检索结果-内蒙古大学图书馆

Mechanical and Thermal Properties of Environmentally Friendly Straw Boards

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Zheng, Chaorong Sun, Kuo Chen, Yixiao Zhang, Wenyuan Wu, Yue School of Civil Engineering Harbin Institute of Technology Harbin150090 China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin150090 China

Straw is an environmentally friendly, cost-effective, and abundant raw material for building boards. To assess the feasibility of using straw boards as alternative sheathing panels in light-steel-members such as walls and floors, the mechanical and thermal properties of straw boards with high densities were investigated. The straw boards involved in this study include five wheat straw strand boards (WSSB12, WSSB15, WSSB18, WSSB25, and WSSB30) and a paper straw board (PSB58). Mechanical properties, including compression, tension, and bending properties, were investigated by tests and a proposed prediction method of tensile strength. In the experimental studies of compression properties, the failure modes and characteristics of load-deformation curves of compressive specimens, and the parameters of compression properties, including the strength, elastic modulus, and Poisson ratio, were analyzed and summarized, and the differences in material directivity were discussed as well. The WSSBs were found to be transverse isotropic material with brittle characteristics in the plane, while the PSB showed similar brittle characteristics in the failure stage. Furthermore, the experimental studies of bending properties and similar analyses and summaries for test results were carried out. Results show that the bending strength is less than the compressive strength for WSSBs, while the case is just the opposite for PSB, and the elastic moduli of bending and compression are close for both WSSBs and PSB. Then, finite element models (FEMs) of the bending test specimens using the user material subroutine UMAT were developed to predict the tensile strength ft, and the prediction results were qualitatively assessed based on the correlation between ft and fb, fc. As verified, the prediction results of ft are believable, and the prediction method proposed in this study is feasible. Such a prediction method could efficiently determine the tensile strength of similar brittle materials withou

关键词： Tensile strength

Damage evaluation method for high-speed railway girder based on ultra-weak fiber Bragg grating sensing technology 8

学校读者我要写书评

暂无评论

Damage evaluation method for high-speed railway girder based...

8th Symposium on Novel Photoelectronic Detection Technology and Applications

作者： Liu, Weikang Zhang, Xiulin Zhou, Wensong Key Lab of Structures Dynamic Behavior and Control The Ministry of Education Harbin Institute of Technology Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters The Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China School of Civil Engineering Harbin Institute of Technology Heilongjiang Harbin150090 China

ISBN: (数字)9781510653122

ISBN: (纸本)9781510653115

Ultra-weak fiber Bragg grating (UWFBG) sensing technology has considerable multiplexing capacity on one fiber. Therefore, UWFBG have the potential of distributed monitoring, and its monitoring accuracy is higher than that of distributed optical fiber sensing technology. In this work, a novel deformation monitoring method based on UWFBG for high-speed railway girders was proposed, and the deformation of a real high-speed railway girder was monitored by UWFBG. In the test, an UWFBG array was pasted on the bottom of a real high-speed railway beam by epoxy resin, and a vibrating wire strain gauge was pasted in the middle of the span for comparison. The beam was loaded step by step through a reaction frame. During the loading process, the deformation of the beam at different positions was recorded by the UWFBG array. The results show that this method can effectively monitor the deformation of high-speed railway girder, and provide safety guarantee for the normal operation of high-speed railway. © 2022 SPIE

关键词： Deformation

Distributed real-time in-situ monitoring method for deformation measurement of landslide 8

学校读者我要写书评

暂无评论

Distributed real-time in-situ monitoring method for deformat...

8th Symposium on Novel Photoelectronic Detection Technology and Applications

作者： Liu, Weikang Zhou, Wensong Key Lab of Structures Dynamic Behavior and Control The Ministry of Education Harbin Institute of Technology Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters The Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China School of Civil Engineering Harbin Institute of Technology Heilongjiang Harbin150090 China

ISBN: (数字)9781510653122

ISBN: (纸本)9781510653115

Landslide disasters often cause huge property losses and casualties. Therefore, distributed real-time landslide deformation monitoring is of great significance to ensure the safety of people's lives and property, and the stability evaluation of landslide. Ultra-weak fiber Bragg grating (UWFBG) sensing technology can realize the measurement distance of 20 km for single optical fiber, and the single measurement time is less than 1 s. Therefore, it has the potential of distributed real-time monitoring. In this work, a novel distributed real-time landslide deformation monitoring method based on UWFBG was proposed. And this method was applied to a real landslide in Yibin City, Sichuan Province, China, to monitor its deformation in situ. The feasibility of the monitoring method was verified and the landslide deformation was analyzed. The in-situ monitoring results show that on the time scale, the local deformation of the landslide is gradually increasing;on the spatial scale, there are some points with large local deformation, but the overall deformation in the monitoring area is small. The monitored results also suggest that the landslide is in a stable state during the monitoring period. © 2022 SPIE

关键词： Landslides

Real-time monitoring of soil moisture field using ultra-weak fiber Bragg gratings 8

学校读者我要写书评

暂无评论

Real-time monitoring of soil moisture field using ultra-weak...

