Weather-related geo-hazards are a major concern for both natural slopes and man-made slopes and embankments. Government agencies and private companies are increasingly required to ensure that there is adequate protect...Weather-related geo-hazards are a major concern for both natural slopes and man-made slopes and embankments. Government agencies and private companies are increasingly required to ensure that there is adequate protection of sloping sur- faces in order that interaction with the climate does not produce instability. Superior theoretical formulations and computer tools are now available to address engineering design issues related to the near ground surface soil-atmospheric interactions. An ex- ample is given in this paper that illustrates the consequences of not paying adequate attention to the hazards of slope stability prior to the construction of a highway in South America. On the other hand, examples are given from Hong Kong and China's Mainland where significant benefits are derived from putting in place a hazard slope stability management system. Some results from a hazard management slope stability study related to the railway system in Canada are also reported. The study took advantage of recent research on unsaturated soil behaviour and applied this information to real-time modelling of climatic conditions. The quantification of the water balance at the ground surface, and subsequent infiltration, is used as the primary tool for hazard level assessment. The suggested hazard model can be applied at either specific high risk locations or in a more general, broad-based manner over large areas. A more thorough understanding of unsaturated soil behaviour as it applies to near ground surface soils, along with the numerical computational power of the computer has made it possible for new approaches to be used in slope hazard management engineering.展开更多
The turn-key construction project is implemented in Taiwan not by a single company but by a make-shift group of several companies. Hence,problems to coordinate the professional construction management (PCM) and the su...The turn-key construction project is implemented in Taiwan not by a single company but by a make-shift group of several companies. Hence,problems to coordinate the professional construction management (PCM) and the supervising architectural company often occur for the lack of long-term experience to work together. The various factors that affect the implementation of turn-key projects currently practiced in Taiwan are analyzed using the analytic network process (ANP). The objective is to study how the twelve key factors in the four layers of "Role assignment","Signing contract","Operational procedures" and "Losing capital investment" affect the progress of implementing the turn-key project in Taiwan. The results reveal that "Delay in payment" has the most negative influence with 15.62% weighing factor; "Latent risk" comes next with 11.14% weighing factor,and "Responsibility of construction company for project quality" is the third with 10.79% weighing factor.展开更多
Deformation and dislocations of segments of shield tunnel in construction stage have apparent effect on tunnel structure stress and even cause local cracks and breakage in tunnel. 3D finite element method was used to ...Deformation and dislocations of segments of shield tunnel in construction stage have apparent effect on tunnel structure stress and even cause local cracks and breakage in tunnel. 3D finite element method was used to analyze two segment ring models under uniform injected pressure: (1) segment ring without wedge-shaped segment, which has 16 types of preinstall erection tolerance; (2) segment ring with wedge-shaped segment, which has no preinstall erection tolerance. The analysis results indicate that different erection tolerances can cause irregular deformation in segment ring under uniform injected pressure, and that the tolerance values are enlarged further. Wedge-shaped segment apparently affects the overall deformation of segment ring without erection tolerances. The uniform injected pressure can cause deformation of ring with wedge-shaped segment irregular, and dislocations also appear in this situation. The stress of segment with erection tolerances is much larger than that of segment without erection tolerances. Enlarging the central angle of wedge-shaped segment can make the irregular deformation and dis- locations of segments smaller. The analysis results also provide basis for erection tolerance control and improvement of segment constitution.展开更多
There are progressive architects, engineers, contractors and owners that adopt some of the newest technologies for financial benefits. The moving force to integrate BIM (building information modeling) tools may come...There are progressive architects, engineers, contractors and owners that adopt some of the newest technologies for financial benefits. The moving force to integrate BIM (building information modeling) tools may come from owners demanding a BIM deliverable to approve the work on these projects. Ifa contractor can produce this deliverable, then obtaining the project could be done in a more convincing way. Contractors are confronted with problems in selecting proper construction methods and applying their knowledge about specific and well-defined technologies to a project. Their decision-making process and better project outcomes can be improved through a database-oriented library of construction methods and therefore, a consistent methodology to classify construction methods is needed. This goal can be achieved by introducing rigorous construction method descriptors. The technology solution and the trending need of owners to pay software companies to develop software that really works for them and contractors are empirically proved in this paper through a technology ontology and BIM-enabled estimating procedure. An exploratory case study is presented. This way, owners can efficiently demand deliverables that can be utilized by them downstream, allowing contractors and subcontracting trades to work efficiently and to assure the daily flow of operations.展开更多
