implementation of SUE and accounting for the loss or extra funds that would be spent to cater to any form of utility conflict. ...
... The study recorded an average ROI of $4.62 for every $1 spent on using SUE (6). Further analysis of Lew's study by Jeong et al. showed an ROI of $12.23 for every $1 spent on SUE, with saving from reduced utility relocations accounting for 37.1% of all SUE savings (2,8). ...
Article
Since the late 1990s, studies conducted on the implementation of the subsurface utility engineering (SUE) concept in the design and planning phase of highway infrastructure projects have repeatedly shown a significant return on investment (ROI). ROI values varied across all studies, influenced by project characteristics, such as the number of projects studied and quantity and quality of project information. This study examines previous ROI studies on the implementation of SUE and compares the methodologies and cost-saving models used to account for the benefits of performing SUE on diverse construction projects. The study further investigates the results of the various cost-saving items and benefit factors to identify the most significant and least cost-saving items. The reduction in utility relocations during construction was identified as the significant cost saving in using SUE, while the direct cost to the public was identified as the least cost saving and not adequately estimated by most studies. The study supports why the adoption of SUE is encouraged for projects involving infrastructure construction and should be considered an integral part of engineering risk management for construction projects.
... However, the accuracy of this as-built information is often questionable. In fact, existing records and visible feature surveys have often been found to be 15-30 % off the mark and, in some cases, considerably worse (Maree et al. 2021;Al-Bayati and Panzer, 2020;Metje et al., 2015;Jeong et al., 2004). Thus, excavation contractors should use other methods, such as private locating firms and SUE providers, to check and validate marks provided through the one-call system (Al-Bayati, 2021). ...
... Thus, SUE is seeing increased use and becoming a standard process during the early stages of construction projects (Hutchins and Sinha, 2009). Although this service was initially used for mainly state and federal projects, the current customers for SUE are also engineering firms, municipalities, utility companies, and construction companies (Jeong et al., 2004). While designating utilities may require the use of surface geophysical techniques such as electromagnetic technology (mainly used by one-call locators) and ground penetrating radar (GPR), the utilization of these techniques is not to achieve SUE. ...
... Projects usually entail a mixture of utility quality levels (QLs) based on the information obtained, the information needed, and the manner of integrating methods of the geophysical, record, and site-visible features investigations. It is important to note that both the precision and reliability of underground information increases from QLD to QLA because superior technologies and processes are involved (Jeong et al., 2004). The costs for obtaining utility data also usually increase from QLD to QLA (Anspach and Scott, 2019). ...
Article
Full-text available
The ability to locate underground utilities is imperative for the protection of these facilities and for the coordination of these facilities with transportation projects. The proliferation of underground facilities in the United States has led to an increase in dig-in strikes resulting in loss of services, project delivery delays, injuries, and even deaths. In fact, the Federal Highway Administration found utility-related issues to be one of the top causes of delays for transportation projects. These delays are often attributed to unknown or inaccurate utility location information. This scenario has led to a vast industry of utility location service providers. Additionally, national and state damage prevention laws led to the creation of one-call systems for the purpose of providing a communication conduit between designers or constructors and utility owners and operators. The importance of accurate utility locates and the risk and liability of providing utility location services also led to the American Society of Civil Engineers (ASCE) standardizing the practice of Subsurface Utility Engineering (SUE) into a professional service. Even with this standard, there remains misinformation and misunderstandings regarding SUE and non-SUE services provided by private utility location firms. The differences between the services provided by SUE investigations and non-SUE private locating services that do not meet SUE standards has largely been anecdotal. This study serves as an advancement in understanding the distinction of SUE services versus non-SUE services and provides evidence of industry misunderstanding of differences in these service types.
... • The industry is still not familiar with the SUE standard. According to Jeong et al. (2004), the limited education about SUE is one of the greatest obstacles to utilizing it. The lack of education leads to many clients confusing the concept of SUE with the one call system and failing to use SUE private locating services. ...
... However, the owners should be aware of the added costs associated with design firms hiring a private locating firm. According to Jeong et al. (2004), more than ten times the funds invested in investigating underground utilities will be returned to the project owners in terms of fewer utility conflicts and relocations. There are four potential contributing cost saving categories from acquiring reliable information pertaining to the locations of underground utilities: ...
... Although expensive, burying utility networks is a global trend (Navigant Consulting, 2005). The reduction of visual intrusions and space savings associated with hiding utilities are widely considered to be aesthetic, efficient and ecologically friendly (Jeong et al., 2004). As a result, power and telecommunication networks are joining gas and water pipelines in an already dense underground. ...
... As discussed in Karki and Thomson (2014), fundamental examination should be done on this aspect, and collaboration among GIS specialists, lawyers/notaries and other specialists would be important to accomplish this. For example, a growing industry segment, subsurface utility engineering (SUA), focuses on the establishment of good practice guidelines to reduce uncertainty associated to construction projects (Jeong et al., 2004). As a first step in this direction, ASCE (American Society of Civil Engineering) has published a guideline for the collection and depiction of existing subsurface utility data (ASCE, 2002). ...
