矿区地下管线探测及数据库建设方案

地下管线是矿山基础设施的重要组成部分,采用先进方法对矿区管线进行探测,查明管线现状,获取管线的属性信息和空间信息,利用GIS技术建立管线信息管理系统对矿区管线动态管理具有重要意义。针对矿区地下管线的分布特点,从探测前期准备、探测精度要求、工程质量检查和内业数据处理等方面对矿区地下管线的探测方法进行汇总,从管线数据标准化、管线系统数据库设计及管线信息系统组成等方面探讨利用GIS技术进行矿区地下管线数据库建设和系统开发的思路。     

Evaluation of Differing Subsurface Ground Conditions in Construction Contracts

Subsurface ground conditions present a big factor of uncertainty in a construction project. It is difficult to determine subsurface ground conditions even with a prebid site investigation. Nevertheless, such conditions must be included in the bid price. Due to this uncertainty, claims arise during the construction of a project. Many claims end up in litigation. This paper presents an analysis of legal cases dealing with differing subsurface ground conditions in construction contracts. By creating a database containing salient features from legal cases related to subsurface ground conditions, this research identifies the most important factors influencing the outcome of legal cases pertaining to subsurface ground conditions. Further, the most commonly used arguments by the litigating parties and the precedent cases supporting them are identified and categorized.     

Resistivity Survey of the Subsurface Conditions in the Estuary of the Rio de la Plata

An electrical resistivity survey was performed at the estuary of the Rio de la Plata, as part of more comprehensive geotechnical investigations of the subsurface conditions. The studies were required for the emplacement of a 3.5-m-diameter conduit proposed for the discharge of the treated wastewater of the city of Buenos Aires. The soil profile at the site consists mainly of clays and silts underlain by a layer of dense sand. The dense sand layer is a confined aquifer, and the project required that the depth to the sand layer be perfectly determined. Previous geophysical surveys at the site and the general geotechnical conditions showed the inadequacy of seismic methods, which are usually adopted in similar environments. The resistivity method was determined to be a reliable alternative, even though there has been little experience in surveying shallow depth water for geotechnical investigations. The four-electrode Schlumberger electrode array was adopted for the resistivity survey. Some of the test devices were developed especially for the purpose of this project. Calibration of the method was achieved with data obtained from boreholes. The results show that the resistivity technique performed satisfactorily to the 40?m depth required in this project. As a result of the survey, the next geotechnical investigation was focused on a more reduced area and the required number of boreholes was reduced substantially.     

Experience from Two Resistivity Inversion Techniques Applied in Three Cases of Geotechnical Site Investigation

The combination of in situ geotechnical testing and continuously measured geophysical data can be a powerful tool in geotechnical site investigation. In two cases from Sweden and one case from Denmark electric resistivity surveys are used successfully in geotechnical site investigations. The main contribution of resistivity results is the possibility to interpret continuous geological models. An improved methodology combines two-dimensional (2D) smooth inversion and 2D laterally constrained inversion (2D-LCI) to significantly increase interpretability. The 2D smooth inversion has high horizontal resolution and 2D-LCI high vertical resolution. The possibility to add a priori information from, for example, drill log data to constrain the 2D-LCI increases the confidence in the inverted model and limits ambiguity. In a site investigation for a railway trench in southern Sweden a geotechnical data set is used as a priori data to increase the reliability of the inversion of the resistivity data. From this combined survey a complex Quaternary geology is described in detail. A slope stability study from south of Stockholm, Sweden, employed resistivity data together with refraction seismic and geotechnical drill log data. The result gives necessary geometrical information for the important geological units, for example for stability calculations. Both these surveys were performed with a multielectrode system. In the third case a pulled array resistivity survey was used to map the uppermost 15–20?m to estimate the distribution of the geological formations for freeway construction in Denmark. The result enables a more accurate estimate of the total freeway construction costs.     