Prediction of roadheader performance plays a significant role in the plan of tunnel construction, which is influenced by different key parameters, including rock strength, discontinuity in rock mass, type and specific...Prediction of roadheader performance plays a significant role in the plan of tunnel construction, which is influenced by different key parameters, including rock strength, discontinuity in rock mass, type and specifications of roadheader machine, and brittleness. The main aim of this study is to build a robust empirical equation based on rock mass properties for the roadheader performance prediction. For achieving the aim, a dataset composed of roadheader performance rate and rock properties is established using the dataset compiled from an underground coal mine located in a remote rugged desert environment some 85 km south of Tabas City in mid east Iran. By using gathered data, the statistical analyses are conducted between rock mass properties and roadheader performance to find whether there is a significant relationship between input variables and roadheader performance. The results show that rock mass properties have a considerable impact on the rate of the roadheader performance. It is demonstrated that the proposed model can accurately predict the roadheader performance as a function of rock mass properties.展开更多
Alternative contracting techniques have been frequently used in highway construction in the United State and have played an important role in the effort to improve construction project performance. However, it is stil...Alternative contracting techniques have been frequently used in highway construction in the United State and have played an important role in the effort to improve construction project performance. However, it is still unknown whether which project factors have significant influence on project performance. It is essential to learn from the experiences and opinions of construction project managers who had executed innovative or alternative contracts in order to improve and refine the usage of alternative contracting methods. Innovative contracting methods have been used by state Departments of Transportation for many years, so there is now sufficient data to measure the effectiveness of these innovations. Working under a grant from the Florida Department of Transportation (FDOT), the research team used the experiences and opinions of construction field engineers who had executed innovative contracts on FDOT projects to measure the effectiveness of these systems. To that end, interviews were conducted with FDOT and consultant personnel from across Florida. All interviewed were project managers who had overseen at least one project using an innovative contracting method. Discussions brought enthusiastic responses from those interviewed, both for and against certain innovations. This paper will focus on the experiences and opinions of those experienced construction field engineers dealing with well-known innovations, as well as newer innovations such as "Detour Rental" and "Damage Recovery".展开更多
Concern for the environmental impact of organizations' activities has led to the recognition and demand for organizations to manage and report on their carbon footprint. However, there is no limit as to the areas of ...Concern for the environmental impact of organizations' activities has led to the recognition and demand for organizations to manage and report on their carbon footprint. However, there is no limit as to the areas of carbon footprints required in such annual environmental reports. To deliver improvements in the quality of carbon footprint management and reporting, there is a need to identify the main elements of carbon footprint strategy that can be endorsed, supported and encouraged by facility managers. The study investigates carbon footprint elements managed and reported upon by facility manager in the UK. Drawing on a questionnaire survey of 256 facility managers in the UK, the key elements of carbon footprints identified in carbon footprint reports are examined. The findings indicate that the main elements are building energy consumption, waste disposal and water consumption. Business travel in terms of using public transport, air travel and company cars are also recognized as important targets and objectives for the carbon footprint strategy of several FM (facilities management) organizations.展开更多
This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,...This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,concept design and combined basic design. The key technologies are the researches concerning global design,system integration,platform positioning,global performance analysis,structural strength and fatigue analysis,environment effect assessment of South China Sea,basin test and tunnel test,and construction technology of platform. Core technology of design and construction for the 6th deep water semi-submersible rig is held. Independent detail design and construction are also accomplished. These have improved technology of key equipment for China offshore oil exploitation.展开更多
