Journal of Railway Engineering Society

关闭×

The mobile platform

Office Online

Journal Online

Forthcoming Articles

Download Articles

Member Service

2016 Vol. 33, No. 1 Published: 2016-01-15

Geology and Subgrade Railway and Rail Bridge Engineering Tunnel Engineering Survey and Design Urban Rail Construction

Survey and Design

	1	Research on the Three - dimensional Geological Modeling Technology for Railway BIM - based Design
		LIU Yi - qin，YANG Xu – kun
		Research purposes: Based on the three - dimensional modeling and visualization technology，railway BIM - based design implements virtual construction of the subgrades， bridges， tunnels， stations and buildings. Three - dimensional geological modeling is a kind of technology，which supports the interaction between geological experts and computer software and hardware， deducing the geological conditions of a piece of three - dimensional space， forming three - dimensional geological model， and visualizing the model in computer. In this paper， three - dimensional simulation of railway engineering geological conditions is achieved based on the three - dimensional geological modeling technology，which can provide three - dimensional geological information services for the railway BIM - based design. Research conclusions ：( 1) Three - dimensional simulation of railway engineering geological conditions is of specialty， so the traditional three - dimensional geological modeling technology in the mineral and energy fields is not suitable. The three - dimensional geological modeling technology with the linear borehole in this paper achieves the three - dimensional simulation of engineering geological conditionsin railway bridge section effectively. ( 3 ) The research results can provide the three - dimensional geological information for railway BIM - based design.
		2016 Vol. 33 (1): 1-4 [Abstract] ( 2767 ) HTML (1 KB) PDF (830 KB) ( 2514 )

Geology and Subgrade

	5	Environmental Risk Assessment of Underground Water Level Falling Induced by Construction in Mountain Tunnel ^Hot!
		BAI Ming -zhou，CHEN Yun，SHI Hai
		Research purposes： Tunnel construction has a certain impact on the ecological environment along the line. Unreasonable excavation and drainage may cause sudden water and mud bursting，as well as groundwater drainage，dry water，surface water storage capacity reduction and others phenomena affecting the surrounding ecological environment. To quantitatively study the effect of the tunnel drainage on ecological environment，this paper takes a railway tunnel as example，considering geographical， geological， hydro - geological， and tunnel project and other relevant factors， the ecological evaluation index and grading standards are determined，as well as using Analytic Hierarchy Process to decide the weight of each index value. Finally using Fuzzy Analytic Hierarchy Process evaluates the ecological environment impact assessment on groundwater discharge. Research conclusions:(1) The risk evaluation index of the impact of the groundwater level on the ecological environment is established，and the fuzzy comprehensive evaluation method is used to evaluate the ecological environment. The results show that comprehensive evaluation index average number is 2.69， which means that groundwater seepage caused by tunnel construction and adverse impact on the ecological environment. (2 ) From the dynamic point of view， the monitoring of the groundwater level is carried out. The effect of tunnel drainage on the groundwater level decreased is revealed and the results of fuzzy comprehensive evaluation are verified. ( 3 ) The research results can provide the guidance for safe construction of mountain tunnel and the control of karat water.
		2016 Vol. 33 (1): 5-10 [Abstract] ( 2805 ) HTML (1 KB) PDF (1459 KB) ( 2601 )

	11	A Stability Analysis Method ofthe Overhanging Crag with Longitudinal Cracks
		CUI Hong - huan1，LIU Jian - kun1，ZHANG Li - qun2，HAN Hui - xun3
		Research purposes: There are a number of boulders exposed on the surface of steep slopes along the railway line，when the high - speed railway is constructed in mountain areas where volcanic and sedimentary rocks are widely distributed. Some overhanging rocks may develop longitudinal cracks because of erosion， differential weathering and other factors. These dangerous rock mass with different sizes and shapes will bring about the great security risk to the construction and operation of high - speed railways. Unfortunately， there was no logical and rational method to meet actual conditions of the overhanging crag with longitudinal cracks. So the method of calculating the safety factor should be studied timely for stability of crags to make technical support for reinforcement and prevention of unstable rocks along the railway in the mountains. Research conclusions:(1) The new model which is based on overhanging portion of the rock body beside longitudinal crack indicates that the ultimate tensile strength of rock is assumed to be the determination basis for analysis of its stability. ( 2 ) A new analysis software is developed on the basis of the stability analysis model which is established in the plane coordinate system for a crag with longitudinal cracks. ( 3 " The research is applied for stability of quartz sandstone crags by searching the most dangerous potential fracture planes at the exit of Benxi tunnel in the Passenger Line from Shenyang to Dandong, and the minimum safety factor of overhanging crags is obtained. (4) The research result can provide a valuable engineering basis for design of slope at Benxi tunnel exit.
		2016 Vol. 33 (1): 11-15 [Abstract] ( 2756 ) HTML (1 KB) PDF (1114 KB) ( 2485 )