Conference Paper
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Placing utility networks underground is now a common practice in many countries. While technical challenges exist, administrative and legal issues also pose problems since the presence of underground networks creates restrictions and obligations for surface owners. Based on a case study in the province of Quebec, Canada, land registers are examined and jurisprudence reviewed, in order to create a clear portrait of current practices regarding the registration and publication of real rights attached to underground utility networks. Consequently, five challenges were identified and a discussion is proposed to help official land administration authorities and stakeholders take better decisions regarding creating a full 3D Cadastre or not. see paper at http://www.fig.net/resources/proceedings/fig_proceedings/fig2016/papers/ts02c/TS02C_pouliot_girard_8086.pdf ISBN 978-87-92853-52-3
... The insufficiencies of as-built drawings are expected to be solved according to Pettee (2005), via educating the different parties to follow the standards for preparing the drawings and incorporating GSM & GPS. The Subsurface Utility Engineering (SUE) is also used to verify the underground services (Jeong et al., 2004). Moreover using3D laser scanning and photogrammetry (Klein et al., 2012), BIM models (Giel & Issa, 2011) and the intranet system can give sufficient accuracy. ...
... According to Hegazy & Abdel-Menem (2012) using slow information system for producing as-built drawings caused project delay and overrun cost in addition to affect efficiency of operation and maintenance processes ).The inaccuracy of presenting the concealed MEP services has a serious impact on the construction industry in USA after War II as well as accidents leading to contractual disputes for clients (Jeong et al., 2004). This problem caused wasting $4.8 billion for verifying the existing as-built drawings ( Klein et al., 2012). ...
Conference Paper
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As-built drawings represent the final constructed projects. They are the contract drawings revised during construction and before handing over including all changes. They provide owners & facility managers with a proper reflection of a facility by which the necessary information are used for operation & maintenance processes. They are successfully used in developed industries in the world. This paper is mainly aimed to investigate the significance of buildings’ as-built drawings in Dubai through examining the factors that determine their value in terms of availability, accuracy, impact on cost, time & safety. This work will study the significance of mismatches between final drawings and the as-built projects in villas, multi-story and industrial buildings. Technical reports of more than 170 projects were studied in order to analyse and assess the mismatches found at the final inspection for the completion certificate process. The results show 53% of buildings studied had mismatches mainly in external elevations, internal design features and fixtures, specifications, and general works omissions. Improving as-built drawings can be achieved by handling such mismatches earlier in projects’ brief and design.
... This crucial problem will worsen as cities expand and their networks increase in size and complexity [2] [3]. Urban works will thus be more prone to delays with concomitant additional costs [9] [10]. However, some of these networks have surface access traps which may be visible on airborne or satellite images. ...
... The results are compared in terms of precision and recall: precision = TP TP+FP (9) recall = TP TP+FN (10) with TP: true positive (number of correctly detected manhole covers); FN: false negative (number of omitted manhole covers); FP: false positive (number of objects confused as manhole covers). ...
Conference Paper
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The detection of small objects from aerial images is a difficult signal processing task. To localise small objects in an image, low-complexity geometry-based approaches can be used, but their efficiency is often low. Another option is to use appearance-based approaches that give better results but require a costly learning step. In this paper, we treat the specific case of manhole covers. Currently many manholes are not listed or are badly positioned on maps. We implement two conventional previously published methods to detect manhole covers in images. The first one searches for circular patterns in the image while the second uses machine learning to build a model of manhole covers. The results show non optimal performances for each method. The two approaches are combined to overcome this limit, thus increasing the overall performance by about forty percent.
... Important goals for this " dual-array " system were the capabilities to operate in most soil conditions, to cover large areas efficiently, and to map both plastic and metal utility lines, including large conduits at depths of 10 m or more (Witten Technologies Inc., 2005). The specifications were based on applications such as subsurface utility engineering (SUE) (Anspach, 1995), which require a resolution and accuracy on the order of centimeters in mapping utility networks that can extend over kilometers (Jeong et al., 2004). Meeting these specifications would represent a dramatic increase over previous capabilities in geophysical mapping of infrastructure and has become possible recently with the availability of rugged, affordable EM sensors, along with faster and more accurate data acquisition electronics and position measurement systems. ...
... Important goals for this "dual-array" system were the capabilities to operate in most soil conditions, to cover large areas efficiently, and to map both plastic and metal utility lines, including large conduits at depths of 10 m or more (Witten Technologies Inc., 2005). The specifications were based on applications such as subsurface utility engineering (SUE) (Anspach, 1995), which require a resolution and accuracy on the order of centimeters in mapping utility networks that can extend over kilometers ( Jeong et al., 2004). Meeting these specifications would represent a dramatic increase over previous capabilities in geophysical mapping of infrastructure and has become possible recently with the availability of rugged, affordable EM sensors, along with faster and more accurate data acquisition electronics and position measurement systems. ...
Conference Paper
Complementary data from a Ground-Penetrating imaging Radar (GPiR) array and a prototype broadband vector electromagnetic (EM) induction array are used to efficiently map subsurface utilities on a large-scale. Both trailer-based arrays are monitored by an accurate robotic laser positioning system while moving in arbitrary patterns over the survey area. The data from side-by-side passes of each 2 m wide array are merged to create continuous and seamless coverage. Processing, interpretation and visualization software using advanced signal and image processing algorithms complement each array. The EM array data are analyzed with forward and inverse numerical modeling. The GP/R array yields high-resolution three-dimensional radar images of the shallow subsurface. The array of broadband (1 kHz to 80 kHz) vector electromagnetic induction sensors collects time series' that produce detailed maps of three orthogonal electromagnetic field polarizations. The receiver array operates with multiple "clamp-on" sources directly coupled to a particular pipeline and/or with an "onboard" source moving along with the array at a fixed spacing. All transmitters are broadcasting simultaneously and continuously each at a different frequency. Typically radar traces are collected on a 10 cm and EM data on a 30 cm grid. Both array systems are briefly described before discussing how their data sets complement each other to create better subsurface utility maps. Finally we examine the complementary nature of both technologies through an example dual array survey conducted near Elmsford, NY for Consolidated Edison Company of the New York.
