Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654544
Q. Gao, Hongwei Wang, Z. Wan, Hongwei Liu, Risheng Huang, Haonan Wang
In this paper, a high fill soft foundation slope is taken as an example to analyze its stability by FLAC3D. The secondary slip surface of the slope is obtained, and the safety factor is 0.19. The main slip surface of the slope is obtained after the subgrade is converted into the applied load, and the safety factor is 0.61. The two are different because the safety factor is aimed at different objects, the former is the construction of high fill roadbed, the latter is the whole original slope. The length of the anti-slide pile is set as 16m, 17m, 18m, 19m and 20m. After calculation, it is found that the safety factor increases with the increase of the pile length, and the maximum shear force and maximum horizontal displacement of anti-slide pile both decrease with the increase of the pile length, and the change tends to be gentle when the pile length increases to 18m. Therefore, a pile length of 20m is chosen. A total of 16 anti-slide pile layout modes are set with longitudinal/transverse spacing of 5m, 10m, 15m and 20m, respectively.
{"title":"Research on Stability Analysis of Soft Foundation Slope and its Anti-Slip Pile Support Technology","authors":"Q. Gao, Hongwei Wang, Z. Wan, Hongwei Liu, Risheng Huang, Haonan Wang","doi":"10.1109/ISTTCA53489.2021.9654544","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654544","url":null,"abstract":"In this paper, a high fill soft foundation slope is taken as an example to analyze its stability by FLAC3D. The secondary slip surface of the slope is obtained, and the safety factor is 0.19. The main slip surface of the slope is obtained after the subgrade is converted into the applied load, and the safety factor is 0.61. The two are different because the safety factor is aimed at different objects, the former is the construction of high fill roadbed, the latter is the whole original slope. The length of the anti-slide pile is set as 16m, 17m, 18m, 19m and 20m. After calculation, it is found that the safety factor increases with the increase of the pile length, and the maximum shear force and maximum horizontal displacement of anti-slide pile both decrease with the increase of the pile length, and the change tends to be gentle when the pile length increases to 18m. Therefore, a pile length of 20m is chosen. A total of 16 anti-slide pile layout modes are set with longitudinal/transverse spacing of 5m, 10m, 15m and 20m, respectively.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134382355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654604
Hongyu Fu, Yaoliang Huang, Weifeng Li
With the development of autonomous vehicles and unmanned aerial vehicles, unmanned ships have also become a hot topic. In order to solve the problem of real-time motion attitude estimation of the ship itself when berthing and sailing relying on data driven. Based on the monocular camera, the improved ORB (Oriented FAST and Rotated Brief) enhanced SLAM (Simulation Localization and Mapping) algorithm image feature extraction method is used to solve the monocular camera motion pose, and finally build the ship motion control model. Solve the problem of ship berthing process control. This article uses the monocular camera video data when berthing to verify. The results show that compared with the traditional SLAM algorithm, the algorithm requires less calculation time and higher perception accuracy during the berthing process of the ship.
随着自动驾驶汽车和无人机的发展，无人船也成为热门话题。为了解决船舶在靠泊和航行时依赖数据驱动的自身实时运动姿态估计问题。基于单目摄像机，采用改进的ORB (Oriented FAST and rotational Brief)增强SLAM (Simulation Localization and Mapping)算法图像特征提取方法求解单目摄像机的运动姿态，最终建立舰船运动控制模型。解决船舶靠泊过程控制问题。本文采用单目摄像机停泊时的视频数据进行验证。结果表明，与传统SLAM算法相比，该算法在船舶靠泊过程中计算时间更短，感知精度更高。
{"title":"Ship berthing motion control based on improved Simulation Localization and Mapping algorithm","authors":"Hongyu Fu, Yaoliang Huang, Weifeng Li","doi":"10.1109/ISTTCA53489.2021.9654604","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654604","url":null,"abstract":"With the development of autonomous vehicles and unmanned aerial vehicles, unmanned ships have also become a hot topic. In order to solve the problem of real-time motion attitude estimation of the ship itself when berthing and sailing relying on data driven. Based on the monocular camera, the improved ORB (Oriented FAST and Rotated Brief) enhanced SLAM (Simulation Localization and Mapping) algorithm image feature extraction method is used to solve the monocular camera motion pose, and finally build the ship motion control model. Solve the problem of ship berthing process control. This article uses the monocular camera video data when berthing to verify. The results show that compared with the traditional SLAM algorithm, the algorithm requires less calculation time and higher perception accuracy during the berthing process of the ship.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131643455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654637
A. Zheng, Jiahuan Xu, Panpan Song
Plastic drainage boards are widely used as the most common drainage material in soft foundation reinforcement. The quality of plastic drainage boards directly affects the effect of soft foundation reinforcement. In order to study the influence of temperature and relative humidity on the test of plastic drainage board, the effects of state adjustment and ambient temperature and humidity on the test results were studied by using the method of mathematical statistics. By changing the temperature and humidity in the general indoor temperature and humidity range, and ensuring that the temperature and humidity in the test is consistent with the state adjustment, the plastic drainage board was tested, and the characteristics of data discreteness and the variation of numerical value with temperature and humidity were obtained through statistical analysis. The results show that temperature and humidity have little effect on the width of plastic drainage plate, but have an influence on the numerical size and discreteness of tensile strength and elongation test results. At $180^{circ}mathbf{C}$, the tensile strength and elongation of plastic drainage plate complex and the elongation of membrane have great data dispersion.