	16	Research on the Stress Characteristics ofTransverse Static Pressure with Compaction Technology on Loss Foundation
		MI Wei - jun1，JIA Yan2，QU Yao - hui1，WU Xiao - peng1
		Research purposes ： The traditional treatment method of collapsible loss foundation，such as shock， ramming，sinking，blasting， cannot be used in small space and narrow site. Based on the special requirements of foundation treatment standard for grade A building and small space，the newly developed equipment non - vibration - lateral hydrostatic extrusion device， using the method of lateral static pressure compaction， converts the vertical hydraulic power to a horizontal force applied to the soil around the dense cone in the process of extruding and forming， and produces compression deformation of the soil to achieve the compaction effect. Non - vibration - lateral hydrostatic extrusion device is cone -shaped， and extrusion hole is completed in the opening and closing process of extrusion element to transform radius and vertical shrinkage of the guide element. Research conclusions:( 1 ) In the process of extrusion， the surrounding soil is presented as an elastic plastic deformation， the stress characteristics accord with the small hole expansion theory and the limit equilibrium theory. (2) When the pore size of 0. 41 m is reached， the hydraulic pressure of the power unit of the extrusion device is 231.35 kN，the horizontal force of the soil is 903. 07 kN after transformed into horizontal force. ( 3 ) The vertical hydraulic pressure is completely balanced with the soil，and does not need the vertical impact force and vertical gravity weight in the whole process, which can also achieve the miniaturization, portability and operability of the construction Equipment. (4)The research achievements can be used to provide theoretical basis and technical support for non - vibration compacting process in collapsible loess foundation.
		2016 Vol. 33 (1): 16-20 [Abstract] ( 2718 ) HTML (1 KB) PDF (702 KB) ( 2451 )

	21	Experimental Research on the Factors Influencing Strength of Cement Mixed Saturated Loss
		YANG You - hai1，LIU Yong - he1，REN Xin2
		Research purposes: The soft soil foundation strengthened by cement mixing pile can effectively improve the ground bearing capacity and reduce the settlement. However，the strength and behavior are greatly influenced by soil， etc. Therefore， based on the saturated loss foundation engineering with cement mixing pile of railway project for Lanzhou to Zhongchuan Airport，the factors， such as mixing ratio of cement to fly ash (lime - fly ash )，age，fly ash incorporation，cement strength grade，organic content and mixing uniformity， which influence the strength of cement mixed saturated loss are studied. Research conclusions :( 1 ) The strength of cement mixed saturated loss increases with the increase of lime - fly ash ratio and age，and the strength of 90 d age increases by 0. 9 times when the lime - fly ash ratio increases from 12% to 20% . (2 ) In the certain total incorporation，the strength of cement mixed saturated loss decreases with increase of fly ash，and the rational and economical ratio of fly ash to cement is 1 : 2. ( 3 )The strength of cement mixed saturated loss increases significantly when the strength of cement is rated from P.O 32. 5 to P.O 42. 5 % and for 90 d age, the strength of saturated loss mixed with cement P.O 42. 5 is superior to cement P.O 32. 5 by 40% to 50 %. ( 4 ) The strength of cement mixed saturated loess decreases with the increase of organic content in soil. ( 5 ) The mixing uniformity influences the strength of cement mixed saturated loss significantly, especially in the certain incorporation of lime - fly ash, thus the uniformity of cement mixed loss must be ensured so as to reinforce the saturated loss foundation by cement mixing pile. (6) The research conclusions can provide basis and reference for design and parameter selection of saturated loss foundation construction of express railway.
		2016 Vol. 33 (1): 21-25 [Abstract] ( 2765 ) HTML (1 KB) PDF (767 KB) ( 2522 )