... The Federal Highway Administration is encouraging state DOT's to use SUE. Based on a survey conducted in 2002, 22 state DOT's are using SUE with an average annual budget of approximately US$2M (Hyung et al 2004). The technology has been recently introduced to Ontario with plans for expansion to other provinces. ...
... SUE is now being provided by specialized service providers as well as civil engineering firms. In 1989, a court of competent jurisdiction recognized that SUE services are professional services rather than contractor services (Hyung et al 2004). ...
Article
Full-text available
Subsurface Utility Engineering (SUE) has emerged as a process researching, locating and delivering location-based information for buried utilities. SUE utilizes techniques from civil engineering, surveying, geophysics and nondestructive excavation for the accurate location of underground infrastructure. This paper presents the preliminary results of a study undertaken by the University of Toronto to gauge the effectiveness of using SUE on large infrastructure projects in Ontario. Average costs savings were estimated based on 5 projects analyzed to-date. This paper presents details of these case studies and highlights how SUE was beneficial to the overall project outcomes. These case studies show how the information provided by SUE revealed several inconsistencies between what is on record and what is actually underground. The paper sheds light onto current locating services provided in Ontario and outlines some of the most predominant processes for sharing infrastructure information among utility owners.
... For example, Sterling [14] surmised in his report that we need "techniques that accurately resolve the position and type of an underground utility in the presence of other underground utilities and structures." Jeong et al., [15] lamented about the drawbacks of current methods such as GPR with its "inapplicability to high conductive soils, clay and saturated soil, practical limitation of imaging objects located 2 m below the surface,…" On the other hand Jeong et al. also found in a survey that the most significant issue is "the unavailability of adequate information for existing underground utilities (that) causes problems in searching and finding surface appurtenances (starting point of utility tracing) and selecting appropriate equipment for tracing utilities" [15]. Different research groups are working on various aspects of the problem. ...
... For example, Sterling [14] surmised in his report that we need "techniques that accurately resolve the position and type of an underground utility in the presence of other underground utilities and structures." Jeong et al., [15] lamented about the drawbacks of current methods such as GPR with its "inapplicability to high conductive soils, clay and saturated soil, practical limitation of imaging objects located 2 m below the surface,…" On the other hand Jeong et al. also found in a survey that the most significant issue is "the unavailability of adequate information for existing underground utilities (that) causes problems in searching and finding surface appurtenances (starting point of utility tracing) and selecting appropriate equipment for tracing utilities" [15]. Different research groups are working on various aspects of the problem. ...
Article
Today's non-invasive technologies for locating buried utilities can be considered as ancient. However, Ground Penetrating Radar (GPR) has recently received significant attention from the scientific community since it showed great promise in detecting landmines. Yet, the complexities of the underground, especially in inhabited areas, makes “seeing-through-the-earth” to find buried utilities extremely difficult. This paper presents the results of a data processing method, called Translation Invariant Wavelet Packet Detection (TIWPD), applied to filtering GPR data collected on a university campus. It first provides a brief introduction into the working principles of scanning the ground with electromagnetic radar waves that are being refracted, scattered, and reflected by buried objects of all sizes and materials. In its main section, the paper presents the results of experimental deployment of the system during a construction project that involved the extensive excavation trenches to lay chilled water pipes. The significance of this paper lies in its use of real-world GPR data to demonstrate the performance characteristics of the filtering process and its validation with the actual condition found during excavation. The encouraging results of this work should provide the basis for developing a near-real time utility detection system that can be used by laborers in the field.
... • Attempt to achieve QLB on all utilities within the proposed excavation area unless a reasonable rationale is provided by the engineer, and • Attempt to achieve QLA for underground facilities at the point of a potential conflict with the installation of a gravity-fed system. The limited education about SUE is one of the most significant obstacles to its utilization (Jeong et al., 2004). It leads to many owners confusing the concept of SUE with services provided by One Call systems or private locating firms while missing the benefits of SUE during the design phase. ...
Conference Paper
Full-text available
The American Society of Civil Engineers (ASCE) defines utility engineering as a branch of civil engineering that focuses on the plan, position, design, construction, operation, and maintenance of utilities. Additionally, in 2002, ASCE published the first national standard for subsurface utility engineering (SUE) (i.e., ASCE 38). The second version of the ASCE 38 was published in 2022. One of the objectives of ASCE 38 is reducing the number of damages to underground utilities. The number of damages to subsurface infrastructure is a concerning issue in modern cities where essential daily services such as potable water, natural gas, and electricity are delivered through a dense network of underground utilities. This study explores the current understanding and utilization of ASCE 38 in the United States. Accordingly, an online stratified random sample survey was designed to collect relevant information from practitioners in the state of North Carolina. Among other findings, the lack of awareness of the SUE standard and its guidelines is of significant concern. Accordingly, an effort is needed to raise awareness and investment in SUE. Thus, the study results are anticipated to contribute to better utilization of ASCE 38, which helps improve damage prevention efforts in the United States.
... however, the results will still be helpful and relevant. Also, the same methodology was adapted from many studies before [42,43]. The results from the cost-benefit analysis will be discussed in the following sections. ...
