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In order to solve the demand for damage assessment of a large number of reinforced concrete (RC) frame communication buildings after earthquakes, this paper studied the damage assessment methods from the component level to the overall structure based on convolutional neural networks (CNN). Firstly, a large number of damage survey pictures of RC frame structures after earthquakes such as the Wenchuan earthquake, Ludian earthquake, and Lushan earthquake were screened and processed, and a damage assessment dataset of RC frame beams and columns was established. Secondly, a damage assessment method for RC frames based on CNN was established through the study of 3 key issues: The task of detecting and recognizing the components of beams and columns from the photos of structural damage was completed by training and establishing the YOLOv5 network model; the detection performance of the YOLOv5 network model was improved and optimized; 3 network models (ResNet50, MobileNet V2, and AlexNet model) were selected and compared for the accuracy of damage level assessment of beams and columns. Finally, a damage assessment model of beams and columns based on ResNet50 was established. The method of determining the damage level from the component level to the overall structure was given, and the availability of the method in the paper was verified by damage assessment of an actual damaged frame, and the results show that the method in the paper has high consistency with the damage assessment conclusion of experts, and the optimized CNN model has good accuracy and stability, and has good applicability to the damage assessment of post-earthquake RC frame structures. [ABSTRACT FROM AUTHOR]

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers 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 Automobile Technology is the property of Automobile 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 Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department 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.)

Compared with conventional frame structures, self-centering frame structures exhibit less severe plastic deformation after earthquakes. However,there is limited research on the low-damage infill wall compatible with self-centering frames,which hinders the extensive application of the self-centering structures. This paper designed two types of low-damage infill wall for a self-centering RC frame and a series of shaking table tests, in order to compare and analyze the seismic performance of these two types of infill walls in the given self-centering frame. According to the experiment results, suggestions are then proposed to utilize the low-damage infill walls in self-centering structures. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute 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.)

Shape memory alloy pseudo-rubber (SMAPR) is a new kind of porous damping material for isolation and vibration mitigation, with complicated internal structures. In this study, a theoretical model of SMAPR was proposed through layer decomposition according to its micro-structure and fabrication process, as well as the nonlinear stiffness characteristics. First, a contacted micro-curved-beam (CMCB) was built and the relationship between the model parameters and physical quantities of SMAPR was obtained. Then the stiffness equation was derived. Based on the analysis of the non-linear stiffness of SMAPR, the relationship between the quantity of contact points and the compression strain increment was obtained for both of loading and unloading process. Subsequently, the layer constitutive model of SMAPR was proposed and verified. A parametric analysis was conducted to investigate the effects of nominal densities, diameters of SMA wires and coefficient of friction on the behavior of SMAPR. Results show that the proposed model is closer to the real state of SMAPR, and could reflect both of the influence of micro-parameters of SMAPR and fabrication process on the macro-properties. Parametric analysis shows that the elastic modulus of SMAPR increases with the increment of nominal density, diameter of SMA wires and coefficient of friction. [ABSTRACT FROM AUTHOR]