	26	The Deformation Characteristics Analysis of Scattered Insequent Landslide Reinforced by Prestressed Anchor Cables
		HAN Kan1，MA Hui - min2，SI Xiao - dong3
		Research purposes :A large number of mountainous highways under construction and that is already built involve cutting slope engineering problems. Through monitoring of deep horizontal displacement and surface displacement，the exact position of the slide surface was found，analyzing the whole deformation process scattered on the body and turn into landslide without retaining after slope excavation， to provide a basis for emergency design of landslide. Through analyzing the amount of deformation observation data of scattered in sequent landslide，the landslide displacement characteristics before and after rock reinforcement were obtained. Research conclusions :( 1 ) The deformation characteristics of the scattered in sequent landslide are scattered in front， slip in after，the landslides are generally converted by scattered together. Landslide attaches scattered body and the slide zone part attaches to scattered zone. (2 ) Through monitoring data，the exact position of tiie slide surface was found，the whole displacement development and changes of scattered landslide were monitored and truly described. ( 3 ) The landslide retaining arrangement prestressed anchor can take the initiative to protect the slope and play a significant reinforcing effect to broken rock and landslide deformation. (4) The research result can provide a basis to landslide emergency design and win the time for the landslide protection， and provide reference and empirical criteria for the construction and design of this kind of slope.
		2016 Vol. 33 (1): 26-29 [Abstract] ( 2792 ) HTML (1 KB) PDF (1063 KB) ( 2439 )

Railway and Rail

	30	Research on the Key Parameters of Plane and Profile for Heavy Haul Railway ^Hot!
		LONG Xu - you1，SHI Jin2，WANG Ying - jie2
		Research purposes： Heavy haul transportation has been internationally recognized as the direction of the development of railway freight. At present the track alignment of heavy haul railway is lack of system research，and the corresponding standard is based on * Code for Design of Railway Line”，which focuses primarily on mixed passenger and freight railway. This paper investigated the key parameters of plane and profile for heavy haul railway line based on the current practical situations and construction requirements of heavy haul railway，and then the recommended values were proposed. Research conclusions :( 1) The minimum curve radius of heavy haul railway should not be less than 800 m at the speed of 120 km/h. ( 2 ) The minimum length of intermediate straight line should be greater than 0. 6 v on the general conditions and 0. 3 v on the difficult conditions，no matter the reverse curve is on the bridge or the general subgrade section. ( 3 ) The profile slope of the curve may not be reduced on curved track or tunnel sections when the slope is less than 6. 9‰ for the million - ton train with the traction by two locomotives. ( 4 ) Since the maximum force of freight car coupler caused by the algebraic difference between adjacent gradients of adjacent grade section is less than the carrying capacity of the coupler，the maximum algebraic difference between adjacent gradients could not be restricted. (5) The minimum length of grade section for heavy haul railway could be consistent with the design standard for ordinary railway. (6 ) The research results can provide scientific reference for parameter selection of track alignment of heavy haul railway.
		2016 Vol. 33 (1): 30-35 [Abstract] ( 2939 ) HTML (1 KB) PDF (1091 KB) ( 2519 )

	36	Study on the Minimum Curve Radius of Heavy Haul Railway ^Hot!
		SUN Hai – fu
		Research purposes ： The choice of minimum curve radius is one of the main technical standards of heavy haul railway. Because of high axle load of heavy haul railway，large volume，serious rail wear compared with the conventional railway passenger and freight transportation， the choice of minimum curve radius is directly related to the safety， economy and convenience of maintenance of heavy haul railway. Through research on technical standards， combined with the construction，operational experience and scientific research results of heavy haul railway in our country in recent years，the standard of minimum curve radius selection for heavy haul railway is proposed，which has a strong reference value and guidance for the construction of heavy haul railway in China. Research conclusions:( 1 ) The choice of curve radius should be adapted to local conditions， reasonable selection， which can meet the requirements of the driving speed，and can also adapt to the terrain geological conditions，reduce the investment，to facilitate maintenance and repair. (2 ) The choice of curve radius of heavy haul railway should pay attention to the wheel rail wear，and reduce the maintenance workload of line，to create better conditions for operations. (3 ) The minimum curve radius of heavy haul railway is not less than 1 200 m，not less than 800 m under difficult conditions，and not less than 600 m under the individual condition. (4) The research results can provide a theoretical basis for the research of the heavy haul railway，and provide a reference for the selection of the main technical standards of the heavy haul railway.
		2016 Vol. 33 (1): 36-41 [Abstract] ( 2748 ) HTML (1 KB) PDF (870 KB) ( 2511 )