Conference Paper
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Nowadays, it is crucial to have sustainability; water sustainability is one of the sustainable development goals. However, many threats face water sustainability. One of the challenges towards reaching water sustainability is represented in the high levels of non-revenue water (NRW) that faces many countries. As a step towards reducing NRW and reaching water sustainability, this paper aims to identify the cost-effective water distribution network (WDN) rehabilitation approaches. First, WDN rehabilitation approaches were identified from a systematic review. Then, the identified WDN rehabilitation approaches were used in the development of the questionnaire survey. 176 valid responses were collected, the collected data was analyzed using mean score ranking, normalization, and cost-benefit analysis. The results of the data analysis showed that the cost-effective approaches are; Pipe bursting, Compact pipe, Pipe ramming, Trenchless, Supervisory control and data acquisition (SCADA), cured-in-place pipe (CIPP), Zoning network, and Slip lining. The findings can be a valuable reference for the water industry in the WDN rehabilitation process. Further analysis and development are required to get rid of each approach’s limitations. Reducing NRW is regarded as a top solution towards having water sustainability suitable development.
... Quality levels in subsurface utility engineering.(Jeong et al., 2004) ...
... The digitization of 3D building data has been a rapidly developing approach to 'as-built' information management. An as-built building information modeling process has two major stages: data acquisition and processing, and data modeling (Jeong et al. 2004;Pătrăucean et al. 2015). The introduction of LST represented a major change in terms of data acquisition. ...
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The generation and use of 3D images and visualizations through remote sensing, Building Information Modeling, and Augmented Reality technologies, have come to play a significant role in construction engineering practice. Although these technologies are promising, their potential can be misjudged when potential end-users are unaware of key assumptions that were made by developers. Realistic expectations require insights into the ways in which these technologies transform input collected into 3D visualizations and how these visualizations are possibly used on construction sites. This study’s objective is hence to explore the form of technological mediation that the generation and use of 3D images and visualizations provide between a human and objects, or aspects of these objects, that would otherwise be largely imperceptible to professionals in construction practice. We show that algorithms pre- and post-process data through their technological selectivities, which function as mediators. Double mediations of augmented and engaged relationships play a dominant role in the use of 3D images and visualizations and enhance the situational awareness of professionals in construction practice. This is the first study that applies this perspective to increase the understanding of the mediating role of 3D images and visualizations in construction practice.
... A utility surveyor is either contracted, or operators are provided with the necessary training and tools to detect buried assets. It should be noted however that a geophysical survey, including a CAT & Genny, should be a specialist job, and not left to operatives on site (Jeong et al., 2004;Zembillas & Beyer, 2004;Ellis & Lee, 2005;Zembillas, 2008;Sterling et al., 2009;Thelin et al., 2011). As part of utilities programme management, an 'active service detection' activity schedule is produced, with appropriate resources and time. ...
Technical Report
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The aim of this report is to assess the impact of utility strikes and their associated true costs by detailing 16 case studies of utility strikes and providing an objective view of all their quantified associated costs, both those paid directly by contractors (direct costs), and those borne by third parties in the contractual agreement (indirect costs), and other parties not engaged in the contractual agreement (social costs). This report details the results from the quantification of these 16 case studies, reviews literature on the subject of utility strikes and puts forward a robust methodology that can be used to estimate the true cost of utility strikes. It identifies the ways in which these costs can be minimised as well as gaps in knowledge requiring further research. Based on the findings presented in this report, it is clear that if the true costs of utility strikes are to be reliably understood and quantified throughout industry, then more work in this area will be required by industry bodies to provide joined up thinking and formulate a robust industry baseline measure for utility strike impacts beyond the status quo. This in turn will aid the development of a better understanding of what street works, moreover, utility strikes cost both the utility industry as a whole and society in general. Furthermore, in order for the findings of this report to have a practical commercial benefit, it is necessary to understand that more exploratory work and therefore upfront spending will be required on projects to reduce the risk of utility strikes. This approach when employed should demonstrate to all concerned in projects, that up front feasibility, surveys and design work is money well spent as it reduces the costs associated with utility strikes.
... In highly populated areas, a complex mesh of vital utilities such as gas pipelines, power and communication cables, drinking water, and wastewater systems, is buried underground, beyond sight ( Figure 1). With the population growth and urban development, it is challenging not only to maintain an up-todate spatial database of existing underground utility networks (UUN) but also to acquire spatial data of buried infrastructures in non-invasive ways (Jeong et al., 2004;Navigant Consulting, 2005;Pouliot and Girard 2016). For any development project requiring excavation and trenching, it has become more and more essential to acknowledge the necessity of having an available and reliable current database of UUN in order to avoid interruption of services and downtime costs due to damage (Costello et al., 2007;Lew and Anspach, 2000;Metje et al., 2007). ...
Article
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For the planning and sustainable development of large cities, it is critical to accurately locate and map, in 3D, existing underground utility networks (UUN) such as pipelines, cables, ducts, and channels. An emerging non-invasive instrument for collecting underground data such as UUN is the ground-penetrating radar (GPR). Although its capabilities, handling GPR and extracting relevant information from its data are not trivial tasks. For instance, both GPR and its complimentary software stack provide very few capabilities to co-visualize GPR collected data and other sources of spatial data such as orthophotography, DEM or road maps. Furthermore, the GPR interface lacks functionalities for adding annotation, editing geometric objects or querying attributes. A new approach to support GPR survey is proposed in this paper. This approach is based on the integration of multiple sources of geospatial datasets and the use of a Web-GIS system and relevant functionalities adapted to interoperable GPR data acquisition. The Web-GIS is developed as an improved module in an existing platform called GVX. The GVX-GPR module provides an interactive visualization of multiple layers of structured spatial data, including GPR profiles. This module offers new features when compared to traditional GPR surveys such as geo-annotated points of interest for identifying spatial clues in the GPR profiles, integration of city contextual data, high definition drone and satellite pictures, as-built, and more. The paper explains the engineering approach used to design and develop the Web GIS and tests for this survey approach, mapping and recording UUN as part of 3D city model.
