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Zhang K.,Wuhan University of Technology | Zhao X.,Wuhan University of Technology | Liang X.,Dalian Municipal Design and Research Institute Co. | Liu W.,Hubei Provincial Expressway Group Co.
Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering) | Year: 2010

The thesis takes a single-tower cable-stayed bridge as an example, by means of structural detection, measurement of cable tension, loading test and combined with finite-element model modification method, reasonably evaluates the cable-stayed bridge's health situation and load-bearing capacity, then puts forward the reason resulting in the main disease of the bridge is unreasonable cable tension during construction which caused stress redistribution of the original structure, and then provides credible basis for bridge reinforcement, maintenance and management.

Zeng S.,Harbin Institute of Technology | Gao L.,Harbin Institute of Technology | Chen S.,Harbin Institute of Technology | Wang C.,Dalian Municipal Design and Research Institute Co.
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2016

In this study, a pushover method was proposed to estimate the elastic-plastic seismic response of concrete-filled steel tube (CFT) arch bridge. Since the seismic response of CFT arch bridge may be significantly affected by the high-order modes, the combination of multiple modals should be taken into account in the pushover method. Firstly, the application procedures of the multi-modal pushover method were elaborated. Then the Chaobai River Bridge was taken as an example, the incremental dynamic analysis (IDA) curves obtained from the multi-modal pushover method and the elastic-plastic time-history analysis of tie-bar model of the bridge were compared. The comparison results show that the maximum response of the structure can be appropriately obtained by the multi-modal pushover method, and the IDA curves obtained by the multi-modal pushover method are close to those obtained by the elastic-plastic time-history analysis, indicating that the method can be applied to engineering practice. For the present example, it was found that the errors for multi-modal combination are 10%~15% smaller than those for single modal. © 2016, Editorial Office of China Civil Engineering Journal. All right reserved.

Jiang K.,Tongji University | Jiang K.,Dalian Municipal Design and Research Institute Co. | Xia C.,Tongji University
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2010

In order to guarantee security when tunnel construction and study the stability of tunnel surrounding rock, some site monitoring and measurements have been performed in Kuiqi tunnel #2. Based on the analyses of measured data, the distribution characteristics and variation laws of the ground settlement, crown settlement and convergence around the tunnel, the displacement of the interior of surrounding rock, bolt axial forces and pressure of surrounding rocks and preliminary support are all studied. The study results are drawn to provide the basis for modifying and optimizing the design and construction scheme. This study will offer some useful references for the design, construction and monitoring of tunnels in the similar geological conditions.

Jiang K.,Tongji University | Jiang K.,Dalian Municipal Design and Research Institute Co. | Xia C.-C.,Tongji University | Bian Y.-W.,Tongji University
Yantu Lixue/Rock and Soil Mechanics | Year: 2012

According to the construction conditions of Kuiqi No.2 small-space tunnel with super-large cross-section and eight traffic lanes in the second phase project of Fuzhou International Airport Highway, a discrete element analysis program is established to simulate the construction process. In the program, the double-heading construction method, CRD method and CD method have been simulated. The settlements of vault, horizontal deformations of middle rock pillar, horizontal deformations of surrounding rock and plastic zone of surrounding rock are analyzed and the advantages of the three methods are compared. Considering the characteristics of Kuiqi No.2 Tunnel, the practical construction scheme is optimized. The double-heading method is changed to CRD method at the tunnel entrance. The modification of construction method has great contribution to cut down the cost and to reduce erection time. The results provide some reasonable references to design and construction for similar engineering.

Sun H.-W.,Lanzhou Jiaotong University | Sun H.-W.,Beijing University of Technology | Guo Y.,Lanzhou Jiaotong University | Peng Y.-Z.,Beijing University of Technology | Xie H.-G.,Dalian Municipal Design and Research Institute Co.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2013

The landfill leachate treatment was investigated by using an UASB-SBR biological system. The long-term stability of nitrogen removal via nitrite at normal and low temperature was studied. Furthermore, the achievement mechanism of partial nitrification and characteristic of nitrifying bacteria were investigated in SBR. 598days experimental result showed that the removal efficiencies of COD, NH4 +-N and TN reached 92.0%, 99.2% and 98.0%, respectively. The advanced nitrogen removal was achieved in the system. Partial nitrification was achieved after 116days operation in SBR, and nitrite accumulation ratio (NAR) reached above 90%. The higher NAR was maintained for 171days at low 15°C and the lowest temperature of 10.2°C during two winters. The effect of free ammonia (FA) inhibition and process control was used to achieve nitrite pathway in the SBR. The ammonia oxidizing bacteria (AOB) was dominant by fluorescence in situ hybridization (FISH) techniques analysis, and the spherical Nitrosococcus and rod-shaped Nitrosomonas were dominant in ammonia oxidizing bacteria by scanning electron microscope (SEM) techniques analysis.