8th Symposium on Novel Photoelectronic Detection Technology and Applications

作者： Liu, Weikang Zhou, Wensong Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China School of Civil Engineering Harbin Institute of Technology Heilongjiang Harbin150090 China

ISBN: (数字)9781510653122

ISBN: (纸本)9781510653115

Soil moisture field has an obvious influence on the stability of reservoir bank slope. Thus, effective, real-time, reliable, and high precision monitoring methods are imperative. However, the existing soil moisture monitoring methods have more or less deficiencies. In this paper, a novel soil moisture monitoring and estimation method based on an ultra-weak fiber Bragg grating (UWFBG) array is proposed which is suitable for large-scale in-situ monitoring. A soil moisture monitoring device is designed and fabricated. This monitoring device consists of several monitoring units, and each monitoring unit consists of a soil container, protector and two UWFBG. laboratory calibration tests were conducted to establish a relationship between wavelength change and soil moisture content. The test results show that the monitoring accuracy of the device is related to the quality of the loaded dry soil. When the mass of dry soil is 100 g, the monitoring accuracy of soil moisture content is 1.68 % (mass ratio). © 2022 SPIE

关键词： Soil moisture

Pipeline Leakage Localization Using Internally Installed Distributed Fiber Optic Sensors 8

学校读者我要写书评

暂无评论

Pipeline Leakage Localization Using Internally Installed Dis...

8th Symposium on Novel Photoelectronic Detection Technology and Applications

作者： Liu, Weikang Zhou, Wensong Li, Hui Wang, Shuo Key Lab of Structures Dynamic Behavior and Control The Ministry of Education Harbin Institute of Technology Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters The Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China School of Civil Engineering Harbin Institute of Technology Heilongjiang Harbin150090 China

ISBN: (数字)9781510653122

ISBN: (纸本)9781510653115

Distributed fiber optic sensing techniques are suitable for pipeline leakage monitoring owing to their long-distance sensing abilities. In this work, a novel pipeline leakage detection and localization method using a distributed fiber optic sensor is proposed. In contrast to conventional methods, the optical fiber is placed in the fluid inside the pipeline without any constraints. When leakage occurs, the local flow field close to the leakage position is disturbed and the fluid pressure caused by the fluid disturbance leads to optical fiber deformation or vibration. With the help of the phase-sensitive optical time domain reflection technique, the fluid disturbance can be detected over a long distance. This work first analyzed the fluid action on the optical fiber. Then, the effects on the fluid field of the local leakage are obtained through finite element simulations. Finally, the proposed method is demonstrated via a series of laboratory experiments. © 2022 SPIE

关键词： Optical fibers

Thermal performance of a novel Trombe wall enhanced by a solar energy focusing approach

学校读者我要写书评

暂无评论

Low-carbon Materials and Green Construction 2024年第1期2卷 379-394页

作者： Xianzhang Dong Huigang Xiao Minglei Ma School of Civil Engineering Harbin Institute of TechnologyHarbin 150090PR China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education (Harbin Institute of Technology)Harbin 150090PR China China Construction Eighth Engineering Bureau Co. LtdShanghaiPR China

The Trombe wall is a passive solar building exterior wall system proposed by Professor Felix Trombe in France,which can collect solar energy to heat buildings without additional energy consumption,making it a focal point of research in building energy ***,its effectiveness is constrained by the low density of solar radiation in winter and the potential for overheating in *** study introduces a novel Trombe wall designed to address these issues through a focused strategy,enabling automatic transition between heating during winter and shading during *** thermal performance parameters of the novel Trombe walls in both winter and summer seasons are examined,and their energy consumption is assessed using experimental research *** indicate that the novel Trombe wall facilitates greater energy savings in both winter and *** compared with traditional Trombe walls,the novel Trombe wall achieves a significant reduction in energy consumption,with up to 55 W/m^(2)in heating load during winter and 47 W/m^(2)in cooling load during *** introduction of this new system holds substantial potential for the realization of zero-energy buildings.