	42	Dynamic Analysis of Minimum Curve Radius on Heavy Haul Railway ^Hot!
		ZENG Yong1，XU You - ding1，YI Si - rong2，YAN Hua1
		Research purposes : The minimum curve radius is one of major technical standards on heavy haul railway， impacting on running safety and stability of the heavy haul vehicle. On the basis of the research at home and abroad on the minimum curve radius of heavy haul railway， a vehicle - track dynamic model on the curve section of heavy haul railway is established based on the dynamics theory and dynamic characteristics of the vehicle - track system on heavy haul railway in different curve radius conditions are analyzed by the model. Then the influence law of curve radius on vehicle - track dynamic performance is studied. Research conclusions :( 1) The curve radius of the heavy haul railway has varying degrees of impact on running safety and stability of heavy haul vehicle，wheel - rail interaction and wheel - rail wear of heavy haul railway. (2) When the radius of curve is less than 800 m，vehicle - track dynamic performance will be decreased rapidly on the condition of reducing the radius of curve , When the radius of curve is more than 1 000 m，vehicle - track dynamic performance will be improved in a certain degree while increasing the radius of curve，but the improvement is limited; Especially，when the radius of curve is more than 1 500 m，the change of the radius of curve has little effect on vehicle - track dynamic performance. (3) It is suggested that the minimum curve radius of heavy haul railway is 1 000 m on general conditions and on difficult conditions 800 m is allowed. (4) The radius of curve should be not less than 1 500 m as far as possible while designing heavy haul railway line. (5) The research result can provide a reference to design the curve of heavy haul railway and formulate related normative documents.
		2016 Vol. 33 (1): 42-45 [Abstract] ( 2844 ) HTML (1 KB) PDF (532 KB) ( 2555 )

	46	Effects of Wheel and Rail Wear on Wheel/Rail Contact Behavior in Turnout Zone ^Hot!
		WANG Ping，LIU Zhe
		Research purposes :For the serious wear problems happened between wheel and switch rail， the actual profiles of worn LM type wheel and worn switch rail in the operating routes have been measured by the Shanghai Meichi station as test background. Based on the wheel - rail contact traces princij^le and finite element theory， the contact problem between wheel and switch rail was solved， and the effects of worn profiles on wheel and switch rail^s contact geometry relationship，contact stress， size of contact patch and Von Mises stress were analyzed， which provides the theoretical basis for the profiles optimization and grinding of switch rail. Research conclusions :( 1) Because of the worn profiles of wheel and switch rail，the distribution of wheel - rail contact points have been changed，the wheel load transition range has been shorten and the amplitude and fluctuation of wheel - rail contact vertical irregularity have been increased，which has increased the wheel - rail interaction and makes the wear damage more serious in turnout zone. (2) The wear can improve the contact comfort between the wheel and rail，and reduce the wheel - rail contact stress and Von Mises stress. (3) The maximum Von Mises stress of the switch rail occurs within the range from 2. 7 mm to 4. 5 mm under the rail surface， where the contact fatigue cracks can be easily generated. (4) The research results can provide the guidance for the profiles optimization of switch rail.
		2016 Vol. 33 (1): 46-51 [Abstract] ( 2776 ) HTML (1 KB) PDF (1525 KB) ( 2465 )