... Mispositioning of buried utilities is an increasingly important problem both in industrialized and developing countries because of urban sprawl and technological advances that create new needs among consumers resulting in additional cables and pipes that have to be added and connected [5] [6]. Urban works will thus be more prone to delays with concomitant additional costs [7] [8]. Locating past records can be a cumbersome and time consuming task. ...
Article
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Mispositioning of buried utilities is an increasingly important problem both in industrialized and developing countries because of urban sprawl and technological advances. However, some of these networks have surface access traps, which may be visible on high-resolution airborne or satellite images and could serve as presence indicators. We put forward a methodology to detect manhole covers and grates on very high-resolution aerial and satellite images. Two methods are tested: the first is based on a geometrical circular filter, whereas the second one uses machine learning to retrieve some patterns. The results are compared and combined to benefit from the two approaches.
... GPS measures the horizontal coordinates of a detected underground utility and converts the buried depth to a vertical position that references a vertical datum. With GPS, the 3D location of the detected utility is geo-registered to a spatial referencing system as a permanent record, which is a request of many utility owners (Jeong et al. 2004). Hence, GPS is an integral and supplementary component to GPR, forming a complete locating and measuring system for underground utilities. ...
Article
Ground penetrating radar (GPR) is capable of detecting, locating, and characterizing underground utilities in a non-destructive manner. However, processing raw GPR scans to estimate the buried depth and radius of underground utilities remains a challenge in practice, which can be attributed to two main constraints: (1) the necessity of the GPR scanning trajectory being perpendicular to the centerline of the utility to be scanned and (2) the requirement of knowing either the velocity of the GPR electromagnetic (EM) waves traveling through heterogeneous soils or the range of the utility's radius. This paper presents a novel method to overcome the two limitations by simultaneously estimating the radius and the buried depth of underground utilities based on GPR scans and auxiliary global positioning system (GPS) data. First, GPR scans are pre-processed to extract raw data points. Thereafter, a generic hyperbola equation is proposed to model GPR raw data, which incorporates the relative angles between buried utilities and GPR scanning trajectories. The very important point (VIP) algorithm then is developed to estimate the radius and depth utilizing auxiliary GPS data. The proposed new method was validated using GPR field scans obtained under various settings and was found to increase the accuracy of estimating the buried depth and radius under a general scanning condition (i.e., when both the EM wave velocity and the range of the radius are unknown and the GPR scanning trajectory is not perpendicular to the centerline of the buried utility). (C) 2014 American Society of Civil Engineers.
... GPR has been intensely employed in detecting and locating underground utilities (Jeong et al. 2004) due to its high resolution imagery capability, fast data acquisition and cost effectiveness for mapping large areas (Birken et al. 2002;Simi et al. 2010). In this framework, damage to infrastructure during digging operations continues to be one of the major problems affect-posed method in different host media conditions. ...
Article
Ground penetrating radar (GPR) is widely used in subsurface investigations for extracting the position and the route followed by the utility, an issue that gains more and more importance when considering the cost related to trench damage and disruptions. However, it has been noted that various targets of GPR surveys, especially linear and elongated targets, have polarization‐dependent scattering characteristics. This implies that the visibility of a subsurface scatterer in the acquired data depends on the used antenna configuration and its orientation with respect to the feature to be imaged. Furthermore, wave attributes could be modified by the surrounding soil anisotropy and heterogeneity degree. As the GPR antennas are composed of directional dipoles, any changes in the propagation plane of the returning wave affects the recording of GPR data. This work presents an approach based on a combination of mutually orthogonal GPR 3D data volumes through which polarization issues can be overcome, ensuring target detection even when the position and material are adverse. The strategy is evaluated through two field examples: in homogeneous soil this technique fully recovers the polarization mismatch, providing results that are closely similar to the ones that would be obtained with the optimal configuration; in heterogeneous environments it overcomes the wavelet alteration, depolarization included, strongly enhancing the signal to noise ratio and improving target reconstruction.
Chapter
This chapter reviews the remote sensing of buried utilities by mobile sensor arrays and describes uses of today’s commercial devices in mapping utilities during the design, engineering, construction, monitoring, and servicing of civil infrastructure. Our survey concentrates on techniques using electromagnetic (EM) waves to probe a few meters underground with sensors placed just above the ground, either to passively record the slowly varying magnetic fields emanating from buried power lines or to actively transmit and record EM induction (EMI) signals at kilohertz frequencies and ground-penetrating radar (GPR) at megahertz to gigahertz frequencies. These technologies have improved dramatically in the last 20 years by combining broadband sensors with modern positioning systems, sophisticated signal processing, and three-dimensional (3D) visualization. The main advances since publication of the first edition of this work in 2014 have come in hardware, with faster electronics now available to digitize radar signals at nearly gigahertz (GHz) frequencies in real time—thereby enabling a new generation of sensor arrays which can move with traffic. In addition, more accurate standards and improved geographic positioning systems are pushing subsurface utility engineering (SUE) into the realm of comprehensive 3D mapping which favors integrated sensor arrays. The capabilities of commercially available array systems are described; field examples from several different sites and applications are shown.
