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Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the dynamic response of high-speed railway bridge under flood, a two-span high-speed railway simple-supported beam bridge with unequal 32-meter pier height is studied. A three-dimensional hydrodynamic model of the substructure and a finite element model of the bridge under flooding are built up to analyze the law of flow field distribution around and the hydrodynamic pressure. The influences of the change of velocity and height of flood and the foundation scour depth on the dynamic response of bridge and internal force of pile foundation are revealed. The study shows that: (1) The law of flow field distribution is basically the same when the bridge substructure is impacted by the flood with different velocities; (2) When the flood velocity exceeds 3 meters per second, the influence of the hydrodynamic pressure on the substructure cannot be ignored, and the pressure is positively correlated with velocity and height of the flood; (3) The depth of foundation scour has a significant influence on the hydrodynamic pressure. But when the depth of foundation scour is increased after the bearing platform is exposed, the increase of the pressure is not obvious; (4) When the bridge is impacted by the flood, the overall law of the dynamic response of the bridge with time is basically the same. The response is as follows: When t = 1.06 s, the lateral vibration acceleration of pier top reaches the peak value; When t = 1.16 s, the lateral displacement of pier top reaches the peak value. After the lateral displacement and vibration acceleration reach their peak values, they both tend to attenuate decay rapidly and periodically. With the velocity and height of flood increasing, the peak values and final stable values of displacement and acceleration at prier top as well as the pile bending moment increase; (5) With the increase of foundation scour depth, both the dynamic response and the pile bending moment increase, but the negative bending moment area of pile foundation is more sensitive to the impact of foundation scour depth. [ABSTRACT FROM AUTHOR]

During the long-term operation of high-speed railway in our country, affected by various factors such as surrounding environment changes and human engineering activities, large lateral deviation occurs in some line bridge sections, which seriously affects the normal and safe operation of the train and needs to be rectified urgently. Based on the analysis of the principle of bridge rectification by high pressure jet grouting, the theoretical calculation model of bridge rectification is established, and the differential equations of pile deflection, rotation angle, bending moment and shear force under the high pressure jet grouting rectification mode and the analytical formula of pier top displacement are deduced based on the elastic foundation beam theory. Then,by comparing the calculated displacement at the top of the pier with the actual offset of the line,the feasibility of high pressure jet grouting technology for bridge rectification is analyzed, and the rectification effect is verified by typical engineering cases on site. Research shows that the top displacement of pier is related to foundation coefficient and excess pore water pressure generated by high pressure jet grouting; when foundation coefficient and excess pore water pressure take 1 MPa/ m and 80.3 kPa respectively,the top theoretical calculated displacement of pier is 81.8 mm,which is much larger than the actual deviation of ballastless track line of common high speed railway;In the bridge rectification project of a high speed railway Songjiang Grand Bridge,the displacement at the top of the pier calculated by the average value of the measured excess pore water pressure 30.4 kPa 6. 4~31. 0 mm,which is also greater than the maximum deviation 18.2 mm of the line, indicating that the high pressure jet grouting technology is feasible for bridge rectification theoretically;After rectification construction,the bridge and track structure are stable,the line alignment is smooth,and there is no abnormality in the normal speed operation for many years. The theory and practice have proved that the high pressure jet grouting method is a practical and feasible technical measure for bridge rectification. [ABSTRACT FROM AUTHOR]

Solar greenhouses have been widely used in the vast western and northern regions of China, due mainly to the convenient construction and installation, low economic cost, and outstanding environmental adaptability. The slender steel can be the load-bearing components of the section-steel arched solar greenhouse to resist external loads, such as wind and snow. There are the prominent instability and disaster that caused by insufficient stiffness of solar greenhouse under extreme weather conditions, such as snowstorms. In this study, the nonlinear stability analysis was conducted on the commonly-used sectionsteel arched solar greenhouse in Hebei using elastic-plastic mechanics and nonlinear finite element (FE). A refined FE model was established for the section-steel arched solar greenhouse. The greenhouse arch roof and the vertical sections on both sides were simulated using the Beam188 element in the element library of the universal FE analysis program ANSYS. The linear elements were used to fit the circular arc segments. Diagonal tension bars, vertical brace struts, and longitudinal tie bars were all simulated using Link10 element. The