	52	Monitoring Data Management Information System for Ballastless Track Turnout on Elevated Station
		CAI Xiao-pei，GAO Liang，LIU Chao，ZHENG Cheng，XIE Tao， SUN Guo –li
		Research purposes: Long - term monitoring system of high - speed railway infrastructure is developed to monitor the structure mechanical characteristics and deterioration behavior in real - time and ensure the safety and stability of high - speed trains. For the monitoring system which has the characteristics of multiple testing index，high sample frequency and large volume of data，it is urgent to manage and utilize the large volume of data in efficiency by using advanced information management tools. In this paper，based on the background of 42# turnout online monitoring field on elevated station in Beijing - Shanghai High - speed Railway，the monitoring data management information system is developed. It provides the technology platform for real - time query， analysis， statistics， prediction and alarm of structure service status. Research conclusions:(1) The monitoring data management information system for ballast less track turnout on elevated station is developed based on the B/S mode. The wireless network is used to transfer data in real - time，and the data is converted into unity type by the built - in design programs. (2) Internet users can query the data online by sensor serial numbers，monitoring indexes，box area location，and they also can make integrated query on history data for multip1e index and different structure. ( 3 ) The statistical report part can carry out data analysis over the same period of different year and the weekly，monthly，yearly reports. Moreover，it has the function of the data sorting for different indexes，and the data can be exported according to user requirements. (4) Based on the BP neural network，the prediction of structure force and deformation is achieved， and the automatic warning and alarming function is established by setting the threshold parameters. (5 ) The management information system can be applied in the field of railway maintenance management and monitoring technology， and it can provide the guidance for safety operation of the infrastructure in high -speed railway.
		2016 Vol. 33 (1): 52-57 [Abstract] ( 2933 ) HTML (1 KB) PDF (1341 KB) ( 2556 )

Bridge Engineering

	58	Longitudinal Deformation Control of Unit Slab Non - ballast Track on Continuous Beam Bridge ^Hot!
		CHEN Rong1，MA Xu - feng1，TIAN Chun - xiang2，LUO Hua - peng1，Wang Ping1
		Research purposes :When the large span bridge lay unit slab non - ballast track，the problems of interaction between beam and rail become more complicate than the ordinary CWR， and the longitudinal deformation control is insufficient in the existing norms and application of engineering practice. The line - bridge - pier integration model of continuous welded rail is established to research the influence of the longitudinal horizontal stiffness of continuous beam bridge pier on the force and deformation of unit slab non - ballast，and put forward the non - ballast track longitudinal deformation controlling index，which can provide the theory basis for laying unit slab non - ballast track on the bridge. Research conclusions #( 1 ) Under bridge expansion load， laying out the small resistance fasteners can significantly reduce resin deformation around the boss. Under train braking load， laying out the small resistance fasteners cannot reduce resin deformation effectively. (2) Increasing the stiffness of pier cannot reduce resin deformation under bridge expansion or rail breaking load， but can obviously reduce resin deformation under train braking load， to ensure resin deformation lower than 3 mm，the resin stiffness limit is 70 kN/mm. (3) For (60 +100 +60) m continuous beam and laying out constant resistance fasteners, it is required to lay rail expansion joint when rail temperature range is high than 40 F. When rail temperature range is 30 F，the pier stiffness limit is 1 800 kN/cm to meet non - ballast track strength and longitudinal deformation requirement. (4 ) The research results are helpful to design of non - ballast track on bridge.
		2016 Vol. 33 (1): 58-64 [Abstract] ( 3644 ) HTML (1 KB) PDF (1225 KB) ( 2563 )

	65	Analysis of Temperature Effect of Box Girder under Solar Radiation in Dry Cold Region ^Hot!
		SUN Wen，WU Ya - ping，JI Ri - chen
		Research purposes： In the dry and cold regions of the west China，the cracking of concrete box girder bridge under the effect of temperature variation is very serious. In this paper，in order to analyze the influence of temperature stress on the concrete box girder bridge， the distribution of sunshine temperature difference of box bridge is given according to the characteristic of box bridge temperature boundary，and the box body temperature stress is considered as nonlinear temperature difference self - constraint stress along thickness and box body lateral restraint stress. In the western dry and cold areas of high temperature differential，under the effect of temperature changes the concrete box girder bridge on the outer surface will produce larger transverse temperature stress which will lead to the emergence of longitudinal cracks in the concrete deck and have great influence on the durability of the bridge，so this paper analyzes and studies the temperature effect under the influence of solar radiation in dry and cold regions， and puts forward measures to improve crack resistance of the girder body. Research conclusions: Temperature stress is composed of the nonlinear temperature self - restrained stress and external constraint stress. The calculation shows that ： (1) Under the action of temperature difference concrete box bridge will have a considerable temperature stress, which will cause the bridge concrete cracks. ( 2 ) The temperature gradient mode Along the plate thickness direction and the temperature difference between inside and outside is the key of temperature stress calculation under the action of temperature difference of bridge . There is a certain relationship between temperature stress and the plate thickness，and temperature stress will increase with the increase of the thickness. (3 ) The research result can provide a certain theoretical basis for the engineering construction in dry cold region of high temperature differential，and has the reference significance for the prevention and treatment of diseases and improving the structure durability.
		2016 Vol. 33 (1): 65-69 [Abstract] ( 2729 ) HTML (1 KB) PDF (807 KB) ( 2475 )