Risk-Based Safety Impact Assessment Methodology for Underground Construction Projects in Korea

Safety of construction projects may be affected by various factors such as types and scale of projects, construction methods, safety management procedure, climate, site conditions, etc. Among them is the quality of design in relation to safety. Presently, however, designers typically are not involved in construction safety. They are often uncertain of their responsibilities in relation to construction safety and fail to be responsible for avoiding or reducing safety-related risks. In this study, the concept of safety impact assessment to achieve “design-for-safety” in the design phase is introduced. For this purpose, a safety impact assessment model was devised, and a methodology using the risk-based safety impact assessment approach for open-cut type underground construction projects in Korea is suggested. The suggested methodology includes a safety information survey, classification of safety impact factors caused by design and construction, and quantitative estimation of magnitude and frequency of safety impact factors. A checklist which can be easily used for assessing the safety performance of design products is also proposed. A real-world case study on the safety impact assessment of a subway construction project in Korea is also provided in the paper.     

Performance of Active and Passive Methods for Measuring Low-Frequency Surface Wave Dispersion Curves

This paper examines the consistency between surface wave dispersion curves measured at wavelengths of up to 600 m using active and passive methods at sites in the Mississippi Embayment. Large-diameter (200 m) circular receiver arrays were deployed at five deep soil sites located in Tennessee, Arkansas, and Missouri to record ambient ground vibrations at low frequencies. Measurements were performed at the same locations using linear receiver arrays and actively generated low-frequency energy using the recently developed Network for Earthquake Engineering Simulation (NEES) field vibrator (termed Liquidator). Characteristics of the ambient wavefield measured at the five sites in the Mississippi Embayment are presented along with comparisons between the surface wave dispersion curves obtained from the active and passive measurements at each site. The ambient wavefield measurements exhibited peak levels in the frequency range of 1–5 Hz. Surface wave dispersion curves developed from frequency-wavenumber (f-k) processing of the active and passive methods were in good agreement at four of the sites, with phase velocities from the passive measurements within 5–10 % of the active-source measurements out to wavelengths of about 550 m. Improved comparisons were obtained at the fifth site by applying high-resolution f-k processing.     

黄金行业设备管理信息化建设的思考

简要介绍设备管理信息化建设的含义、意义和具体内容,着重分析目前黄金行业设备管理信息化建设的现状及存在问题;以黄金行业设备管理信息化建设的总体目标为指导,针对黄金行业设备管理的实际情况,提出了在信息化建设过程中的建议和措施。     

Economic Model to Optimize Underground Utility Protection

The need for better protecting our vital infrastructure from being damaged or destroyed has received increased attention since the terrorist attacks on September 11, 2001. The tragedy of having thousands of innocent people die before the eyes of an entire nation awakened people to the reality of “managed” attacks of unthinkable magnitudes. However, tragedies of a smaller scale are a daily occurrence but accepted as “collateral damage” of work in an unsafe environment. This paper presents a cost-benefit analysis to address the question of how much money should be spent in protecting underground utilities from damage. During the study of an actual incident it was found that the total costs of such accidents are vastly underreported because only costs for emergency responses and repair are tallied up. This paper makes the case that a comprehensive approach for assessing the total economic impact of such incidents on the public, business, and government is the critical stepping stone to a mathematical optimization of expenditure for damage prevention. In addition, the reader will quickly realize that the use of the presented optimization model provides theoretical underpinning for the engineering profession in its effort to better protect our critical infrastructure from terrorist attacks.     

Knowledge-Enabled Decision Support System for Routing Urban Utilities

This paper presents a Web-based system for supporting the selection of the most suitable routes for buried urban utilities. The aim of the proposed system is to support (not make) decisions through a collaborative semiautomated environment, in which stakeholders can share information and/or study the impacts of different routing alternatives with respect to decision constraints. First, the knowledge relating to route selection for urban utilities is represented through an ontology. The ontology defines the types and attributes of infrastructure products and the surrounding areas. It also defines the impacts of routing options on surrounding areas through a set of decision criteria adopted to evaluate the effectiveness of any route in terms of its potential impacts. A set of constraints are also defined to help represent/study the decision criteria. Second, a GIS-based system has been created to help visualize route data, interact with users, and support the needed discussions among stakeholders. The portal also achieves data interoperability through wrapping existing geospatial data with ontology structures. Finally, a set of reasoners have been created to help quantify/augment some of the constraints. The system is capable of (1)?extracting the attributes of each routing option, (2)?testing the interaction/conflicts between route attributes and the constraints of the surrounding area, (3)?studying the impacts of a route as stipulated in the ontology, (4)?referring users to existing best practices to help enhance routes or address conflicts and, when needed, (5)?develop objective measures for comparing different routes. On the microlevel (street level), route options are evaluated through a “constraint-satisfaction” approach. On the macrolevel (city level), route options are evaluated through a fuzzy inference scoring system. The proposed system focuses on facility life cycle, sustainability, and community impacts. Construction costing, scheduling, labor, and equipment along with other management issues can either be added to the system or, better, analyzed through integrating the system with four-dimensional (4D) modeling tools.     