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Disputes are very common in the construction industry. Many claims, conflicts, and other issues result in disputes between project parties. This paper aims to propose integrated project delivery (IPD) as an innovative solution that can be implemented using building information modeling (BIM) to lessen disputes in any construction project. IPD is a project delivery method that can be used to conduct large-scale projects. It is a formal partnership that occurs starting early phases such as the design and continues throughout the planning, and execution phases of a project. In this paper, an extensive review of literature is conducted to discuss the main causes of disputes and how can they be categorized. It also compares the IPD contracts to traditional contracts and new relational project delivery agreements such as the project partnering and project alliance. The research also discusses IPD advantages and challenges. Finally, the research discusses how BIM can be a tool that facilitates IPD implementation while also discussing BIM advantages and how BIM can help overcome IPD challenges. Then, this paper studies the relation between dispute, IPD, and BIM; a table is conducted to explain each dispute cause, the IPD characteristic(s) that helps eliminate this cause, and the BIM tool/characteristic that will help implement BIM. Moreover, the paper presents two case studies where IPD were implemented and how this contributed into improving the project as a whole and eliminating disputes.
Conference Paper
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The construction industry influences economic developments in countries worldwide. Any construction project is associated with risks and challenges which lead to the project’s failure. Preventing the project failure is a priority in the construction business. On the other hand, in Egypt there are a lot of cases of failed construction projects. Most of these cases were a result of wrong decisions based on the lack of information. The term “Data-Driven Assets” describes a business state where data is used to support decision-making and other related activities efficiently in real�time. Data is more than just a tool to inform reports. Moreover, data-driven assets is a decision�making approach combining successful data storage, modelling, and availability. In addition, it can be used as a tool to create a framework for risk management that reduces the risk and prevents failure in construction projects during the design phase in Egypt. This research aims to investigate the role of risk management and data-driven assets as an approach to reduce construction projects failure during the design phase. This will be based on the investigation of the literature review, and the analysis of the case studies on projects that failed due to lack of information.
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Underground utility incidents, such as utility conflicts and utility strikes, result in time and cost overruns in construction projects, property damages, environmental pollution, personnel injuries, and fatalities. A main cause of recurrent utility incidents is the noncompliance with the spatial configurations between utilities and their surroundings. Utility specifications usually contain textual descriptions of the spatial configurations. However, detection of spatial defects, according to the textual descriptions, is difficult and time consuming. This deficiency is because of the lack of spatial cognition in many rule-checking systems to process massive amounts of data. This study aims to automate utility compliance checking by integrating natural language processing (NLP) and spatial reasoning. NLP algorithm translates the textual descriptions of spatial configurations into computer-processable spatial rules. Spatial reasoning executes the extracted spatial rules following a logical order in a geographical information system (GIS) to identify noncompliance. The intellectual contribution of this study is twofold. First, complex spatial rules are retrieved automatically from textual data with their hierarchies classified, which provides the inputs and indicates the sequence of rule execution in spatial reasoning. Second, semantic spatial relations are modeled on the basis of their metric and topological implications, enabling the automatic execution of multiple spatial rules. Experiments were conducted to test this framework. The average precision, recall, and combination of the two (F-measure) achieved by the NLP algorithm for extracting spatial rules are 87.88%, 79.09%, and 83.25%, respectively. In addition, the spatial reasoning mechanism also was found to be a powerful tool for compliance checking under various scenarios.
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Underground asset locating practices use new and existing technologies to accurately identify, characterize, and map buried utilities through the integration of professional utility records, visual site inspection, geophysical techniques, survey, and utility exposure. The efficient use of locating practices allows effective condition assessment and renewal engineering applications, which, in turn, improves asset management practices for water utilities. Utility engineers, managers, and practitioners need to be familiar with all locating technologies (working principles, capabilities, and limitations) to have an effective selection of the appropriate technologies for every scenario. There are capabilities and limitations of all existing underground utility locating technologies that are used by water utilities. This paper provides the factors affecting the reliability of underground pipe locating surveys and presents an overview of the capabilities and limitations of the locating technologies to guide water pipeline infrastructure practitioners through literature. Application of underground utility locating technologies by water and wastewater utilities was investigated through case studies and phone interviews. Recommendations on ways to improve locating technology applications for water and wastewater utilities were made based on the literature and practice review.
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A pilot project was commissioned by the Istanbul Metropolitan Municipality to assess the combined capabilities of traditional Subsurface Utility Engineering (SUE) and Ground Penetrating imaging Radar (GPiR) to accurately map and identify the utilities underneath the historic streets of Istanbul. The array based GPR technology combined with cm accuracy land surveying and advanced imaging software allows for an efficient and complete mapping of large-areas (1000's of square-meters) with radar traces collected on a 10 cm grid. The resulting high-resolution 3D radar images are interpreted for utility lines, which are then identified and calibrated with standard SUE techniques. The combination of SUE and GPiR is a powerful technology that produces more accurate utility maps than by each method alone. The complementary technologies were successfully applied in the Eyup district of Istanbul. Typically we achieved good radar penetration down to a depth of approximately 1.5 m, after that a clay layer attenuates the radar signal significantly. The Municipality received accurate CAD drawings with the 3D location of each pipe as determined by GPiR and SUE.