	70	Seismic Response Research on the Long - span Beam - arch Composite Bridge under Rail Restraints
		DAI Gong -lian，WANG Yu
		Research purposes :For analyzing the seismic response of long - span continuous beam - arch bridge under rail restraints，taking a ( 82 + 172 +82 ) m long - span continuous beam - arch bridge on the Lanzhou - Chongqing railway as an example，the finite element model of track - bridge considering track - bridge interaction was established， the stress features of main girder，pier and track was analyzed under seismic excitation. Research conclusions ：( 1 ) The low - order longitudinal frequencies of the long - span beam - arch bridge will be increased by 30% ?50% under rail restraints. (2 ) The tracks have great influence on the displacement and internal forces of girder and pier，with maximum reduction 23.69% of internal force of fixed bearing pier. (3 ) The stress of track under seismic excitation can reach 148 MPa， so the index of rail seismic force is suggested to be added to the related railway specifications. (4)The change of rail restraints has less impact on the internal force of the pier bottom，while the increase of pier stiffness can significantly reduce the track stress under seismic action. (5 ) The research conclusions could provide some theoretical references for anti - seismic design of railway bridges across the quake zone.
		2016 Vol. 33 (1): 70-74 [Abstract] ( 2805 ) HTML (1 KB) PDF (1453 KB) ( 2482 )

	75	Researchonthe Damping Performance of the Long - spanDeckType Steel Truss Railway Arch Bridge
		ZHANG Yong - Using1，DONG Yang1，ZHU Shang - qing2，CHEN Xing - chong1，DING Ming - bo1
		Res earch purposes ： Taking a long - span steel truss railway arch bridge as the engineering background， damping performance of the steel truss arch bridge with thrust in the longitudinal， transverse direction based on the speed locking device， viscous fluid damper and BRB( buckling - restrained brace) is analyzed by adopting nonlinear time history analysis method according to structural characteristic of the steel truss arch bridge with thrust. Research conclusions :( 1) When main bridge and approach bridge are connected into a whole unit using speed locking device，damping effect for internal force of the members in arch foot section is obvious， such as damping ratio of the moment is about 20% . But damping ratio of internal force for the members in L/4 arch， crown section and column bottom section is poor，even internal force of the most of them have a greater range of increase than no damping. (2) When viscous fluid dampers are set in junction piers of main bridge，damping effect for internal force of the members in arch foot section and column bottom section is obvious，such as damping ratio of the moment is about 10%. Although damping effect of the scheme in arch foot section is less than that of the speed locking device scheme，seismic response of the members in arch ring and the column decreases to different degrees，and the phenomenon that seismic response of individual members significantly increases doesn’t appear. (3) When BRB of the K bracing are set in the Bottom and top of chord plane in main arch ring，damping effect for internal force of the members in arch foot section and column bottom section is obvious，such as damping ratio of the moment and the shear is about 10% ?20℃. But damping ratio of internal force for the members in 1/4 arch,crown section is different. Damping effect of some members is obvious,but seismic response of some members obviously increases. (4) The research results may provide references for damping design of the steel truss railway arch bridges with thrust in the high intensity earthquake zone.
		2016 Vol. 33 (1): 75-79 [Abstract] ( 2745 ) HTML (1 KB) PDF (730 KB) ( 2467 )

Tunnel Engineering

	80	Analysis of the Long - term Settlement of Immersed Tunnel with Considering K0 Consolidation of Undisturbed Soft Clay ^Hot!
		KOU Lei1，BAI Yun2
		Research purposes : The varying degrees of differential settlement appears during the operation of immersed tunnel in soft soil area，the cracking and leakage of segments caused by the excessive settlement severely impacts the operational safety of immersed tunnels. The immersed tunnel settlement in essence results from changes of mechanical properties of saturated undisturbed underwater soil caused by the disturbance of tunnel construction and the soil deformation with significant time - space characteristics under external loads. So a study is necessary to accurately calculate the values and distributions of settlement with time - space characteristics. Research conclusions :( 1) The results show that the settlement rate of outer ring immersed tunnel has maintained about 0. 001 5 mm/d，the settlement converges to steady state. (2) The thickness of salutation on top of the immersed tunnel is deeper，the development of settlement is greater，the dredging should be timely. (3 ) The settlement during the operation increases caused by the dissipation of pore water pressure in foundation layer. The reasonable treatment method of foundation layer is beneficial to reduce the settlement. (4) The research result can provide theoretical basis for the foundation problems of soft clay with time - space characteristics，and reference for optimization tunnel design and assurance operation safety of the immersed tunnel.
		2016 Vol. 33 (1): 80-86 [Abstract] ( 2695 ) HTML (1 KB) PDF (933 KB) ( 2501 )