Sun H.W.,Lanzhou Jiaotong University | Bai Y.,Lanzhou Jiaotong University | Peng Y.Z.,Beijing University of Technology | Xie H.G.,Dalian Municipal Design and Research Institute Co. | Shi X.N.,China International Engineering Institute for Light Industry Co.
Water Science and Technology | Year: 2013

In this study, a biological system consisting of an up-flow anaerobic sludge blanket (UASB) and anoxic-oxic (A/O) reactor was established for the advanced treatment of high ammonium urban landfill leachate. The inhibitory effect of free ammonia (FA) and free nitrous acid (FNA) on the nitrifying bacterial activity was used to achieve stable nitritation in the A/O reactor. The results demonstrated that the biological system achieved chemical oxygen demand (COD), total nitrogen (TN) and NH4 +-N removal efficiencies of 95.3, 84.6 and 99.2%, respectively at a low carbon-to-nitrogen ratio of 3:1. Simultaneous denitritation and methanogenesis in the UASB could improve the removal of COD and TN. Nitritation with above 90% nitrite accumulation was successfully achieved in the A/O reactor by synergetic inhibition of FA and FNA on the activity of nitrite oxidizing bacteria (NOB). Fluorescence in situ hybridization (FISH) analysis showed that ammonia oxidizing bacteria (AOB) was dominant and was considered to be responsible for the satisfactory nitritation performance. © IWA Publishing 2013.

Li Z.-X.,Dalian Ocean University | Zhang L.,Dalian Ocean University | Chen X.-B.,Dalian Municipal Design and Research Institute Co. | Li H.,Dalian Ocean University | Li D.,Dalian Ocean University
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2015

The performance of biological nitrogen removal in treating seawater-containing wastewater is not satisfying. Here we report the acclimation of a freshwater-origin anaerobic ammonium oxidation (anammox) sludge by using seawater with increasing salt concentrations. Nitrogen removal performance, morphological characteristics and dominant strains of the bacterial community in the reactor were investigated. After 145days of acclimation, this freshwater-origin anammox sludge was fully adapted to seawater, with a total nitrogen removal rate (TNRR) reaching 2.80 kgN/(m3·d). The anaerobic ammonium oxidizing rate first increased, then decreased, and then increased again when the seawater content was gradually increased from 0‰ to 30‰. A seawater content of 20‰ was the critical point during the acclimation. In terms of morphological characteristics, cell shape of the acclimated anammox bacteria was irregular and pilus-like appendages were developed on the cell wall. Change in the bacterial community composition after acclimation was also observed through DGGE.The dominant anammox strain was identified as "Candidatus Kuenenia Stuttgartiensis" based on the sequence of the 16S rDNA gene. ©, 2015, Chinese Society for Environmental Sciences. All right reserved.

Li H.,Dalian Ocean University | Li H.,Dalian Municipal Design and Research Institute CO. | Zhang L.,Dalian Ocean University | Li Z.X.,Dalian Ocean University
Applied Mechanics and Materials | Year: 2014

Anaerobic ammonium oxidation (anammox) process is a heated researched biotechnology for nitrogen removal in wastewater. The application of the process is limited due to its long start-up time and sensitivity to organic matters. This paper discussed the effects of butyrate on anammox process. The nitrogen removal rate of anammox process was elevated at low butyrate content (1 mmol/L) and decreased at high butyrate content (3 mmol/L). NH4+ -N:NO2- -N:NO3- -N:butyrate ratio was 1:1.25:0.08:0.04 and 1:7.26:0.10:1.85 when butyrate concentration was 1 mmol/L and 3 mmol/L. © (2014) Trans Tech Publications, Switzerland. All Rights Reserved.

Zhang T.,Dalian Municipal Design and Research Institute Co.
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2015

According to construction of Dadongshan one-bore four-lanes tunnel in Dalian, the monitoring analysis of tunnel deformation and the pressure is carried out, which reveals the mechanical response characteristics of small clear spacing tunnel with super-large section. It is shown that the excavation of CRD I and Two Side-wall Pilot 1 department is of great influence on the vault settlements of left-upper pilot tunnel. The deformation caused by the two departments is 50%~60%, 50%~65% of the total respectively. For tunnel with super-large section, the deformation and pressure can be well controlled by closing the support timely, using the reasonable methods and auxiliary measures. The pressure inside of the small clear spacing tunnel is more complicated than the outside and the stress states of existing tunnel is lower than the following tunnel. Thus the influence caused by the following tunnel should be fully considered in design and construction stage. The results can be adopted in the design, construction and research of similar tunnels. ©, 2015, Editorial Office of China Civil Engineering Journal. All right reserved.

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