The Korea Water Resources Corporation (K-Water) has encountered four problems during the management of water resources of approximately 1,300 buildings spread throughout the country-degradation, budget constraints, ...The Korea Water Resources Corporation (K-Water) has encountered four problems during the management of water resources of approximately 1,300 buildings spread throughout the country-degradation, budget constraints, lack of standards, and lack of planning. In this study, we have developed a mechanism for collecting, maintaining, and analyzing ground data for repair and replacement works. Our BMS (building maintenance system) uses the recorded repair and replacement work histories and calculates the life cycle costs of the related items. Further, it enables the performance of repair and replacement tasks through an integrated approach aimed at preventive maintenance. In this manner, the BMS is expected to maximize the efficiency of the formulation of prevention and maintenance work plans, monitoring of work histories, predictions of future tasks from the analyses of repair and replacement histories, and performance of LCC (life cycle cost) calculations. Reliable maintenance of national properties can thus be achieved by using the BMS, which promotes reasonable and efficient repair and replacement activities.展开更多
According to Brazilian reports of large trucks accidents on Federal Highway, fatigue and speeding are the major contributors to those accidents in which drivers are trying to meet short delivery deadlines for long hau...According to Brazilian reports of large trucks accidents on Federal Highway, fatigue and speeding are the major contributors to those accidents in which drivers are trying to meet short delivery deadlines for long hauls. A new federal law has been approved to limit truck drivers' working times, including maximum continuous driving time and maximum daily and weekly on-duty time. We present a study that aims at analyzing whether the existing resting areas on federal highways have sufficient capacity to meet current and future demand for truck stops. We have established the following method: In the first step, we review and study different models found in the literature and evaluate their potential application to Brazilian conditions; In the next step, we develop our own model and, finally, validate it using data from BR-101 Federal Highway, in Santa Catarina State. Tests made using part of collected data (which were subjected to statistical treatment) showed satisfactory results, indicating that the demand behavior was consistent with that observed in the field and the answers provided by truck drivers in the interviews. The research has yet to complete processing all data and it also must be repeated in other regions with different characteristics.展开更多
A new process for the co-production of vinyl acetate monomer and acetic acid from ethane feedstock was studied. Various configurations were proposed and simulation results were given for each case to optimize process ...A new process for the co-production of vinyl acetate monomer and acetic acid from ethane feedstock was studied. Various configurations were proposed and simulation results were given for each case to optimize process variables. This new process offers an overall yield values above 70% with minimum separation steps involved and the possibility of utilities integration. The process does not involve any CO production, thus becoming environmentally more favorable. The initial capital investment of the proposed process is much lower compared to the conventional route.展开更多
文摘Weather-related geo-hazards are a major concern for both natural slopes and man-made slopes and embankments. Government agencies and private companies are increasingly required to ensure that there is adequate protection of sloping sur- faces in order that interaction with the climate does not produce instability. Superior theoretical formulations and computer tools are now available to address engineering design issues related to the near ground surface soil-atmospheric interactions. An ex- ample is given in this paper that illustrates the consequences of not paying adequate attention to the hazards of slope stability prior to the construction of a highway in South America. On the other hand, examples are given from Hong Kong and China's Mainland where significant benefits are derived from putting in place a hazard slope stability management system. Some results from a hazard management slope stability study related to the railway system in Canada are also reported. The study took advantage of recent research on unsaturated soil behaviour and applied this information to real-time modelling of climatic conditions. The quantification of the water balance at the ground surface, and subsequent infiltration, is used as the primary tool for hazard level assessment. The suggested hazard model can be applied at either specific high risk locations or in a more general, broad-based manner over large areas. A more thorough understanding of unsaturated soil behaviour as it applies to near ground surface soils, along with the numerical computational power of the computer has made it possible for new approaches to be used in slope hazard management engineering.