	87	Cause Analysis of Railway Tunnel Lining Cracks and Disposal of Typical Cases
		ZHANG Min - qing，HE Zhi - jun，XIAO Guang - zhi，REN Cheng - min，JIAO Yun - zhou
		Research purposes :Railway tunnel secondary lining is the structure system to assure the safety of railway tunnel operations，once the severe cracking of secondary lining happens， safe hidden trouble of railway tunnel will be formed，and the processing of the secondary lining cracking has difficult construction， high security risk and big economic loss. Based on typical cases， this paper analyzed the cause and the treatment scheme of the three special railway tunnel under the condition of secondary lining cracks， in order to attaches great importance from design， construction and construction management，to avoid similar situation from happening again. Research conclusions ：( 1) In the special geological tunnel such as the high stress soft rock and gypsum karst breccia， the secondary lining crack has characteristics of 11 sever craze degree，wide range of paragraphs，long concealed period . (2 ) Avoid setting bell type tunnel in high stress soft rock tunnel，at the same time，should pay attention to the influence of horizontal hole，horizontal channel and shallow buried valley to the main tunnel structure，and during the design the primary support and secondary lining should be strengthened. ( 3 ) The high stress soft rock tunnel construction should strengthen the control of surrounding rock deformation，strengthen the radial grouting reinforcement，and improve the bearing capacity of the surrounding rock. Before the secondary lining should accord with standard of deformation rate control， and avoid premature bearing of secondary lining. ( 4 ) Gypsum karst breccia tunnel should give full consideration to the long - term softening effect of the groundwater seepage field distribution on surrounding rock and the expansion of the surrounding rock after tunnel runs through， and the secondary lining structure design should be strengthened. (5 ) The research results can be applied to the process of the similar tunnel.
		2016 Vol. 33 (1): 87-90 [Abstract] ( 2754 ) HTML (1 KB) PDF (819 KB) ( 2486 )

	91	Optimization Study on the Evacuation Mode for the Middle Train Compartment Fire of Single - track Tunnels ^Hot!
		LIU Song - tao1，WEI Wen - bin2，OU Chen1
		Research purposes : This paper focused on the single - track high - speed railway tunnels，based on several reasonable assumptions，theoretical evacuation model was established and the optimal evacuation path was computed. By using Pathfinder numerical simulation，numerical evacuation model of single - track high - speed railway tunnels was established，and all the evacuation paths of different train locations were analyzed，to get the optimal evacuation path. Research conclusions :( 1) Five kinds of evacuation path for the middle train compartment fire of single - track tunnels exist. (2) The optimal evacuation time of each path arranged like a line or a “ V"， and the time nodes are namely 27 m，47 m，69 m and 100 m. ( 3 ) The result of Pathfinder numerical simulation analysis was highly consistent with the theoretical evacuation model，while the highest relative tolerance was 15. 48%，and the lowest was 1.48%. (4) The research conclusions may provide theoretical basis for the evacuation design of high - speed railway tunnels，which will help to shorten evacuation time and make great difference on reducing casualties.
		2016 Vol. 33 (1): 91-96 [Abstract] ( 2849 ) HTML (1 KB) PDF (958 KB) ( 2508 )