bottom of the vertical sections on both sides of the arch was assumed to be consolidated with the foundation. The steel was made of Q235, with an elastic modulus of 206 GPa, a Poisson's ratio of 0.3, and a density of 7 850 kg/m³. Geometric and material nonlinearity was considered to simulate the constitutive relationship of steel using an ideal elastic-plastic model, followed by von Mises yield criterion and bilinear kinematic hardening model BKIN. The stability performance and parameter analysis of solar greenhouse structure were carried out under snow loads. The stability capacity of solar greenhouse was determined under different parameters, such as steel-section type (flat elliptical, hollow rectangular and hat-shaped cross-section), greenhouse span (8, 10, and 12 m), and snow load distribution pattern (non-uniform distribution thickness and asymmetric distribution area). There was the quantitative influence of snow load distribution on the stability capacity of solar greenhouses. The load factor-displacement curves were combined with the deformation, stress, axial, and bending moment at different points of loading time. The static instability of solar greenhouses was explored from two aspects: intuitive phenomena and intrinsic essence. The conclusions were obtained as follows: The stability capacity of the steel component with a flat elliptical section in the solar greenhouse was increased by 21.0% and 44.2%, respectively, compared with the box and hat-shaped section. There was no out of plane instability in the same cross-sectional area and flange width of the steel component. The stability capacity of solar greenhouse was rapidly reduced with the increase of span. The stability capacity of solar greenhouse under non-uniform distribution of snow loads was reduced by the maximum of 63.8%, compared with the uniform. The maximum stability capacity of a solar greenhouse increased by 9.0% and 66.8% with only tension bars and brace struts, respectively. The findings can provide the technical guidance and theoretical reference for the anti-snow loads, stability and disaster prevention in the section-steel arch solar greenhouses. [ABSTRACT FROM AUTHOR]

【Objective】Rice lodging resistance is an important trait in current rice breeding. The systematic evaluation of lodging resistance of germplasm resources is of great significance for breeding lodging-resistant varieties.【Method】200 germplasm resources in China were taken as materials, 9 traits related to lodging resistance of rice were systematically investigated, and the breeding value of these traits was evaluated by morphological clustering and path analysis.【Result】According to the lodging index, the tested materials were divided into three types: high fall-resistant type, fall-resistant type and lodging type, among which 81.5% of breeding resources had good fall-resistant ability. The correlation coefficient between stalk physical traits and lodging index of different lodging resistant germplasm resources was significantly different. The plant height, bending moment and second pitch length of restorer were positively correlated with lodging index, and the correlation coefficient between bending moment and lodging index d lodging index reached 0.789. The folding resistance of base and sheath leaf thickness were negatively correlated with lodging index, and the correlation coefficients were-0.754** and-0.659**, respectively. There was a significant positive correlation between plant height and basal segment length and lodging index, and the correlation coefficient between plant height and lodging index was 0.681**. The correlation coefficient between buckling resistance and lodging index was-0.841**.The path analysis results showed that the bending moment of the restorer line and other materials had a direct positive effect on the lodging index (Py=0.519), the plant height of the sterile line had a direct positive effect on the lodging index (Py=0.737), and the base bending force of both parents had a direct negative effect on the lodging index, with direct path coefficients of-0.331 and-0.702, respectively.【Conclusion】The lodging resistance of rice is a complex trait, and different germplasm resources have different lodging resistance characteristics. Scientific utilization of breeding resources is the key to rice lodging resistance breeding. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Partial cable-stayed bridges have the advantages of high rigidity, good economy and convenient construction. In recent years, they have been widely used in high-speed railway, but most of them are two-tower structures. In this paper, based on the main bridge of Ji'nan Yellow River Bridge on Zhengzhou-Ji'nan Railway, the structural system, side-to-middle span ratio and key parameters of beam-tower-cable are analyzed and studied for the long-span, five-tower, four-span and large-span partial cable-stayed bridge on high-speed railway. Through comprehensive comparison and study, the structure system of tower pier consolidation is selected for the Yellow River Bridge, which has the advantages of partial release of temperature force, bridge stiffness and track surface irregularity index to meet the requirements of ballastless track on high-speed railway. Vibration-reducing and isolation measures can be adopted for beam section, effectively reducing seismic force and improving overall economy of bridge. The main bridge uses a smaller ratio of mid-span at the edge to meet the requirement of no auxiliary span for flood control, and can effectively reduce the corner at the end of the beam, avoiding the increase of the investment of the whole bridge due to the use of large girder height. When the height of the tower is 38 m, the increase of the height of the tower can significantly reduce the internal force of the beam, but the deformation under temperature load will increase accordingly. Therefore, the selection of the height of the tower should take into account the structural forces and the requirements of track irregularity. AT - 61 cable is used. Increasing cable size has little effect on bridge rigidity, but it can significantly reduce beam bending moment, but increase beam irregularity and residual creep deformation. