Xu J.,Beijing General Municipal Engineering Design and Research Institute
Modern Tunnelling Technology | Year: 2013
Tunnels are different underground structures in various geological conditions with high risks and complexities due to uncertainty. Since current design theory is premature, the engineering analog and empirical design principle is widely used with emphasis on dynamic design and observational construction. In reality, however, the design and construction are undertaken separately by different departments and it is difficult for them to be very well integrated, which often results in accidents or unreasonable expenditure. To promote the integration of design and construction from a management perspective, a systematic mechanism of dynamic design and observational construction is proposed, forming an overall assessment mechanism for project investment efficiency and profits.
Jiang Y.,Southwest Jiaotong University |
He C.,Southwest Jiaotong University |
Fang Y.,Southwest Jiaotong University |
Zhou J.,Beijing General Municipal Engineering Design and Research Institute
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | Year: 2013
In order to investigate the soil disturbance caused by shield tunnel construction and loading characteristics of segment lining structure in loess strata, based on the Xi'an Metro Line 2 shield tunnel passing through loess strata project, particle distinct element method had been used to simulate the vibration of ground stress and working face failure form from the meso-level. Meanwhile, dynamic tracking tests of earth pressure and structure internal force (axial force and bending moment) acting on the segment lining had been conducted to analyze the influences of earth pressure on the internal forces of segment ling during construction and later stabilization of shield tunneling. The results show that the horizontal and vertical stresses have a significant change on the top and both sides of the tunnel because of the generation of free face. Construction parameters play an important role in the internal forces of segment lining structure, especially the jack thrust and grouting pressure.
Zhao H.,Beijing General Municipal Engineering Design and Research Institute
Applied Mechanics and Materials | Year: 2013
The floating car data (FCD) is widely used to estimate the time-varying OD demands in recent years. The one of the most important factors influencing the application performance of FCD is the completeness of FCD route data. This paper is intended to develop Floyd route mending algorithm based on dynamic travel time for FCD. In this framework, the raw FCD and the processed FCD are used to identify the problem of data missing based on topological structure of the road network. Then, an approach is developed to mend route based on improved Floyd route mending algorithm based on the GIS map. The approach is designed in a way that takes full advantage of the dynamic characteristics of travel time and quick routes scan. The paper applies the proposed methodology to mend routes and derive OD demands of FCD for the Western 3rd Ring-Road corridor network in Beijing, China. It is shown from the statistical analysis that the approach is accurate and the OD demands of FCD can reflect the characteristics of OD demands of all vehicles in the road network. © (2013) Trans Tech Publications, Switzerland.
Wen G.,Xian University of Architecture and Technology |
Wen G.,Harbin Institute of Technology |
Wang S.-J.,Harbin Institute of Technology |
Wang S.-J.,Beijing General Municipal Engineering Design and Research Institute |
And 5 more authors.
Journal of Hazardous Materials | Year: 2014
Enhanced ozonation degradation of di-n-butyl phthalate (DBP) by zero-valent zinc (ZVZ) has been investigated using a semi-continuous reactor in aqueous solution. The results indicated that the combination of ozone (O3) and ZVZ showed an obvious synergetic effect, i.e. an improvement of 54.8% on DBP degradation was obtained by the O3/ZVZ process after 10min reaction compared to the cumulative effect of O3 alone and O2/ZVZ. The degradation efficiency of DBP increased gradually with the increase of ZVZ dosage, enhanced as solution pH increasing from 2.0 to 10.0, and more amount of DBP was degraded with the initial concentration of DBP arising from 0.5 to 2.0mgL-1. Recycling use of ZVZ resulted in the enhancement of DBP degradation, because the newly formed zinc oxide took part in the reaction. The mechanism investigation demonstrated that the enhancement effect was attributed to the introduction of ZVZ, which could promote the utilization of O3, enhance the formation of superoxide radical by reducing O2 via one-electron transfer, accelerate the production of hydrogen peroxide and the generation of hydroxyl radical. Additionally, the newly formed zinc oxide on ZVZ surface also contributed to the enhancement of DBP degradation in the recycling use of ZVZ. Most importantly, the O3/ZVZ process was also effective in enhanced ozonation degradation of DBP under the background of actual waters. © 2013 Elsevier B.V.
Zhao G.,Beijing General Municipal Engineering Design and Research Institute |
Zhang G.,Beijing University of Technology
Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering) | Year: 2012
Making use of the British Legion Studio 2006 foot flow simulation software as a platform, for Beijing Beiyuan transport hub design as an example, a simulation research was conducted to study the internal pedestrian transport organization and space ride of transportation hub. The results of this simulation research verified respectively the deficient and rational points existing in the designing plan of the North Station of Tiantongyuan and Beiyuan transportation hub. Through this simulation research, disadvantages and problems could be discovered and effective measures could put forward in advance. With the popularization of computer simulation technology in the area of international transportation project, micro simulation of pedestrian flow, as an effective way of research methods, will provide powerful technical support and analysis basis for the planning and designing of comprehensive transportation hub.