关键词： Trombe wall Thermal performance Focusing approach Overheating

Experimental and Numerical Study on dynamic Responses of a Tlp-Type Modular Floating Structure System

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Li, Yanwei Ren, Nianxin Cai, Wenyu Liu, Yaqiong Ou, Jinping School of Marine Science and Engineering Hainan University Haikou570228 China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan University Haikou570228 China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education China

This paper explores a proposed TLP-type modular floating structure system, incorporating both central TLP modules and peripheral floating artificial reef modules. The outermost floating artificial reef module can function as a floating breakwater, and also serving as a habitat for surrounding marine organisms. Both scale model tests (1:80) and time-domain numerical simulations were performed. The simulations accounted for hydrodynamic interactions among the bodies and the mechanical coupling effects. During the scale model test, a survival strategy has been proposed to prevent collision risks between reef modules and adjacent TLP modules. A preliminary stiffness recommendation was suggested by a trade-off between the pitch of the reef module and the spring force. Numerical and experimental results have been widely compared and discussed. A good agreement has been achieved, although responses are slightly overestimated by numerical simulation due to the neglect of the viscous damping effect. In addition, the responses of the proposed system, connected with and without the outermost floating artificial reef module, have been compared and analyzed. The results suggest that the connection of the reef module can significantly reduce the system's surge response and enhance its survivability under severe sea conditions. © 2024, The Authors. All rights reserved.

关键词： dynamic response

Energy Harvesting of Novel Smart Concrete Based on Nanotechnology: Experimental and Numerical

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Zhang, Mingming Zhu, Lihua Gao, Shan Yuan, Hanquan Liu, Tong School of Civil Engineering Xi’an University of Architecture and Technology Shaanxi Xi’an710055 China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin150090 China

This paper focuses on energy harvesting and smart controls in concrete structures using both experimental and theoretical approaches. The growing demand for sustainable energy solutions has led to innovations in materials like concrete, which offer energy conversion and efficient control possibilities. This study introduces a novel concept for concrete structures using piezoelectric nanoparticles, specifically zinc oxide nanoparticles (ZnO), offering three key benefits: (a) enhanced strength, (b) energy harvesting and storage, and (c) smart control. The experimental phase involves modifying concrete structures with energy harvesting technologies. Dispersion of nanoparticles in water is a key challenge, addressed through magnetic stirring, ultrasonic homogenization, and mechanical stirring. Multiple concrete specimens with nanoparticles were produced, followed by tests including compressive strength assessments, energy harvesting under mechanical loads, and intelligent control of concrete deflection through voltage application. On the theoretical front, modeling and numerical methods predict the behavior of energy harvesting concrete structures. The precise five-parameter theory, accounting for Poisson's effect, is employed for modeling. After deriving governing equations, differential quadrature numerical technique computes deflection and output voltage. Comparisons and validations are made between experimental and simulation results. The experiments reveal that the optimal ZnO nanoparticle content is 0.9%, leading to significant compressive strength improvements of 22.14%, 27.31%, and 34.28% for 7, 14, and 28-day samples, respectively, compared to controls. Beyond this content, compressive strength diminishes. Moreover, 0.9% ZnO-concrete produces an output voltage of 32 volts, well-justified technically and economically. Additionally, +50V voltage induces 9.2mm deformation, while -50V voltage yields 5.8mm, showcasing a substantial 63% deformation alteration potenti

关键词： Energy harvesting

Identification of Chloride Diffusion Coefficient in Concrete Using Physics-Informed Neural Networks

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Wan, Yutong Zheng, Wenzhong Wang, Ying Key Lab of Structures Dynamic Behavior and Control The Ministry of Education Harbin Institute of Technology Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters The Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China

The corrosion of steel caused by chloride is one of the important causes of the deterioration of reinforced concrete structures. In order to describe the transport behavior of chlorides in concrete and to make quantitative durability designs based on it, it is necessary to determine the chloride diffusion coefficient correctly. However, the commonly used analytical method is not suitable for the free chloride diffusion coefficient considering the nonlinear chloride binding capacity of concrete. In this study, by comparing the results of solving forward problems involving chloride transport equations using finite element method (FEM) and solving corresponding inverse problems using physics-informed neural networks (PINNs), it is verified that PINNs can be applied to identify the chloride diffusion coefficient in non-steady-state immersion tests and accelerated chloride migration tests considering no chloride binding, Langmuir binding, or Freundlich binding. The robustness of PINNs is verified by training with 5% noise data as observed data. The results of interpolation and extrapolation using PINNs trained successfully show its excellent generalization performance. © 2023, The Authors. All rights reserved.

关键词： Diffusion