	97	Construction Technology of High Performance Concrete in Strong Wind and Large Temperature Differential Gobi Area
		QI Hong - jun
		Research purposes : In the gobi and desert regions with biter cold， large temperature difference，strong wind，high temperature and drought，the concrete structure are more likely to produce crack or cracks is more serious， how to ensure the quality of concrete structure is a key to the high performance concrete construction. From the concrete mixture ratio design，construction management and measures and so on，this paper proposed the construction technology appropriate to environment characteristics. Research conclusions ：( 1) According to the climate characteristics，low hydration heat and low alkali content cement and mineral ultrafine powder mineral active material are used， to optimize the proportion of construction. (2) The concrete pouring time and seasonal temperature control measures are reasonably chosen， to control concrete slump， expansion degree，air content，bleeding rate and so on. (3) Under the bad natural environment，the measures such as early self - curing with mold，lightweight aggregate absorbent or SAP curing，wrapped insulation moisture curing，wind continuous filling water irrigation curing and curing with curing agent，are taken. (4) Technical measures taken in this paper have the reference for the high performance concrete construction of similar engineering.
		2016 Vol. 33 (1): 97-101 [Abstract] ( 2770 ) HTML (1 KB) PDF (738 KB) ( 2471 )

Urban Rail Construction

	102	Research on the Source Reduction of Vibration of Chengdu Museum Induced by Metro Running
		YANG Wei - guo1，LI Ming - bin2，GU Shi - qi，WANG Ming - zhu3，ZHANG Nan1，MA Bo - tao3，WANG Meng1，GEJia - qi3
		Research purposes: Chengdu Museum is close to metro line 2，so if the vibration reduction measures are not taken properly，the vibration induced by metro will adversely affect the normal use of the museum. Meanwhile，in order to meet the requirements of museum relics safety under metro vibration，based on the measured data， a three - dimensional finite element model of floating slab - tunnel - soil in MADIS/GTS is established. The tunnel wall vertical vibration is selected as a reference to measure the vibration attenuation effect of floating slab，the stiffness of steel spring and the thickness of tunnel wall. Research conclusions:(1) The floating slab could decrease vibration in high frequency band and increase vibration in low frequency band. When the stiffness of the steel spring is 6 900 kN/m，its comprehensive vibration attenuation effect is 12. 1 dB. (2) Reducing the stiffness of steel spring could effectively reduce the Z direction vibration of tunnel wall. When the stiffness of the steel spring is reduced from 9 000 kN/m to 3 000 kN/m，the Z direction vibration of tunnel wall is reduced by 5. 6 dB. (3 " Increasing the thickness of the tunnel wall could reduce the ! direction vibration of tunnel wall. When the thickness of the tunnel wall increase from 0. 2 m to 0. 8 m，the Z direction vibration of tunnel wall could reduce 2.7 dB，the effect is not obvious. (4) The research result can be applied on the source reduction of vibration induced by metro running.
		2016 Vol. 33 (1): 102-108 [Abstract] ( 2680 ) HTML (1 KB) PDF (1324 KB) ( 2472 )

	109	Cause Analysis on Damage of Adjacent Metro Shield Tunnel Due to Deep Pit Excavation with Pile - anchor Retaining
		LIU Ting - jin1，XIA Wen - yu2
		Research purposes ： Some serious damages such as segment breakage，segment cracks，leakage in joints， side ditch cracking in ballast have always been fund in the metro shield tunnel，which induced by excavation of adjacent deep foundation pit with pile - anchor retaining. It threatens metro operation and structural safety of tunnel. In this paper，by means of analyzing surrounding construction process，damage status and relative monitoring data in the actual engineering case，the causes of tunnel disease have been preliminarily investigated from excavation disturbance of adjacent foundation pit with pile - anchor retaining and the property of tunnel deformation respectively which can provide reference for similar projects. Research conclusions ：( 1 ) Soil loosing region will occur in the end of anchor owing to excavation disturbance of adjacent foundation pit with pile - anchor retaining，which could decrease the restriction ability of lateral soil and induce the deformation trend of transverse ellipse of the tunnel. Meanwhile，the increase of upper load is another reason of the trend. (2) The deformation property of transverse ellipse is the main reason of segment breakage，joints leakage in the waist of tunnel, segment longitudinal cracks in the vault of tunnel. (3) The calculation and analysis of tunnel structural safety condition show that adjacent layer of the tunnel is in the status of loose caused by the excavation of adjacent pit, the segment ring deforms according to transverse ellipse. It is preliminarily concluded that some of connecting bolt was in the state of yield. (4) The research results can be used for reference of similar engineering.
		2016 Vol. 33 (1): 109-116 [Abstract] ( 2789 ) HTML (1 KB) PDF (2027 KB) ( 2556 )

Copyright © Editorial Board of Journal of Railway Engineering Society
Supported by:Beijing Magtech