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to clarify the seismic mitigation and isolation performance of sliding friction pendulum bearings of long continuous prestressed concrete (PC) girder bridges in high seismic intensity areas, a nonlinear analysis model of space beam element of a long-unit PC continuous girder bridge with seismic fortification intensity of 9 degrees was established using CSiBridge software. Based on the seismic response of ordinary spherical steel bearing, the seismic isolation performance of lead rubber bearing and sliding friction pendulum bearing was compared and analyzed, and the friction coefficient and bearing curvature of sliding friction pendulum bearing were analyzed. The results show that, compared with the lead rubber bearing, the sliding friction pendulum bearing has better seismic isolation effect, less internal force and deformation of the fixed pier, and more uniform and reasonable force for the long-unit continuous girder bridge. For sliding friction pendulum bearings, the greater the friction coefficient, the greater the bending moment at the bottom of the fixed pier and the displacement at the top of the pier of the long continuous beam. The amplitudes of variation for friction coefficient, maximum bending moment at the bottom of the fixed pier, and the extreme displacement at the top of the pier were found to be 20%, 1.67%, and 1.45%, respectively. The radius of curvature of sliding friction pendulum bearing has little effect on the seismic isolation performance of the long continuous beam. The radius of curvature increases by 1.5 m, the maximum bending moment at the bottom of the fixed pier increases by 0.97%, and the displacement at the top of the fixed pier increases by 0. 37%-1.39%. [ABSTRACT FROM AUTHOR]

In order to explore the influence of different working conditions on the mechanical properties of dovetail joints, in this paper, the "Qing Dynasty Engineering Rules" of the Ministry of Qing Dynasty and "Wood Construction Technology of Ancient Chinese Buildings" were used as the weighing standards, using the results of wood properties tests conducted by other scholars as a reference, the numerical simulation of pseudo-static load was carried out on the dovetail joints of Qing Dynasty based on the finite element software ABAQUS. The influence of different angles outside the plane of tenon, different materials, different axial loads, and different load positions on the mechanical properties of dovetail tenon joints was investigated. The results showed that: 1) The hysteretic curves of dovetail mortise and tenon are all inverted z-shape. 2) The maximum bending moments at dovetail joints were 0.896, 0.914 kN·m and 0.979 kN·m when the lateral angles of the Fangs were 0°, 1.41° and 2.82°, respectively. When the axial load at the top of the column increases from 0 to 50 kN, the two-way maximum bending moments of dovetail joints change from 0.896 kN·m and 0.523 kN·m to 2.680 kN·m and 5.129 kN·m respectively. The two-way yield moment changed from 0.823 kN·m and 0.473 kN·m to 2.366 kN·m and 4.172 kN·m respectively. When the axial load at the top of the column increases from 50 kN to 100 kN, the changes of the two-way maximum bending moment and yield bending moment do not exceed 1%. 3) The peak viscous damping coefficients of dovetail joints corresponding to horizontal displacements of 0, 25 mm, and 50 mm applied on the beam side are 22.05%, 28.50%, and 29.38%, respectively. [ABSTRACT FROM AUTHOR]

[Objective] The pile-beam-arch (PBA) method, one among many metro construction techniques, is gradually gaining public favor owing to its unique advantages. These include superb structural stability and a remarkable effect on controlling surface settlement. At the same time, the side pile structure, a key mechanical component of the station, plays an important role in the success or failure of the projects involving PBA method. Most current research mainly focuses on the construction optimization and control countermeasures associated with the PBA method. However, there is a noticeable lack of studies focused on the mechanical behavior of side piles during construction and the principles governing side pile-soil interaction. [Methods] This paper focuses on a subway station project in the Guangzhou area, for which a simplified station model test method using the PBA method has been designed. Concurrently, this test method and numerical simulation have been employed to further investigate the evolution of the construction mechanics behavior of the side pile structure in different excavation processes of the station constructed using the PBA method. The primary focus of this study includes a comparative investigation into the soil pressure behind the piles and the internal force and deformation characteristics of the side piles under various spacing parameters. [Results] The results of this study are the following: 1) Under different pile spacing, stress concentration is most notable at the completion stage of the arch and the excavation stage of the first soil layer. As pile spacings increase, the stress concentration area behind the pile gradually shifts away from the pile position, with the stress peak decreasing correspondingly. 