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Blast resistance evaluation of urban utility tunnel reinforced with BFRP bars

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Defence Technology（防务技术） 2021年第2期17卷 512-530页

作者： Qiang Zhou Hu-guang He San-feng Liu Xiao-shuo Chen Ze-xun Tang Yang Liu Zhen-yu Qiu Sen-sen Li He Wang Yin-zhi Zhou Jian-nan Zhou Hua-lin Fan Feng-nian Jin State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing210007China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing210016China

To improve corrosion-resistance of shallow-buried concrete urban utility tunnels(UUTs),basalt fiber reinforced polymer(BFRP)bars are applied to reinforce *** the UUT must have excellent survival capability under accidental explosions,a shallow-buried BFRP bars reinforced UUT(BBRU)was designed and *** blast experiments were carried out on this *** responses,damage evolutions and failure styles of the BBRU under repetitive explosions were *** tunnel roof is the most vulnerable component and longitudinal cracks develop along the *** the scaled distance is larger than 1.10 m/kg1/3,no cracks are observed in the *** the BBRU is severely damaged,there are five cracks forming and developing along the *** roof is simplified as a clamped-supported one-way slab,proved by the observation that the maximum strain of the transverse bar is much larger than that of the longitudinal *** responses of the roof slab are predicted by dynamic Euler beam theory,which can consistently predict the roof displacement under large-scaleddistance *** with the UUT reinforced with steel bars,the BBRU has advantages in blast resistance with smaller deflections and more evenly-distributed cracks when the scaled distance is smaller than 1.260 m/kg1/3 and the steel bars enter plastic *** elastic defamation of the BFRP bars endows the UUT more excellent blast resistance under small-scaled-distance explosions.

关键词： utility tunnel BFRP bars Explosion Dynamic response Crack Dynamic theory

Seismic behaviors of utility tunnel-soil system: With and without joint connections

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Underground Space 2022年第5期7卷 798-811页

作者： Liang Han Hanlong Liu Wengang Zhang Xuanming Ding Zhixiong Chen Li Feng Zhenyu Wang School of Civil Engineering Chongqing UniversityChongqing 400044China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400044China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400044China Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao 266590China

Seismic responses of utility tunnel-soil system were studied via shaking table model tests with considerations of two kinds of double box utility tunnels:with and without joint *** two testing utility tunnel models were made of galvanized iron wire and micro-concrete,and the ground was simulated by the dry standard sand through layered tamping *** utility tunnel-soil system was subjected to horizontal vibration in uniaxial direction perpendicular to the longitudinal direction of tunnel *** instrumentations of earth pressure gauges,accelerometers and strain gauges,the earth pressure response,acceleration response and bending moment response were *** testing results show that the joint connections in the utility tunnel along the longitudinal direction play an important role in determining the characteristic of earth pressure response and bending moment response,whereas the effect of joint connections on acceleration response is less *** addition,the partition wall exhibits the consistent acceleration response with the side-wall of double box utility tunnel model under seismic *** on the testing results,it is suggested that the joint connection should be taken reasonably into consideration during design and construction for engineering practice.

关键词： utility tunnel Joint connections Seismic behaviors Shaking table Model test

Dynamic-Response Analysis of the Branch System of a utility tunnel Subjected to Near-Fault and Far-Field Ground Motions in Different Input Mechanisms

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Computer Modeling in Engineering & Sciences 2022年第1期130卷 167-186页

作者： Yuhang Jin Endong Guo Houli Wu Peilei Yan Institute of Engineering Mechanics China Earthquake AdministrationHarbin150080China Key Laboratory of Earthquake Engineering and Engineering Vibration Harbin150080China

There are few studies on the dynamic-response mechanism of near-fault and far-field ground motions for large underground structures,especially for the branch joint of a utility tunnel(UT)and its internal *** on the theory of a 3D viscous-spring artificial boundary,this paper deduced the equivalent nodal force when a P wave and an SV wave were vertically incident at the same time and transformed the ground motion into an equivalent nodal force using a self-developed MATLAB program,which was applied to an ABAQUS finite element *** on near-fault and far-field groundmotions obtained fromtheNGA-WEST2 database,the dynamic responses of a utility tunnel and its internal pipeline in different inputmechanisms of near-fault and far-field groundmotions were compared according to bidirectional input and tridirectional input,***,the damage to the utility tunnel caused by the near-fault ground motion was stronger than that caused by the far-field ground motion,and the vertical ground motion of near-fault ground motion aggravated the damage to the utility *** addition,the joint dislocation of the upper and lower three-way joints of the pipeline in the branch systemunder the seismic action led to local stress *** general,the branch system of the utility tunnel had good seismic performance to resist the designed earthquake action and protect the internal pipeline fromdamage during the rare earthquake.

关键词： Dynamic response utility tunnel near-fault ground motion far-field ground motion earthquake input seismic design

Dynamic response of utility tunnel during the passage of Rayleigh waves

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Earthquake Science 2010年第1期23卷 13-24页

作者： Jie Li Qingxia Yue Jun Chen State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China School of Civil Engineering Shandong Jianzhu University Ji'nan 250101 China

The modeling methodologies and calculation of dynamic response of underground structure under Rayleigh waves is investigated in this paper. First the free field responses under Rayleigh waves are analyzed and the numerical results agree well with the theoretical results. Then, the approximate Rayleigh waves are put forward based on the preliminary re- search, and Rayleigh wave field is obtained through fast Fourier transform technique. Taking a utility tunnel as an example, its dynamic responses under Rayleigh waves is calculated by ABAQUS. The results demonstrate that bending deformation is the main component of structural deformation and the deformation at the top of the structure is about twice as much as that at bottom of the structure. The effect of soil-structure interface and the buried depth of underground structure are also investi- gated via parameter analysis. For the shallow buffed underground structures, Rayleigh waves can be the key factor to control the responses and damage of the structure.