{"title":"Statistical Analysis of Influence of Temperature and Humidity on the Test Results of Plastic Drainage Board","authors":"A. Zheng, Jiahuan Xu, Panpan Song","doi":"10.1109/ISTTCA53489.2021.9654637","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654637","url":null,"abstract":"Plastic drainage boards are widely used as the most common drainage material in soft foundation reinforcement. The quality of plastic drainage boards directly affects the effect of soft foundation reinforcement. In order to study the influence of temperature and relative humidity on the test of plastic drainage board, the effects of state adjustment and ambient temperature and humidity on the test results were studied by using the method of mathematical statistics. By changing the temperature and humidity in the general indoor temperature and humidity range, and ensuring that the temperature and humidity in the test is consistent with the state adjustment, the plastic drainage board was tested, and the characteristics of data discreteness and the variation of numerical value with temperature and humidity were obtained through statistical analysis. The results show that temperature and humidity have little effect on the width of plastic drainage plate, but have an influence on the numerical size and discreteness of tensile strength and elongation test results. At $180^{circ}mathbf{C}$, the tensile strength and elongation of plastic drainage plate complex and the elongation of membrane have great data dispersion.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131197229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654501
X. Luo, Qiliang Sang, W. Long, Jian-zhong He, Bo Jiang
To systematically study the impact of deep foundation pit excavation on adjacent existing rail structure and electric tower, we can take targeted deformation control measures and ensure the safety of the surrounding environment. Based on the engineering examples and considering the double hardening characteristics of soil, a three-dimensional fine-grained dynamic and static model of foundation pit + roadbed + viaduct + pylon was built to analyze the influence of foundation pit excavation on the track and the high-voltage tower and put forward targeted deformation control measures. Finally, a comparative analysis and demonstration were conducted with the monitoring results of the whole process of on-site construction. Many useful conclusions have been drawn. The study can provide guidance for the design and construction of this project, and also provide a reference for similar projects.
{"title":"Research on Impact of Deep Foundation Pit on Adjacent Rail Transit in Sensitive Environment","authors":"X. Luo, Qiliang Sang, W. Long, Jian-zhong He, Bo Jiang","doi":"10.1109/ISTTCA53489.2021.9654501","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654501","url":null,"abstract":"To systematically study the impact of deep foundation pit excavation on adjacent existing rail structure and electric tower, we can take targeted deformation control measures and ensure the safety of the surrounding environment. Based on the engineering examples and considering the double hardening characteristics of soil, a three-dimensional fine-grained dynamic and static model of foundation pit + roadbed + viaduct + pylon was built to analyze the influence of foundation pit excavation on the track and the high-voltage tower and put forward targeted deformation control measures. Finally, a comparative analysis and demonstration were conducted with the monitoring results of the whole process of on-site construction. Many useful conclusions have been drawn. The study can provide guidance for the design and construction of this project, and also provide a reference for similar projects.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131314050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654447
Lei Wang, Ting Wang, Wei Chen, Yunfei Li
With the development of the rock mass joints and the increase in the excavation depth of the slope, the failure of the anti-dipping rock slope has occurred from time to time, which has attracted the attention of scholars. Taking a proposed highway cutting slope as the research object, establish a finite element model for the excavation of a high anti-dipping rock slope. The strength reduction method is used to calculate the safety factor of the slope, stability and excavation response are also analyzed. The results show that the horizontal displacement of the rock mass caused by excavation is small, the vertical displacement is mainly concentrated near the excavation area of the slope, and the upward unloading rebound is mainly; As the excavation progresses, the maximum shear strain develops from the silty clay and strongly weathered sandy mudstone in the shallow ground to the slope toe. In the actual construction process, it is recommended to pay attention to the failure of the rock mass at the step slope toe. The safety factor of the slope gradually decreases as the excavation progresses. When the first-level slope is excavated, it is still in a stable state. The research results can provide a reference for anti-dipping slopes with similar characteristics.