2) The bending moment of the side pile structure gradually increases throughout the construction process. The maximum section of the bending moment gradually migrates downward to the middle of the pile body, resulting in a "bow" distribution feature where the value is larger in the middle and smaller at both ends. Conversely, the axial force of the side pile structure remains relatively stable, presenting a "zigzag" pattern from the start to the end of the excavation. The maximum axial force appears at the junction between the side pile and the embedded stratum. 3) The peak value of the side pile's internal force increases with the pile spacings, and the pile spacings' influence on the side pile structure's axial force is more significant than its impact on the bending moment. As construction progresses, the lateral deformation of the pile body changes from initial "forward" deformation outside the station to final "bulging" deformation inside the station. The peak displacement of the pile body increases significantly with the pile spacing. 4) The stress and deformation of the side piles change most notably in the stage of excavation of the first soil layer. During actual construction, more attention should be paid to this stage, and appropriate lateral lining measures should be taken when necessary to maintain the stability of the station structure. [Conclusions] Through this experiment, the whole process of designing, making, operation testing, and data monitoring of the side pile structure in a metro station using the PBA method is demonstrated for students during the model test. This approach facilitates students' understanding of the mechanics and deformation evolution characteristics of a metro station constructed with the PBA method. [ABSTRACT FROM AUTHOR]

In order to study the influence of shape memory alloy (SMA) on the seismic response of railway self-centering piers, the SMA restrainer element is added to the verified two-spring model. Taking a railway bridge pier as the engineering background, the numerical analysis model is established based on OpenSees platform. By inputting three strong earthquake records, the influence of SMA restrainer on the pier is analyzed by nonlinear time history analysis method. The influence of the initial clearance and the change of the initial prestress of the key parameters of the SMA restrainer device on the displacement of the pier top and the bending moment of the pier bottom is discussed, and compared with the prestressed reinforcement restrainer. The results show that under ordinary ground motion El-Centro and Taft waves, the displacement at the top of the self-centering pier decreases with the decrease of the initial gap δ of the restrainer device, and the bending moment at the bottom of the pier increases with the decrease of the initial gap δ. With the increase of the initial preload of the SMA restrainer, the displacement of the top of the self-centering pier decreases and the bending moment of the bottom of the pier increases. The influence of SMA restrainer on the seismic response of self-centering piers under near-fault ground motion Northridge is complex. Under three strong earthquake records, compared with the prestressed reinforcement restrainer, SMA restrainer will reduce the bending moment of the pier bottom and increase the horizontal displacement of the pier top. [ABSTRACT FROM AUTHOR]

Based on the newly-built underpass tunnel of Nijiaqiao station in Chengdu Metro Line 8, which passes right under metro station of Line 1, and numerical simulation method is performed to compare and analyze the influence on the newly-built and existing structure between removing the temporary lining first and second lining first. Based on the working condition of "removal of temporary lining before the secondary liner", the plan of removing the support is further analyzed. Moreover, some results are verified by the on-site monitoring data. The main results show that: in the case of second lining first, the bending moment and settlement of the existing station and the preliminary lining bending moment and the secondary lining settlement of the new channel caused by the removal of the temporary lining are not obvious; for the case of temporary lining first, after all the temporary linings are removed at one time, the bending moments of existing and new structures change greatly along the section. In terms of structural settlement, the maximum sudden settlement of the preliminary lining of existing stations and new channels after the removal of temporary lining reaches 4.86 mm and 7.30 mm respectively. Basing on removing the temporary lining first, the most disadvantageous part occurs in the longitudinal middle of the underpass when the temporary lining is removed in sequence and removed by jumping. The settlement of the preliminary lining of the newly-built channel caused by the jumping is larger than that of the sequential dismantling, but its construction efficiency is higher. The specific method should be reasonably selected according to the construction safety standard and the economic requirements. [ABSTRACT FROM AUTHOR]

