浅谈建设公路工程项目管理控制

由于建设公路工程项目自身的特点,决定了建设公路工程项目控制的工作重点在于其进度、成本及质量等指标。作为甲方,希望从技术、经济、合同等方面,通过对公路工程项目全过程的有效控制,减少成本,提高投资效益和社会效益。本文着重对甲方在建设公路工程的管理模式进行讨论。

BOT融资模式在公路建设中的应用研究

随着公路建设的发展,公路建设资金的募集显得尤为重要,由于建设资金的有限,这就使得我们能够允许更多的其他资本进入建设市场,这样就产生了许多新的投、融资模式,BOT是其中较为成功的一种。通过实例说明BOT投融资模式在公路建设中的应用。

对建设工程项目概算与招标文件计量支付的分析

本文主要分析的是对公路建设项目设计概算内容和招标文件组成、概算编制程序和计量支付体系进行了比较,探索了目前政府交通主管部门与建设单位之间、建设单位与承包商之间在项目造价控制上分别采用的行政管理与合同管理手段的区别,并提出问题及建议。

公路沥青路面检测方法分析

将沥青方式投入到路面建设工程中可以有效简短工期,避免额外的人员、材料浪费,为公路建设作业的施工质量和施工效率提供了保障。但同时也对公路建设的后期检测工作提出了更高要求。近些年来,随着我国科技水平不断提高进步,公路沥青路面的检测方法有了很大的进步,这对于加快公路建设速度、检验公路施工水平具有很大的积极意义。

Changes in permafrost environments caused by construction and maintenance of Qinghai-Tibet Highway

The sideward permafrost along the Qinghai-Tibet Highway (QTH) contains massive ground-ice and is at a relatively high temperature.Under the influence of the steady increase of human activities,the permafrost environment has been changed greatly for a long time.At present,the permafrost becomes warm and rapidly degenerates,including the decline of the permafrost table,rising of the ground temperature,shortening of the length of frozen section,and extension of range of melting region.Some thaw hazards (e.g.thaw slumping and thermokarst pond) have widely occurred along both sides of the roadbed.In addition,due to the incomplete construction management,the vegetation adjacent to the highway is seriously damaged or eradicated,resulting in the land desertification and ecosystem out of balance.The dust,waste and garbage brought by drivers,passengers,maintenance workers,and transportations may also pollute the permafrost environment.

Study on range interval distance of prestressed anchor bars using update backpropagation neural network

Taking the practical reinforced engineering of a reinforced soil retaining wall as an example, which located in Shandong Province and set on 104 national highway, the stress spread behaviors of the anchor bars in the preforced proceeding were tested. According to the test data, and by use of the update backpropagation (BP) algorithm neural network(NN), the test method and it’s mechanism were studied by the network, then the learning results show the mean square error(MSE) only at the 2 55% level, and the proof testing results show the MSE at 4 38% level (the main aim is to build a NN directly from the in situ test results (the learning phase)). Ipso facto, the learning and adjustment abilities of the NN permit us to develop the test data, subsequently, 36 test data were acquired from the NN. By use of the provide data, as well as the failure situation and carried loading capacity of the retaining wall, finally, the choice the reasonable range interval distance of prestress cement grouting anchor bars were carried out, and the result was 2 m×2 m.

Changes in distribution area of Korean musk deer(Moschus moschiferus parvipes) from 1950s to 1999 in South Korea

Based on the literature reviews and questionnaire, field survey on the species, feces, and tracks in non-snow season and snow season of Korean musk deer from February to December of 1999 in South Korea (Cultural Properties Administration 1999), the authors summarized the change of distribution area and number of Korean musk deer from 1950s to 1999. The results showed that the distribution area of Korean musk deer (Moschus moschiferus parvipes) was sharply decreased from 1950s to 1999 in South Korea. Due to the road and forest road construction in the habitat of Korean musk deer, the musk deer habitats were fragmented and lost. And the illegal capture for economic benefits was the main reason of decreases in number of indi-viduals and habitats of this species. Forest roads in high elevation area were also used as the passages for illegal captures. For the conservation and protection of Korean musk deer, strict regulation of illegal capture is urgently needed.

Stability Problems in Road and Pipeline Constructions and Their Mitigation——Examples from Sakhalin and Azerbaijan

The paper gives two examples of larger construction projects with typical stability problems. The first example is from Sakhalin Island in the Russian Far East. It is connected with a construction of oil and gas pipelines through the mountainous terrain in Makarov region. The region has an active geotectonic history and is highly affected by uncontrolled erosion and extensive landslips. Basic principles of landslide hazard mitigation are presented. The second example is from a motorway construction in Azerbaijan. This motorway leads from Baku to Russia through a seismo-tectonically active area at the toe of Caucasian mountains and in some places is situated in deep cuts at the toe of high slopes. This unsuitable routing, together with seismic activity, led to a slope stability failure of a slope affected by recent tectonic movements near the village of Devechi. Stability conditions and designed remedy measures are presented.