关键词： utility tunnel Rayleigh wave dynamic response fast Fourier transform

Seismic response of underground utility tunnels: shaking table testing and FEM analysis

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 555-567页

作者： Jiang Luzhen Chen Jun Li Jie State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China Department of Building Engineering Tongji University Shanghai 200092 China

Underground utility tunnels are widely used in urban areas throughout the world for lifeline networks due to their easy maintenance and environmental protection capabilities. However, knowledge about their seismic performance is still quite limited and seismic design procedures are not included in current design codes. This paper describes a series of shaking table tests the authors performed on a scaled utility tunnel model to explore its performance under earthquake excitation. Details of the experimental setup are first presented focusing on aspects such as the design of the soil container, scaled structural model, sensor array arrangement and test procedure. The main observations from the test program, including structural response, soil response, soil-structure interaction and earth pressure, are summarized and discussed. Further, a finite element model （FEM） of the test utility tunnel is established where the nonlinear soil properties are modeled by the Drucker- Prager constitutive model; the master-slave surface mechanism is employed to simulate the soil-structure dynamic interaction; and the confining effect of the laminar shear box to soil is considered by proper boundary modeling. The results from the numerical model are compared with experiment measurements in terms of displacement, acceleration and amplification factor of the structural model and the soil. The comparison shows that the numerical results match the experimental measurements quite well. The validated numerical model can be adopted for further analysis.

关键词： lifeline system utility tunnel shaking table test finite element method soil-structure interaction

Bamboo Winding Composite utility tunnels:a case study on mechanical behavior with WSN monitoring and numerical simulation

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Low-carbon Materials and Green Construction 2023年第1期1卷 241-253页

作者： Hengdong Wang Jiawei Wang Xin Xie Fei Wang Shanghai Municipal Engineering Design Institute(Group)Co. Ltd901 North Zhongshan 2Nd RdShanghai 200092China Tongji University Shanghai Institute of Disaster Prevention&Relief1239 Siping RdShanghai 200092China

Bamboo Winding Composite Pipes(BWCPs)have many advantages such as good mechanical properties,low cost,low carbon,environmental friendliness,thermal insulation and easy installation et *** present,BWCP is widely used in urban water supply,drainage,communication cable protection,farmland irrigation *** is obvious that the Bamboo Winding Composite materials have good application prospects in the field of utility ***,considering that the size of utility tunnels is much larger than that of normal pipelines,the wide application of Bamboo Composite utility tunnels(BCUTs)is still a *** this paper,the force performance of BCUT in Datong Shanxi Province,was studied using two methods:real time monitoring and numerical *** sensor networks were used for monitoring,and the real time monitoring data of horizontal convergence and strains under the condition of backfill were *** monitoring data indicated that the horizontal convergence can meet the requirement of relevant technical standards.A three-dimensional numerical model of the utility tunnel was established using FEM *** influence of soil parameters on the deformation and strain of the BCUT was studied using the numerical *** simulation results were compared with real-time monitoring *** soil parameters K_(0) and k_(sh) have significant effects on the deformation,stress and strain of the utility *** kind of utility tunnel is recommended to use in areas with relatively good geological conditions.

关键词： utility tunnel Biomaterials Real time monitoring Wireless sensor networks Numerical simulation

Long rectangular box jacking project:A case

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Underground Space 2021年第2期6卷 101-125页

作者： Xiaolong Chen Baosong Ma Mohammad Najafi Peng Zhang College of Engineering China University of Geosciences–WuhanNo.388 Lumo RoadWuhanHubei ProvinceChina Center of Underground Infrastructure Research and Education(CUIRE) The University of Texas at ArlingtonBox 19308ArlingtonTXUSA

Rectangular pipe jacking or box jacking has become more popular in municipal applications because of its better adaptability to shallow overburdens and its higher structural section utilization than the conventional circular pipe *** case study presents a utility tunnel constructed by using rectangular box jacking in Suzhou,*** utility tunnel,which has a cross section of 9.1 m in width and 5.5 m in height,was jacked 233.6 m,which is the longest known single jacking length of a rectangular box jacking project in *** box jacking mainly passed through a silty sand layer with high groundwater levels with a minimum depth of cover of only 3.5 m underneath the Yuanhetang *** this zone,the structures on the surface are sensitive to external disturbance,thus increasing the challenges of construction.A series of measures were taken during the jacking process,and the project was successfully *** paper provides an overview of this project and introduces key techniques in the construction of working shafts as well as in the installation and retrieval of the box jacking *** addition,the use of lubrication to reduce friction resistance,navigation and application of an anti-buoyancy slab under the Yuanhetang River,and analyses of soil deformation caused by box jacking are described.

关键词： utility tunnel Rectangular box jacking Lubrication and friction resistance reduction technology Anti-buoyancy slab Ground deformation

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使用者介入PPP项目的激励机制研究