Chapter
This chapter reviews the remote sensing of buried utilities and explores its uses in today's commercial devices and in research systems that may become commercially available in the next ten years. Our survey concentrates on techniques that use electromagnetic (EM) waves to probe a few meters underground. These technologies have advanced dramatically during the last decade by combining broadband sensors with modern positioning systems and sophisticated signal processing. Sensors moving just above the ground, while transmitting and recording induction signals at kilohertz frequencies or ground-penetrating radar (GPR) at megahertz to gigahertz frequencies, have so far been easiest to deploy and interpret.
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Underground utility lines being struck is a long-standing problem worldwide, causing public service disruptions, project delays, cost overruns, property damage, injuries, and fatalities that cost billions of dollars each year. Utility strikes are attributed to two main causes: the lack of reliable data regarding the true locations of underground utilities and the lack of an effective means to communicate the inherent uncertainties associated with utility location data to end-users (e.g., excavator operators). Inaccurate utility location information leads to falsely instilled confidence and potentially misleads equipment operators into unintentional utility strikes. There is a great need to map underground utilities and to model and communicate uncertainties to end-users for safe excavations. This paper presents a geospatial system for mapping and uncertainty-aware visualization of underground utilities. Ground penetrating radar (GPR), global positioning system (GPS), and geographical information system (GIS) are integrated into a total 3G system for geospatial utility data collection. Field experiments are conducted to assess the locating accuracy of the system and reveal the patterns of positional errors. Three-dimensional (3D) probabilistic uncertainty bands that enclose the true utility line with specific probabilities are developed to handle the positional uncertainties of underground utilities. Multipatch surface models are adopted to visualize the 3D uncertainty bands in GIS to communicate both the locations of utilities and the associated uncertainties to end-users. The geospatial 3G system, together with the proposed 3D probabilistic uncertainty bands, enables the mapping and visualization of some underground utilities in a non-destructive and uncertainty-aware manner to avoid disastrous utility strikes and promote safe excavations.
Conference Paper
A project sponsored by the United States Department of Transportation (U.S. DOT) has developed a new mobile geophysical system combining an array of broadband electromagnetic induction (EMI) sensors with an array of ultra-wideband ground-penetrating radar (GPR) antennas. This "dual-array system" was designed for mapping underground utility networks efficiently over large areas, but can also be useful in environmental surveying for applications such as leak detection and hazardous waste monitoring. The project was part of the Pipeline Safety Research and Development Program1 of the U.S. DOT Research and Special Programs Administration. Several utility companies, including Consolidated Edison Company of New York and Regional Water Authority of South Central Connecticut, participated in the project. The EMI array consists of 16 vector magnetometers (induction coils) with a flat frequency response from about 1 to 100 kHz. Signals from each sensor are recorded and digitized as time series, with a sampling rate of 1 MHz. The EMI sensors are arranged in two linear arrays, each consisting of 8 sensors with a spacing of 30 cm; the arrays are offset vertically by about 50 cm. The system works with two types of transmitters: "clamp-on" transmitters which can inject current at discrete frequencies onto individual pipes (by galvanic or toroidal clamps) and a 3-axis induction coil which rides "on-board" with the transmitters and operates over the same frequency range as the sensors. The GPR array, which is based on the commercial CART Imaging System (Birken et al., 2002), consists of 17 antenna elements in an arrangement that creates 16 independent radar channels (transmitter-receiver pairs). The GPR array system has two antenna sets: one set has a central frequency of about 200 MHz and a channel spacing of about 14 cm; the other, a central frequency of 400 MHz and a spacing of 8 cm. The positioning system is designed to allow surveying in arbitrary patterns. Each array is mounted on a trailer whose position is monitored by a laser surveying instrument as the array moves over the survey area. Special algorithms merge data from different passes of each array to create a regular data grid. The radar data are imaged into a 3D volume using standard synthetic-aperture seismic imaging techniques adapted for GPR. The EMI data are inverted using a parametric model that assumes currents in the subsurface flow mainly along a network of (possibly interconnected) pipes. Two large surveys have been conducted with the dual-array system. One survey in the spring of 2004 successfully mapped a complex network of subsurface water, electrical, gas and telecommunication lines in Connecticut for a local water utility company. This survey covered over 2000 sq m with radar traces on a 10 cm grid and EMI data on a 30 cm grid. A second survey done in the summer of 2004 mapped electrical lines emerging from an electrical substation in New York.
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A project sponsored by the United States Department of Transportation (U.S. DOT) has developed a new mobile geophysical system combining an array of broadband electromagnetic induction (EMI) sensors with an array of ultra‐wideband ground‐penetrating radar (GPR) antennas. This “dual‐array system” was designed for mapping utility networks efficiently over large areas, but can also be useful in environmental surveying. The project was part of the Pipeline Safety Research and Development Program of the U.S. DOT Research and Special Programs Administration. Several utility companies, including Consolidated Edison Company of New York and Regional Water Authority of South Central Connecticut, participated in the project. The EMI array consists of 16 vector magnetometers (induction coils) with a flat frequency response from 1 to 100 kHz, arranged in two linear arrays of 8 sensors each with a spacing of 30 cm; the arrays are offset vertically by about 50 cm. The system works with either “clamp‐on” transmitters which inject current at discrete frequencies onto individual pipes (by galvanic or toroidal clamps) and a 3‐axis induction coil which rides “on‐board” with the transmitters and operates over the same frequency range as the sensors. The GPR array (Birken et al., 2002) consists of 17 antenna elements in an arrangement that creates 16 independent radar channels (transmitter‐receiver pairs). Two large surveys were conducted with the dual‐array system in 2004. One survey successfully mapped a complex network of subsurface water, electrical, gas and telecommunication lines in Connecticut for a local water utility company. This survey covered over 2000 sq m with radar traces on a 10 cm grid and EMI data on a 30 cm grid. A second survey mapped a dense grid of electrical lines emerging from an electrical substation in New York.