浅析企业信息化建设

本文从企业信息化的概念出发,分析了我国企业信息化现状及存在的问题,最后提出了企业信息化建设的几点建议。     

Automatic As-Built Generation with Utility Trenchers

The proper functioning of the subsurface infrastructure is vital for the public, industry, and government. As is demonstrated almost daily, small disruptions or malfunctions of public utilities, such as power, gas, or phone, can result in catastrophic events on local, regional, or national levels. This paper addresses a known weak point in protecting buried utilities from damage, the lack of accurate as- builts. It is suggested to take advantage of enabling technologies to automatically create as-built drawings relying on electronic sensory data collected real-time from operating machinery. A significant portion of the paper discusses the development of a spatially integrated trencher, a prototype that was subsequently used to execute field experiments. The encouraging outcome of those tests, which are supported with actual data, demonstrated the soundness of the concept and the level of accuracy that can be expected. The relevance to the industry lies in that it addresses a real and complex problem, proposing and demonstrating a workable technology to close a large gap in the way we track our subsurface infrastructure. It is hoped that researchers will be encouraged to extend the concept to other relevant applications while applying a similar rigorous method of experimental field testing.     

Distributed Ontology Architecture for Knowledge Management in Highway Construction

The ongoing plethora of rehabilitation in the infrastructure domain requires more planning and integration during design and construction. To achieve this, there is a need for developing and using semantic (ontology-based) mechanisms for the exchange of development knowledge among all project stakeholders. This paper presents a distributed ontology architecture for knowledge management in highway construction. With every other utility tied to the highway geometry, the architecture is intended to be the base for a cross-discipline knowledge exchange in the infrastructure domain. The architecture presents highway knowledge on three levels: domain knowledge (an umbrella for infrastructure shared knowledge), application knowledge (representation of highway-specific knowledge), and user knowledge (an enterprise-specific representation of highway knowledge). The proposed architecture models highway concepts using six major root concepts: project, process, product, actor, resources, and technical topics (attributes and constraints). The architecture was developed using rigorous knowledge acquisition and ontology development techniques. It was developed as an extension for the e-COGNOS ontology. The architecture was validated through input from domain experts.     

Integration of Construction As-Built Data Via Laser Scanning with Geotechnical Monitoring of Urban Excavation

The demand for urban underground space has been increasing in the past decades to create living space and to avoid traffic congestion. A critical concern during the design and development of the underground space is the influence of construction-related ground movements on neighboring facilities and utilities. Currently, engineers can estimate ground movements using a combination of semiempirical methods and numerical model simulation. However, these advanced analyses require accurate as-built construction staging data, which most projects lack. The traditional approach of collecting construction-staging data is both labor intensive and time consuming. This paper explores the use of three-dimensional laser scanning technology to accurately capture construction activities during development of an urban excavation. The paper describes the planning, execution, and data processing phases of collecting accurate construction as-built staging information over a period of 4?months at an urban excavation site in Evanston, Ill. The resulting data provide an unprecedented level of detail on the as-built site conditions and provide much needed information to civil engineering disciplines involved in an urban excavation including construction management and structural and geotechnical engineering.     