文摘The turn-key construction project is implemented in Taiwan not by a single company but by a make-shift group of several companies. Hence,problems to coordinate the professional construction management (PCM) and the supervising architectural company often occur for the lack of long-term experience to work together. The various factors that affect the implementation of turn-key projects currently practiced in Taiwan are analyzed using the analytic network process (ANP). The objective is to study how the twelve key factors in the four layers of "Role assignment","Signing contract","Operational procedures" and "Losing capital investment" affect the progress of implementing the turn-key project in Taiwan. The results reveal that "Delay in payment" has the most negative influence with 15.62% weighing factor; "Latent risk" comes next with 11.14% weighing factor,and "Responsibility of construction company for project quality" is the third with 10.79% weighing factor.
文摘Deformation and dislocations of segments of shield tunnel in construction stage have apparent effect on tunnel structure stress and even cause local cracks and breakage in tunnel. 3D finite element method was used to analyze two segment ring models under uniform injected pressure: (1) segment ring without wedge-shaped segment, which has 16 types of preinstall erection tolerance; (2) segment ring with wedge-shaped segment, which has no preinstall erection tolerance. The analysis results indicate that different erection tolerances can cause irregular deformation in segment ring under uniform injected pressure, and that the tolerance values are enlarged further. Wedge-shaped segment apparently affects the overall deformation of segment ring without erection tolerances. The uniform injected pressure can cause deformation of ring with wedge-shaped segment irregular, and dislocations also appear in this situation. The stress of segment with erection tolerances is much larger than that of segment without erection tolerances. Enlarging the central angle of wedge-shaped segment can make the irregular deformation and dis- locations of segments smaller. The analysis results also provide basis for erection tolerance control and improvement of segment constitution.
文摘There are progressive architects, engineers, contractors and owners that adopt some of the newest technologies for financial benefits. The moving force to integrate BIM (building information modeling) tools may come from owners demanding a BIM deliverable to approve the work on these projects. Ifa contractor can produce this deliverable, then obtaining the project could be done in a more convincing way. Contractors are confronted with problems in selecting proper construction methods and applying their knowledge about specific and well-defined technologies to a project. Their decision-making process and better project outcomes can be improved through a database-oriented library of construction methods and therefore, a consistent methodology to classify construction methods is needed. This goal can be achieved by introducing rigorous construction method descriptors. The technology solution and the trending need of owners to pay software companies to develop software that really works for them and contractors are empirically proved in this paper through a technology ontology and BIM-enabled estimating procedure. An exploratory case study is presented. This way, owners can efficiently demand deliverables that can be utilized by them downstream, allowing contractors and subcontracting trades to work efficiently and to assure the daily flow of operations.
文摘Prediction of roadheader performance plays a significant role in the plan of tunnel construction, which is influenced by different key parameters, including rock strength, discontinuity in rock mass, type and specifications of roadheader machine, and brittleness. The main aim of this study is to build a robust empirical equation based on rock mass properties for the roadheader performance prediction. For achieving the aim, a dataset composed of roadheader performance rate and rock properties is established using the dataset compiled from an underground coal mine located in a remote rugged desert environment some 85 km south of Tabas City in mid east Iran. By using gathered data, the statistical analyses are conducted between rock mass properties and roadheader performance to find whether there is a significant relationship between input variables and roadheader performance. The results show that rock mass properties have a considerable impact on the rate of the roadheader performance. It is demonstrated that the proposed model can accurately predict the roadheader performance as a function of rock mass properties.
文摘Alternative contracting techniques have been frequently used in highway construction in the United State and have played an important role in the effort to improve construction project performance. However, it is still unknown whether which project factors have significant influence on project performance. It is essential to learn from the experiences and opinions of construction project managers who had executed innovative or alternative contracts in order to improve and refine the usage of alternative contracting methods. Innovative contracting methods have been used by state Departments of Transportation for many years, so there is now sufficient data to measure the effectiveness of these innovations. Working under a grant from the Florida Department of Transportation (FDOT), the research team used the experiences and opinions of construction field engineers who had executed innovative contracts on FDOT projects to measure the effectiveness of these systems. To that end, interviews were conducted with FDOT and consultant personnel from across Florida. All interviewed were project managers who had overseen at least one project using an innovative contracting method. Discussions brought enthusiastic responses from those interviewed, both for and against certain innovations. This paper will focus on the experiences and opinions of those experienced construction field engineers dealing with well-known innovations, as well as newer innovations such as "Detour Rental" and "Damage Recovery".