Preliminary study on the highway-related human activities

In this paper, highway-related human activities are defined as well as the human activities related to highway for keeping a normal production and livelihood. They include highway research, highway education, highway legislation, administration of justice of highway case and enforce the law, assessment, planning, design, construction and management, decision-making of highway projects. Therefore, highway-related human activities are not equal to construction of highway projects.

Stability analysis of slope in strain-softening soils using local arc-length solution scheme

Soils with strain-softening behavior — manifesting as a reduction of strength with increasing plastic strain — are commonly found in the natural environment. For slopes in these soils,a progressive failure mechanism can occur due to a reduction of strength with increasing strain. Finite element method based numerical approaches have been widely performed for simulating such failure mechanism,owning to their ability for tracing the formation and development of the localized shear strain. However,the reliability of the currently used approaches are often affected by poor convergence or significant mesh-dependency,and their applicability is limited by the use of complicated soil models. This paper aims to overcome these limitations by developing a finite element approach using a local arc-length controlled iterative algorithm as the solution strategy. In the proposed finite element approach,the soils are simulated with an elastoplastic constitutive model in conjunction with the Mohr-Coulomb yield function. The strain-softening behavior is represented by a piece-wise linearrelationship between the Mohr-Coulomb strength parameters and the deviatoric plastic strain. To assess the reliability of the proposed finite element approach,comparisons of the numerical solutions obtained by different finite element methods and meshes with various qualities are presented. Moreover,a landslide triggered by excavation in a real expressway construction project is analyzed by the presented finite element approach to demonstrate its applicability for practical engineering problems.

Analysis of Risk Factors for Highway Construction Projects in Egypt

Egypt construction projects are associated with different levels of risks. The lack of familiarity of project management standards is one of the common risks in the construction industry in Egypt. The main aim of this paper is to identify the most significant risk factors affecting highway construction project in Egypt to decrease the likelihood and impact of those risks. The research method starts with extensive literature review to provide a prime risk factors list which was also augmented to expertise to reach final risk factor list which contains all risks that may be faced during highway construction. Subsequently, a set of 12 risk groups consisting of 73 risks was selected and a questionnaire survey was conducted to determine the likelihood and consequences of the identified risks. Later, a software application was developed using MATLAB to facilitate risk evaluation of highways projects. Results indicated that the risk factors arise from owner side is one of the most common risk factors in the construction industry in Egypt as the owner in the majority of construction project in Egypt is the governmental sector, however, the overall project risk of highway construction projects in Egypt is considered as at a medium level.

Use of Innovative Contracting Methods by Dots - Project Managers Speak

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＂.

Fatigue behaviour of welded joints assembled by longitudinal corrugated plates

Fatigue is usually the cause for the cracks identified at bridge elements in service. With an increase in the introduction of corrugated steel web girders in recent highway bridge construction, the understanding of the fatigue behaviour of welded details in such structures becomes an important issue for the design. The typical welded details were represented as welded joints assembled by longitudinal corrugated plates. All the experiments were performed under fatigue loading using a servo-control testing machine. The test results from the failure mode observation with the aid of infrared thermo-graph technology show that the failure manner of these welded joints is comparable to that of the corrugated steel web beams reported previously. It is indicated from the stiffness degradation analysis that the welded joints with larger corrugation angle have higher stiffness and greater stiffness degradation in the notable stiffness degradation range. It is shown from the test S-N relations based on the free regression and forced regression analyses that there is a good linear dependence between lg(N) and lg(ΔS). It is also demonstrated that the proposed fracture mechanics analytical model is able to give a prediction slightly lower but on the safe side for the mean stresses at 2 million cycles of the test welded joints.

High Logistics Cost, Toll Road and Institutional Factors Countermeasure in China

Logistics industry has become the driving force of economic growth. However, the logistics industry develops very slowly because the institutional factors have critically hindered the whole development of logistics industry in China. Institutional factors are regarded as the important factor for logistics cost under the market segmentation of peasant mentality. By comparison of the institutional costs in United States, Japan, India and the Europe, deep reason of high cost behind cost driving force is analyzed. Countermeasure is put forward, such as reducing the prices of domestic toll road, using fuel tax as implemented for highway construction funds, and decreasing the restricted policy for carrying freight cars etc..