{"title":"Numerical simulation analysis of excavation response of counter-tilt rock slope","authors":"Lei Wang, Ting Wang, Wei Chen, Yunfei Li","doi":"10.1109/ISTTCA53489.2021.9654447","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654447","url":null,"abstract":"With the development of the rock mass joints and the increase in the excavation depth of the slope, the failure of the anti-dipping rock slope has occurred from time to time, which has attracted the attention of scholars. Taking a proposed highway cutting slope as the research object, establish a finite element model for the excavation of a high anti-dipping rock slope. The strength reduction method is used to calculate the safety factor of the slope, stability and excavation response are also analyzed. The results show that the horizontal displacement of the rock mass caused by excavation is small, the vertical displacement is mainly concentrated near the excavation area of the slope, and the upward unloading rebound is mainly; As the excavation progresses, the maximum shear strain develops from the silty clay and strongly weathered sandy mudstone in the shallow ground to the slope toe. In the actual construction process, it is recommended to pay attention to the failure of the rock mass at the step slope toe. The safety factor of the slope gradually decreases as the excavation progresses. When the first-level slope is excavated, it is still in a stable state. The research results can provide a reference for anti-dipping slopes with similar characteristics.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115530534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654795
Jichao Xie, Peng Liu
The design process in the foundation pit engineering exist many uncertain factors including soil parameters, soil thickness, load and groundwater depth and so on. So the calculated displacement, settlement and safety coefficient are random and uncertain. This paper puts forward a kind of reliability analysis method of foundation pit engineering based on support vector machine (SVM). Firstly, the distributions of the random parameters are determined. The uniform test is used for obtaining random parameter samples. The random parameter samples are calculated to get the corresponding response sample, such as the maximum horizontal displacement, maximum ground settlement and safety factors. Then, the SVM is adopted to establish the response surfaces between the random samples and corresponding response parameters. On the basis of the response surfaces, the random parameters generated by the Latin hypercube sampling method are predicted to obtain the probability density distribution of each response parameter. Finally, the system failure probability of foundation pit engineering is calculated. The case study shows that the method has high computing efficiency and the result is reasonable. It provides the basis for analyzing the reliability of foundation pit engineering.
{"title":"Reliability analysis of foundation pit engineering using support vector machine","authors":"Jichao Xie, Peng Liu","doi":"10.1109/ISTTCA53489.2021.9654795","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654795","url":null,"abstract":"The design process in the foundation pit engineering exist many uncertain factors including soil parameters, soil thickness, load and groundwater depth and so on. So the calculated displacement, settlement and safety coefficient are random and uncertain. This paper puts forward a kind of reliability analysis method of foundation pit engineering based on support vector machine (SVM). Firstly, the distributions of the random parameters are determined. The uniform test is used for obtaining random parameter samples. The random parameter samples are calculated to get the corresponding response sample, such as the maximum horizontal displacement, maximum ground settlement and safety factors. Then, the SVM is adopted to establish the response surfaces between the random samples and corresponding response parameters. On the basis of the response surfaces, the random parameters generated by the Latin hypercube sampling method are predicted to obtain the probability density distribution of each response parameter. Finally, the system failure probability of foundation pit engineering is calculated. The case study shows that the method has high computing efficiency and the result is reasonable. It provides the basis for analyzing the reliability of foundation pit engineering.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115811977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654435
Xiangyu Li
In order to study the optimized influence of different pasting methods of CFRP on bridges, the ABAQUS finite element software was proposed, and combined with the structural form of Guangxi Nadezhong Bridge, the influence laws of CFRP pasting directions and CFRP pasting layers on the stress and deflection of bridges were discussed comprehensively. The results showed that the CFRP adhesion effectively reduced the structure stress, span deflection and cracking loads. And increasing pasting angle would decrease the reinforcement efficiency of CFRP, among which the pasting angles of 0° and 90° achieved the best reinforcement effect, reducing the structural stress and mid-span deflection by 17.6% and 17.30%, respectively, and increasing the cracking and flexural load by 3.5% and 5.3%, respectively. A larger number of CFRP layers would lead to gradual reduction of stress and mid-span deflection, and increasing cracking load. Accordingly, longitudinal and transverse CFRP application method and increasing the number of longitudinal CFRP fabric layers were recommended to optimize the bridge bearing structure.