文摘Concern for the environmental impact of organizations' activities has led to the recognition and demand for organizations to manage and report on their carbon footprint. However, there is no limit as to the areas of carbon footprints required in such annual environmental reports. To deliver improvements in the quality of carbon footprint management and reporting, there is a need to identify the main elements of carbon footprint strategy that can be endorsed, supported and encouraged by facility managers. The study investigates carbon footprint elements managed and reported upon by facility manager in the UK. Drawing on a questionnaire survey of 256 facility managers in the UK, the key elements of carbon footprints identified in carbon footprint reports are examined. The findings indicate that the main elements are building energy consumption, waste disposal and water consumption. Business travel in terms of using public transport, air travel and company cars are also recognized as important targets and objectives for the carbon footprint strategy of several FM (facilities management) organizations.
基金National "863"Program "The study of 3000m depth water semi-submersible drilling rig key technology"( No.2006AA09A103)
文摘This paper focuses on the independent design and construction of HYSY981. HYSY981,which China National Offshore Oil Corporation(CNOOC) possesses its intellectual property right,is brought forward by advanced research,concept design and combined basic design. The key technologies are the researches concerning global design,system integration,platform positioning,global performance analysis,structural strength and fatigue analysis,environment effect assessment of South China Sea,basin test and tunnel test,and construction technology of platform. Core technology of design and construction for the 6th deep water semi-submersible rig is held. Independent detail design and construction are also accomplished. These have improved technology of key equipment for China offshore oil exploitation.
文摘The Korea Water Resources Corporation (K-Water) has encountered four problems during the management of water resources of approximately 1,300 buildings spread throughout the country-degradation, budget constraints, lack of standards, and lack of planning. In this study, we have developed a mechanism for collecting, maintaining, and analyzing ground data for repair and replacement works. Our BMS (building maintenance system) uses the recorded repair and replacement work histories and calculates the life cycle costs of the related items. Further, it enables the performance of repair and replacement tasks through an integrated approach aimed at preventive maintenance. In this manner, the BMS is expected to maximize the efficiency of the formulation of prevention and maintenance work plans, monitoring of work histories, predictions of future tasks from the analyses of repair and replacement histories, and performance of LCC (life cycle cost) calculations. Reliable maintenance of national properties can thus be achieved by using the BMS, which promotes reasonable and efficient repair and replacement activities.
文摘According to Brazilian reports of large trucks accidents on Federal Highway, fatigue and speeding are the major contributors to those accidents in which drivers are trying to meet short delivery deadlines for long hauls. A new federal law has been approved to limit truck drivers' working times, including maximum continuous driving time and maximum daily and weekly on-duty time. We present a study that aims at analyzing whether the existing resting areas on federal highways have sufficient capacity to meet current and future demand for truck stops. We have established the following method: In the first step, we review and study different models found in the literature and evaluate their potential application to Brazilian conditions; In the next step, we develop our own model and, finally, validate it using data from BR-101 Federal Highway, in Santa Catarina State. Tests made using part of collected data (which were subjected to statistical treatment) showed satisfactory results, indicating that the demand behavior was consistent with that observed in the field and the answers provided by truck drivers in the interviews. The research has yet to complete processing all data and it also must be repeated in other regions with different characteristics.
文摘A new process for the co-production of vinyl acetate monomer and acetic acid from ethane feedstock was studied. Various configurations were proposed and simulation results were given for each case to optimize process variables. This new process offers an overall yield values above 70% with minimum separation steps involved and the possibility of utilities integration. The process does not involve any CO production, thus becoming environmentally more favorable. The initial capital investment of the proposed process is much lower compared to the conventional route.