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Accurate location of buried utility infrastructures is a vital issue for utility owners, utility managers and engineers, designers, and contractors that perform new installations, repairs, and maintenance on highway projects. Unreliable information on underground utilities can result in undesirable consequences such as property damage, claims, and other social and environmental problems. Subsurface utility engineering (SUE) is becoming a significant method for reducing the potential for underground utility conflicts at the project planning phase. SUE accurately identifies, characterizes, and maps underground utilities through four quality levels. This study presents a SUE benefit–cost analysis (BCA) to encourage a better understanding of SUE and the use of SUE. Eleven main benefit factors and two cost factors are identified and estimated on twenty-two SUE projects and eight non-SUE projects from Pennsylvania Department of Transportation (PennDOT) districts. In addition, this study reveals the relationship between benefit–cost ratio and complexity levels of buried utilities.
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Utility conflicts are unfortunately a common occurrence on many construction roadway projects. Through a combination of case studies and statistical analyses of variance, this paper examines the cost, frequency, and severity of utility conflicts by both type and location (urban versus rural roadway projects). Understanding the true costs of utility conflicts sheds light on the significant magnitude of added construction costs that utility conflicts impose on state transportation agencies, utility companies, contractors, and the public during roadway construction. Understanding when and what type of utility conflicts most likely occur will help state transportation agencies better understand the risk of utility conflicts on future projects. The analyses presented in this paper are a result of a survey completed by state utility directors from 45 different United States state transportation agencies as well as four in-depth case studies of Kentucky roadway projects that experienced utility conflicts during construction. In addition to examining the frequency and severity of different utility conflicts, the paper also examines practices being utilized by different state transportation agencies and their impact on the frequency and severity of the conflicts.
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A lack of reliable information regarding the locations of underground utilities can not only result in property damage, construction delays, design changes, claims, injuries, and even deaths but can also cause traffic delays, local business disruptions, environmental problems, and utility service breakdowns in highway projects. The subsurface utility engineering (SUE) is an engineering process designed to reduce the potential of underground utility conflicts at the planning phase. The SUE uses new and existing technologies to identify, characterize, and map accurately the underground utilities with three major activities: designation, location, and data management. In this study, a decision-support tool called the SUE utility impact rating form, which refers to utility complexity at the construction site, has been developed to determine which projects should include SUE and the appropriate levels of SUE investigation to be used. In addition, case studies with benefit–cost ratio have been performed to verify the form.
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This paper presents the framework for computing the optimal premium for workers' compensation insurance, and a fuzzy system conceptual model that automates the proposed framework. The fuzzy system model is able to compute premiums by linguistic assessment of project hazard levels, the contractor's crisis preparedness level, the insurer's profile and market conditions. The framework, together with the fuzzy approach, offsets the shortcomings of existing experience modification ratings for construction workers' compensation insurance premium computation.
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This paper investigates a relatively new engineering service that is being introduced in Ontario: subsurface utility engineering ( SUE). This service combines civil engineering, surveying, geophysics, and nondestructive excavation for the accurate mapping of underground utilities. This paper presents the results of a one-year study that investigated the use of SUE on large infrastructure projects in Ontario. The study involved performing a detailed cost analysis of nine successful SUE projects, four of which are presented in this paper. Potential cost savings were estimated for each case study and all indicated that SUE has a positive return on investment. In addition, two industry-wide surveys were conducted to investigate the effects of inaccurate utility information on projects. Results indicate that inaccurate utility information has a significant impact on project cost, schedule, and damage to existing utilities. Using the results of the case study analysis and the survey, a generic cost model for SUE was developed that relates project specific characteristics to costs that could be incurred because of inaccurate utility information. This investigation provides valuable insight to the application of a relatively new process in Canada following successful results in the United States.
Conference Paper
A lack of reliable information on the location of underground utilities can result in costly conflicts, damages, delays, service disruptions, redesigns, claims, and even injuries and lost lives during construction activities. While the location of subsurface utilities might be found on plans and records, experience has often shown that the utility locations are not exactly as recorded or the records do not fully account for the buried utility systems. This may be especially true of our nation's aged roadway infrastructure. An engineering process known as Subsurface Utility Engineering (SUE) has proven to be a welcome solution to providing this much-needed utility information. Combining civil engineering, surveying, geophysics, nondestructive excavation, and other technologies, SUE provides accurate mapping of existing underground utilities in three dimensions during the early design phase, which avoids unnecessary utility relocations and related downtime, eliminates unexpected conflicts with utilities, and enhances safety during construction. The use of SUE services has become a routine requirement on highway and bridge design projects, and is strongly advocated by the Federal Highway Administration and many State Departments of Transportation.
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The accurate location of underground structures is a serious problem in construction. Subsurface Utility Engineering (SUE) is an emerging solution to this subsurface structures problem. SUE is a process that incorporates new and existing technologies to accurately locate underground facilities during early development of a project. This paper discusses the current locating practices and the benefits that can be obtained through the application of SUE. It will be evident that SUE can reduce unexpected utility conflicts, construction delays, contractor claims, utility relocations, project redesigns, and the time required to design projects. In summary, when the SUE process is applied, contractors' risk is reduced, and a cost savings of 77-10, or possibly 15,forevery15, for every 1 spent on SUE is realized.
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