{"title":"Finite Element Optimization Analysis of CFRP Reinforced Box Girder Bridge Under Traffic Load","authors":"Xiangyu Li","doi":"10.1109/ISTTCA53489.2021.9654435","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654435","url":null,"abstract":"In order to study the optimized influence of different pasting methods of CFRP on bridges, the ABAQUS finite element software was proposed, and combined with the structural form of Guangxi Nadezhong Bridge, the influence laws of CFRP pasting directions and CFRP pasting layers on the stress and deflection of bridges were discussed comprehensively. The results showed that the CFRP adhesion effectively reduced the structure stress, span deflection and cracking loads. And increasing pasting angle would decrease the reinforcement efficiency of CFRP, among which the pasting angles of 0° and 90° achieved the best reinforcement effect, reducing the structural stress and mid-span deflection by 17.6% and 17.30%, respectively, and increasing the cracking and flexural load by 3.5% and 5.3%, respectively. A larger number of CFRP layers would lead to gradual reduction of stress and mid-span deflection, and increasing cracking load. Accordingly, longitudinal and transverse CFRP application method and increasing the number of longitudinal CFRP fabric layers were recommended to optimize the bridge bearing structure.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"3461 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124120938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654526
Liang Tang, Jin-liang Li, Yonglan Xie, Zhen Tian
Passive energy dissipation systems have been in development for several decades for enhancing the seismic performance of structures. Viscous fluid dampers are hydraulic devices that dissipate energy when stroked. They convert the kinetic energy of the structure's motion into heat. Viscous fluid dampers are applied as a kind of passive energy dissipation device for enhancing seismic resistance of structures. As a method of absorbing seismic energy, viscous dampers provide an alternative way for yielding or failure of structures. Because almost all the seismic energy can be dissipated by viscous dampers, the structure can be undamaged and ready for use immediately after an earthquake. In this study, full-scale experiments were conducted to investigate the dynamic characters of viscous fluid dampers. The experimental results show that the mechanical properties of the damper are stable and meet the expected design standards. The hysteresis loops approach a rectangular shape under steady-state harmonic motion, which means the tested damper has a strong energy dissipation capacity.
{"title":"Experimental Research on Dynamic Performance of Viscous Fluid Damper","authors":"Liang Tang, Jin-liang Li, Yonglan Xie, Zhen Tian","doi":"10.1109/ISTTCA53489.2021.9654526","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654526","url":null,"abstract":"Passive energy dissipation systems have been in development for several decades for enhancing the seismic performance of structures. Viscous fluid dampers are hydraulic devices that dissipate energy when stroked. They convert the kinetic energy of the structure's motion into heat. Viscous fluid dampers are applied as a kind of passive energy dissipation device for enhancing seismic resistance of structures. As a method of absorbing seismic energy, viscous dampers provide an alternative way for yielding or failure of structures. Because almost all the seismic energy can be dissipated by viscous dampers, the structure can be undamaged and ready for use immediately after an earthquake. In this study, full-scale experiments were conducted to investigate the dynamic characters of viscous fluid dampers. The experimental results show that the mechanical properties of the damper are stable and meet the expected design standards. The hysteresis loops approach a rectangular shape under steady-state harmonic motion, which means the tested damper has a strong energy dissipation capacity.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114545082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654720
Pengxu Li, J. Xia, Wenting Zhao
Aiming at the typical high temperature sulfate environment in underground engineering, the degradation mechanism of the new grouting material under the coupling action of heat damage and sulfate erosion was studied. Forty-four groups of specimens with different water-binder ratios were prepared. The changes of appearance, mass, compressive strength and sulfate ion content of the specimens under the action of different temperature (20°C, 30°C, 60°C, 90°C) and different sulfate concentration (0, 5%, 10%) were detected, the microstructure was observed by electron microscope (SEM), the content model of sulfate ion was established. The results show that: in the environment of sulfate erosion, high temperature has a significant effect on the deterioration of new grouting materials, the higher the temperature, the more obvious the deterioration. With the increase of water-binder ratio, the deterioration of new grouting materials becomes more and more serious. At the early stage of erosion, ettringite and other materials are gradually formed and continuously filled with pores and microcracks. At the later stage of erosion, the expansion stress of ettringite and the crystallization pressure of sulfate make the material gradually expand and destroy. The model of sulfate ion content established is in good agreement with the experimental results.