Wave-electric field coupling imaging diagnostic method for filled subgrade

Thick earth-rock filled embankment of large earthwork volume often occurs during the construction of expressways in mountainous and hilly areas. The compaction quality of earth-rock filled subgrade will directly affect the settlement deformation and stability of the embankment after filled. Therefore, effective evaluation on the compaction quality of the earth-rock filled subgrade is an unsolved critical technical issue to control the construction quality of highway engineering. Based on the wave propagation and electrical resistivity characteristics of the earth and rock fillings, a theoretical model of the compaction quality detection by wave-electric field coupling imaging diagnostic method was established. Then, two filled subgrade models containing cavities and heterogeneous bodies respectively were make separately, and by the wave velocity testing and electrical resistivity testing, the wave-electric field coupling imaging diagnostic method was applied to these two model. The result shows that it is feasible to use the wave testing technique and the electrical resistivity testing technique for a diagnostic test of the subgrade compaction quality. Based on the abnormal areas reflected by the wave velocity imaging and electrical resistivity imaging results, we are able to analyze the scope and site of distress but not able to quantitatively evaluate the subgrade compaction quality. We can accurately qualitatively analyze the subgrade compaction quality based on the wave-electric field coupling calculation model of fill subgrade quality proposed by this paper.

Traffic Impact on Incentive Contracting Project Time Performance during Highway Construction

The volume of highway traffic in the United States continues to increase. In the face of this there is a concomitant need to improve and repair transportation infrastructure. Construction frequently requires a reduction in capacity during construction activity; consequently road users as well as adjacent businesses must endure the delays and inconveniences associated with transportation construction. Recognizing the problems that construction can produce, state highway agencies （SHAs） have continually sought ways to minimize the negative impact from their construction operations. Incentive contracting has played an important role in this effort to improve project performance. The Florida Department of Transportation （FDOT） is one of the leading SHAs using such innovative contracting methods as Incentive/Disincentive （I/D）, A＋B （cost plus time bidding） combined with I/D, No Excuse Bonus, and Liquidated Savings. This paper analyzes the traffic impact on incentive project time performance using highway construction projects recently completed in Florida. Project data obtained from FDOT were evaluated using time performance indices. A survey of traffic impact on project work types was performed in Florida in order to evaluate the relationship between construction project types and road traffic influence during construction. Based on the survey results, the 38 most frequently used work types in Florida during the study period were categorized into three traffic impact levels： （1） high traffic impact, （2） medium traffic impact, and （3） low traffic impact. Statistical analysis was performed. The results show that there are significant differences on project time performance between low and high impact levels as well as low and medium impact levels.

Landscape and Road Integration in Greece

This paper concerns the Strategic Environmental Assessment of the construction of some major Greek motorways： the Ionia Motorway, the Peloponnese Motorway and the Athens-Lamia Motorway. In the beginning the natural and cultural diversity of the Greek landscape as well as its conservation needs are discussed. The landscape impact assessment methodology consists of the identification of environmental goals, of sensitive landscape parameters, of environmental indicators and of acceptable impact thresholds. The selection of alternative solutions as well as of mitigation measures has been studied, on the basis of relevant environmental indicators. The developed methodology may constitute a tool for the environmental management of other road programs of great scale.

Green Highway for Malaysia： A Literature Review

This paper reviewed on the green highway definition and green highway terminology to improve knowledge and awareness of green highway for highway construction projects. Moreover, this paper discussed briefly on the rating system for green highway by highlighting various eight rating systems for green highway. This study adopted the secondary data from previous research and findings on green highway construction from all over the world. With regard to published articles on green highways, the outcome of the paper will examine several major issues in green highway which are the definition of green highway, terminology used for green highway aspects, green highway initiatives and green highway rating systems from all over the world.

Evaluation of Social Environment Impact of Highway Construction Using Gray Matter-Element Information Entropy Model

Due to the importance of the social environment impact of highway construction project, an advanced evaluation is required to incorporate situations such as uncertainty, incompatibility and less information. This paper proposes a gray matter-element evaluation model based on the information entropy. The model is developed by combining both quantitative and qualitative methods, using probability theory to convert quantitative index to qualitative index, and the weight of those indexes were determined through synthesised integral weighting method, integrating matter-element theory, grey theory, and information theory. The model is then applied to evaluate the impact of the social environmental impact of highway construction project which will provide support for decision makers. Cheng-Yu highway and Shen-Da highway were selected for model application, and good results were achieved similar to the real situation.

Reasons for a Cultural Renovation of the Road Infrastructure Design

Built environments are undergoing a state of crisis, due to fragmentation and obsolescence： consolidated urban areas, suburbs and fringe areas require to be restored so as to recover a sense of vivid places and to avoid segregation. Fabric of routes and voids can be considered as a medium in order to structure a landscape, to manage and govern a region, to nurture its unique subculture. A structure of bonds is to be designed to promote a rapid and safe movement of resources, of people, of ideas, even from and to most remote sites. Infrastructure can foster a vast economic development, and also, a profound social and cultural development.