The multi span long continuous beam structure has problems such as high seismic force on fixed piers and difficulty in restoring ductile parts after earthquakes, making it difficult to design earthquake resistant structures in high-intensity seismic areas. In order to solve the seismic design problem of multi span long connected low tower cable-stayed bridges on high-speed railways, a span of (65.65 + 8 x 110 + 65.65) m single cable plane prestressed concrete low tower cable-stayed bridge was studied, and three different seismic system schemes, namely single fixed pier, rigid continuous beam, and friction pendulum bearing isolation, were analyzed and compared using nonlinear time history integration method. The research results indicate that the use of friction pendulum bearing isolation system has obvious advantages. Under design earthquake action, compared with a single fixed pier system, the transverse bending moment of the bridge pier is generally reduced by more than 70%, and the longitudinal bending moment of the fixed pier is reduced by about 80%. Further analysis of the parameters of the friction pendulum isolation support was conducted to determine appropriate support parameters, resulting in better support deformation and pier top shear force, with significant seismic reduction and isolation effects. The research conclusion is that in the case of small shear span ratio of bridge piers and high stiffness of the lower structure, the installation of friction pendulum isolation bearings can significantly reduce the seismic response of the lower structure during earthquakes, making each bridge pier uniformly stressed. At the same time, reasonable bearing design can meet the needs of large earthquake displacement and have sufficient self resetting ability. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transportation Science & Technolgy is the property of Transportation Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transportation Science & Technolgy is the property of Transportation Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Civil Engineering & Architecture is the property of Journal of Beijing University of Civil Engineering & Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Civil Engineering & Architecture is the property of Journal of Beijing University of Civil Engineering & Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To reduce the mass of mechanical elastic wheels, the lightweight analysis was conducted by the finite element analysis software of Abaqus. Considering the bending moment load and radial load conditions of the wheels at all times, the finite element model of mechanical elastic wheels was established, and the finite element simulation analysis was carried out. The force data of the nodes were extracted from the simulation results to determine the load of wheel hub and hinge group. The weighted variable density method was used to optimize the topology of the hub and hinge group of mechanical elastic wheel, and the 3D model was reconstructed after optimization. The results show that the mass values of the optimized mechanical elastic wheel, wheel hub and hinge assembly are reduced by 15.1%, 27.9% and 22.6%, respectively. [ABSTRACT FROM AUTHOR]

During the construction of the Nansha-Zhuhai-Zhongshan Intercity Railway in the Greater Bay Area, in order to meet the requirements including platform yield distance, platform floor layout in the public area of the Qijiangxincheng station, and optimize the station scale and spatial visual effect, the public area was designed without columns. At present, the engineering experience of adopting the concept of no column in the underground structure of intercity railway is insufficient. The span of the station on the third underground floor is 22.9 m, which leads to questions including component stress design, section selection, anti-floating design, etc. Based on the scheme design of the project, this paper used the numerical simulation method to analyze the design scheme under various working conditions by comparing the stress results of the bottom uplift pile setting and the roof structure. The results show that: The bending moment at the midspan and bearing decreases by 67.5% and 69.4% respectively after the bottom plate is set with double rows of uplift piles. The bending moment of the bottom plate only increases 4.2%, and the scheme has more advantages in terms of construction and economy. In the section type of roof camber, the bending moment of roof midspan can be reduced by 63.85%, and the bending moment of support can be reduced by 51%, which can significantly improve the structural stress. