Zhong X.,Chelbi Engineering Consultants Inc.
Proceedings - 2010 International Conference on Optoelectronics and Image Processing, ICOIP 2010 | Year: 2010
Road safety audit and speed management concepts have been accepted as valuable tools for traffic safety. These two new concepts have been separately applied successfully in some projects in recent years in China. Form the aspect of traffic safety, the two concepts coincide as in nature. But few projects have been integrated with the two concepts to improve safety. The paper will describe how to combine safety audit with speed management in detail design stage and in pre-opening and trial operation stage for QL Freeway. The objective of the paper is to present how to introduce speed management in safety audit process, to discuss the problems of typical technique and successful experience during application of the two concepts. © 2010 IEEE.
Chai Z.,China Academy of Transportation Science |
Liu T.,Chelbi Engineering Consultants Inc. |
Cao J.,RoadMainT Co.
Applied Mechanics and Materials | Year: 2013
Pavement reflective cracking performance depends not only on layer material characteristics, but also on layer interface conditions. One way to potentially enhance cracking resistance is by applying a specially designed polymer modified asphalt emulsion (PMAE) at the interface. PMAE residue wicks up into mixture voids and creates an asphalt-rich mix near the interface, defined as bonded interface, which is more than an adhesive film. Therefore, shear strength tests, which can well characterize the adhesive film effect along the interface, cannot fully capture the effect of bonding agents on cracking across the interface. In order to evaluate the effect of interface conditions on cracking performance, a composite specimen interface cracking (CSIC) test was developed. This test was designed to initiate and propagate a crack from one material layer through the interface into the other material layer(s). The characteristics of bonded interfaces, CSIC test, and some results obtained from CSIC tests were presented in this paper. Results show that CSIC test is an effective tool to evaluate the effects of interface conditions on reflective cracking performance. © (2013) Trans Tech Publications, Switzerland.
Dong Z.,Chelbi Engineering Consultants Inc. |
Zheng P.,China Communications Construction Company Ltd.
Modern Tunnelling Technology | Year: 2013
The Gujiashan tunnel on the Beijing-Kunming G5 line of the national highway network is a karst tunnel and is characterized by many deep and narrow vertical karst fissures, karst troughs, and karst ditches. Such measures as backfilling, reinforcement, and bridging were adopted for this project, and advance support with φ75 mm large-diameter self-drilling rock bolts was widely applied in the construction of the Gujiashan tunnel.
You Q.,Tongji University |
Zheng N.,Changan University |
Shi G.,Chelbi Engineering Consultants Inc.
Advanced Materials Research | Year: 2011
Flexible pavements comprise a majority part of highways in china. Many highway bridges are constructed in these highways. These primary highway bridges are subjected to the same heavy loading as the conventional asphalt pavement, but caused much more significant damage than the conventional asphalt pavement. As hot-mix asphalt (HMA) is a visco-elastic material and the all around environment is different between road pavement and bridge deck, the structural or load-carrying capacity of road pavement and bridge deck is different. Thus, to accurately determine in situ strength characteristics of flexible pavement, it is necessary to predict the temperature distribution within the HMA layers and find the difference between road pavement and bridge deck. The majority of previously published research concentrated on pavement temperature prediction. To confirm the bridge deck temperature profile, observing the temperature at bridge deck and road pavement for two months. Compared with the temperature profile of bridge deck and road pavement, find the difference between them. Then some daily temperature prediction models are analyzed and develop a modified double-sine model to simulate the surface temperature variation of bridge deck. © (2011) Trans Tech Publications.
Shui C.,Beijing Jiaotong University |
Shui C.,Chelbi Engineering Consultants Inc. |
Dong Y.,Beijing Jiaotong University
Beijing Jiaotong Daxue Xuebao/Journal of Beijing Jiaotong University | Year: 2012
Regional division is the most important problem when the government formulates regional transportation policies. This paper offers the methods and ideas of bi-level regional division model based on perspective on transportation. Focus on economic, social and transport development level, regional research and operability of policy formulating, etc, we select and establish a reasonable index system that reflects the regional economy, transportation, urbanization and other factors, and use fuzzy clustering analysis to classify. On the basis of above, the paper selects regional accessibility as index for analysis. Then it researches the regional division plan, and analyzes characteristics of the economic and transportation, which provides references for regional transportation policy formulating.