物探技术在地质找矿中的应用探讨

随着科学技术的快速发展,物探技术日益应用到地质资源勘查中。本文首先综述了地质物探勘查的技术和思路,以地震方法为例,介绍了物探的一些具体方法,并综合物探在地质矿产勘查中的应用,最后提出了一些看法和建议,具有一定的理论价值和现实意义。     

Identification of Decision Drivers for the Strategy of Incorporating Utility Relocations into Highway Construction Contracts

The adjustment of utilities prior to highway construction is a particularly complex and challenging operation. One strategy that has been adopted in the last two decades is to incorporate utility adjustment work into highway construction contracts. In theory, this approach eliminates or reduces some of the complications and risks of utility adjustments. This paper aims to identify and analyze the decision drivers for selecting this strategy and help alleviate its implementation challenges. To this end, a comprehensive literature review and several interviews with experts from state departments of transportation and utility companies were conducted. Assessment surveys regarding the performance of recent projects that used the combined strategy were performed. Conclusions and recommendations for future research are presented.     

Legal Consequences of Damages to Underground Facilities by Horizontal Directional Drilling

Horizontal directional drilling is rapidly becoming the method of choice for installing new underground systems including water, sewer, electrical, telephone, fiber-optic cables, and gas lines. Due to its minimal impact to surface activities and competitive cost, this technique is being utilized worldwide. Unfortunately, poor drilling practices by some contractors have caused utility strikes that have resulted in major legal ramifications and subsequent negative image of the technique. Just one incident alone can result in significant monetary judgments due not only to the reparation for repairing the damaged utility, but also for damages due to “loss of use.” This paper presents theories of legal liability and recoverable damages applied to incidents of damages to underground facilities by the contractor. Recommendations for preventing the repetition of these types of incidents through the discussion of prior identification of potential hazards and proper drilling practices are discussed.     

Determination of Key Performance Indicators with Enterprise Resource Planning Systems in Engineering Construction Firms

The study focuses on developing a unified approach to define information specificities for key performance indicators (KPIs). Borrowing from the time-system theory, the paper defines different types of KPI and identifies that a KPI has two dimensions—knowledge specificity and time specificity. Different approaches are presented to analyze knowledge and time sensitivities. This paper addresses a key question related to enterprise resource planning (ERP) systems applications in the engineering construction industry: what are the areas of business processes within the engineering construction industry where ERP cannot be used to collect KPIs related to business processes? The writers review empirical and specialized processes within the construction industry to identify business processes not covered by existing ERP systems. A survey focused on qualitative aspects of ERP systems implementation in engineering construction firms was conducted among ERP-enablers in the construction industry and provided a basis for the presented case study. Data collected are from major engineering and construction firms in the United States and therefore the results are relevant for researchers and industry practitioners concerned with application of enterprise management systems in the respective firms.     

Case?Study: Application of GPR to Detection of Hidden Dangers to Underwater Hydraulic Structures

After long-term operation, a variety of hidden defects will occur in hydraulic structures, which will endanger the safety of a water conservancy project. In particular, hidden defects located below the water surface cannot be easily recognized by conventional methods and thus constitute the main reason for occurrence of dangerous situations in such hydraulic structures. It is therefore necessary to carry out periodic checks on the underwater structures. Ground-penetrating radar (GPR) is a high-resolution, nondestructive technology for detection of underground objects using a high-frequency electromagnetic pulse, and has been extensively applied to a variety of fields such as engineering/geologic exploration, underground archaeological survey, detection of scour holes around bridge piers, etc. In order to investigate the capability of GPR in detecting hidden dangers to underwater hydraulic structures, the authors have conducted GPR application-related experiments for more than 20 hydraulic projects since 1996, and in order for the GPR application to be successful in narrow spaces such as lock chambers, the authors also designed an antenna that can be directly operated on the water’s surface. Experimental results demonstrate that GPR can be used not only to detect hidden dangers with high precision, such as uneven settlement and cracking at impervious blanket or apron water bottoms, but also to detect hidden dangers to underwater hydraulic structures, such as damage of reverse filter below the sloping clay core of a dam, settlement and cracking of the antiseepage geomembrane at the bottom of a reservoir, concentrated seepage channel, etc. The application effect will be demonstrated in this paper based on some practical examples of using the GPR technique for such types of detection.     

浅谈信息资源管理和管理信息系统建设

科学管理现代化是实现四个现代化的基础。建立经济信息自动化管理系统是国民经济发展的需要。简略解释了信息资源管理和管理信息系统建设，浅谈了怎样建设管理信息系统，做好信息资源管理，并发挥人在现代化自动管理中的因素作用。