{"title":"Deterioration Mechanism of New Grouting Materials Under Coupling Effect of Heat Damage and Sulfate Attack","authors":"Pengxu Li, J. Xia, Wenting Zhao","doi":"10.1109/ISTTCA53489.2021.9654720","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654720","url":null,"abstract":"Aiming at the typical high temperature sulfate environment in underground engineering, the degradation mechanism of the new grouting material under the coupling action of heat damage and sulfate erosion was studied. Forty-four groups of specimens with different water-binder ratios were prepared. The changes of appearance, mass, compressive strength and sulfate ion content of the specimens under the action of different temperature (20°C, 30°C, 60°C, 90°C) and different sulfate concentration (0, 5%, 10%) were detected, the microstructure was observed by electron microscope (SEM), the content model of sulfate ion was established. The results show that: in the environment of sulfate erosion, high temperature has a significant effect on the deterioration of new grouting materials, the higher the temperature, the more obvious the deterioration. With the increase of water-binder ratio, the deterioration of new grouting materials becomes more and more serious. At the early stage of erosion, ettringite and other materials are gradually formed and continuously filled with pores and microcracks. At the later stage of erosion, the expansion stress of ettringite and the crystallization pressure of sulfate make the material gradually expand and destroy. The model of sulfate ion content established is in good agreement with the experimental results.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114960081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-12DOI: 10.1109/ISTTCA53489.2021.9654611
Shuangchang Feng, Jie Chen, Y. Liang, Chen Wang
As an important parameter of elevator, elevator balance coefficient directly affects the safety and comfort performance of traction driven elevator. According to the requirements of GBT 10059–2009, the balance coefficient of traction driven elevator shall be in the range of 0.4-0.5. After the installation of the elevator, the balance coefficient will be tested. If the number of counterweights is not increased or reduced for a long time, the balance coefficient of the elevator will not change significantly. The current inspection specification TSG T7001-2009 stipulates that the balance coefficient test method is mainly through the current load curve method. This method needs to carry the weight repeatedly, measure the change of motor current, and obtain the specific value of balance coefficient by fitting the current and load curve. However, this method has high labor intensity and long operation time, requires frequent handling of weights and high labor intensity for operators. Therefore, this paper designs an auxiliary test device for elevator balance coefficient, which can solve the technical problem of moving weights frequently.
{"title":"Research on Auxiliary Test Device for Elevator Balance Coefficient","authors":"Shuangchang Feng, Jie Chen, Y. Liang, Chen Wang","doi":"10.1109/ISTTCA53489.2021.9654611","DOIUrl":"https://doi.org/10.1109/ISTTCA53489.2021.9654611","url":null,"abstract":"As an important parameter of elevator, elevator balance coefficient directly affects the safety and comfort performance of traction driven elevator. According to the requirements of GBT 10059–2009, the balance coefficient of traction driven elevator shall be in the range of 0.4-0.5. After the installation of the elevator, the balance coefficient will be tested. If the number of counterweights is not increased or reduced for a long time, the balance coefficient of the elevator will not change significantly. The current inspection specification TSG T7001-2009 stipulates that the balance coefficient test method is mainly through the current load curve method. This method needs to carry the weight repeatedly, measure the change of motor current, and obtain the specific value of balance coefficient by fitting the current and load curve. However, this method has high labor intensity and long operation time, requires frequent handling of weights and high labor intensity for operators. Therefore, this paper designs an auxiliary test device for elevator balance coefficient, which can solve the technical problem of moving weights frequently.","PeriodicalId":383266,"journal":{"name":"2021 4th International Symposium on Traffic Transportation and Civil Architecture (ISTTCA)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116177229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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