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Lodging is a bottleneck problem of restricting the high quality and high yield of rice (Oryza sativa L.) under the rice-crayfish coculture. To study the effect of exogenous melatonin spraying on the lodging characteristics of rice stems under rice-crayfish coculture, 'Nanjing 5718' was as the experimental material, and the experiment set two treatments: 200 μmolµL-1 melatonin foliar-spraying at the early stage of jointing (MT) and control treatment (CK) . The morphology index, culm mechanics index, culm chemical composition content, rice yield and the expression levels of key genes for lignin and cellulose biosynthesis under different treatments were determined. The results showed that the rice yield of MT treatment was 9 261 kgµhm-2, which had no significant difference with CK treatment, however, the spikelets per panicle of MT treatment significantly increased than that of CK, while the effective panicles and seed setting rate significantly decreased. Compared with CK treatment, the plant height, panicle length and gravity center height of MT treatment significantly decreased by 13.04%, 14.91% and 22.93%, respectively. The flexural resistance and breaking strength of the second internode significantly increased by 22.39% and 22.34%, and bending moment and lodging index significantly decreased by 20.61% and 35.03%. And the expression levels of key genes for lignin and cellulose biosynthesis including OsCoMT, OsCesA4, OsCesA7 and OsCesA9 genes were upregulated under MT treatment. Correlation analysis showed that the lodging index of MT treatment was extremely significantly positively correlated with plant height, panicle length, and length from breaking point to panicle top, and was significantly negatively correlated with flexural resistance, breaking strength, and bending stress. In conclusion, spraying melatonin could improve the lodging resistance of rice stem under the premise of stable rice production in the rice-crayfish coculture mode, which provided theoretical and practical guidance for the regulation of rice lodging resistance under the rice-crayfish coculture mode. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the applicability of assembled piers in high-speed railway bridges, the assembled piers in Guba Bridge of Beijing-Xiong'an High-speed Railway are taken as the prototype, and finite element numerical simulation is carried out with ANSYS software on the basis of full-scale quasi-static test, and the results are compared with the experimental data. The verified finite element model is used to analyze the seismic performance of the actual assembled bridge pier and the time-history response of a two-span continuous beam bridge with assembled bridge pier under seismic waves. The research shows that the hysteretic curves, skeleton curves, stiffness degradation characteristics, energy dissipation capacity and residual deformation of both the test assembly pier and the actual bridge assembly pier are basically the same and are not significantly different from those of the cast-in-situ pier, indicating that the sleeve connection does not have significant impact on the hysteretic performance and restoring force characteristics of the pier. Considering the pile-soil effect, the hysteretic area of the assembly pier decreases, the initial stiffness and hysteretic energy consumption decrease by 36% and 23.5% respectively. The natural frequency of the continuous beam bridge with assembled piers under the same mode is slightly smaller than that with cast-in-situ piers, and the maximum difference is only 2.7%, while the natural frequency is reduced by as much as 19% due to the pile-soil effect. Under the action of the actual seismic wave, the maximum displacement of the pier top, the bending moment and shear force of the pier bottom along the bridge direction of the assembled pier continuous beam bridge are close to those of the cast-in-situ pier. However, the pile-soil effect increases the maximum displacement of the pier top along the bridge direction by 9.4%, and decreases the bending moment and shear force of the pier bottom along the bridge direction by 41% and 40.9%, respectively. The results show that the seismic performance of high-speed railway bridge with assembled piers is not significantly reduced compared with that of cast-in-place pier bridge. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Under strong winds, newly transplanted trees can tilt or fall, causing economic losses and injuries. Therefore, studying the wind resistance of trees and methods to enhance their wind resistance is of great significance. In this study, 3D simplified models of spruce were built before and after the installation of support frames in them. The trees were 8 m in height, 4 m in crown diameter, with a trunk diameter of 0.3 m at the base. Corresponding mechanical properties were assigned to the models and fluid-solid interaction was numerically simulated. The results showed that without support, the displacement of the spruce treetop, shear stress on branches, and bending moment at the base increased with increasing wind speed. At a wind speed of 20 m.s-1, the maximum shear stress in the transverse direction of spruce was 2.6 MPa, exceeding 85% of its transverse shear strength. This indicates that there is a possibility of shear failure in the tree with the failure point at the junction of the primary branch and the main stem. Supporting the tree at 1/8, 2/8, and 3/8 of its height reduced the displacement of the treetop, shear stress on branches, and bending moment at the base, ultimately lowering the risk of shear failure and falling. When the support frame was placed at 2/8 of the tree's height, the shear stress on the tree was minimized, reducing the risk of branch breakage by 50%. However, the part of the tree above the support frame had an increased wind-induced oscillation frequency compared to the unsupported tree, reducing the tree's stability and increasing the risk of branch breakage owing to prolonged high-frequency vibration. Numerical simulation of wind-induced tree response is highly customizable, and its results have reference value for studying wind resistance of trees and designing support frames for trees. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)