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SSRN 2022年

作者： Bai, Shuai Guan, Xinchun Li, Guoyu Key Lab of Structures Dynamic Behavior and Control The Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters The Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China Harbin Institute of Technology Harbin150090 China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou730000 China

This study investigated the influence of nano-silica dosages and hydration temperatures on the early-age hydration heat of cement using isothermal calorimetry, and a hydration kinetics model was used to analyze the nucleation and growth rates of hydrates. The calorimetry results show that the addition of nano-silica and the increase of hydration temperature can accelerate the process of hydration reaction. As the dosage of nano-silica increases, the induction period decreases, the acceleration period and exothermic rate peak value increase. The fast pozzolanic effect of nano-silica is responsible for accelerating the hydration reaction. However, the excessive addition (5%) of nano-silica may form many agglomerations, thereby inhibiting the modification effect of nano-silica on the cement hydration. The simulating results of kinetic parameters show that, at three hydration temperatures, the nucleation rate of hydrates increase with the increasing of nano-silica dosages, which indirectly confirms the nucleation effect of nano-silica in the early-age hydration. At 20 °C and 30 °C, the growth rate of hydrates also increases with the increasing of nano-silica dosages. At 40 °C, the growth rate of hydrates is decreased gradually, possibly due to the lack of sufficient Ca2+ and H2SiO42-. In addition, the nucleation rate is more sensitive and the growth rate is less sensitive to the hydration temperature. © 2022, The Authors. All rights reserved.

关键词： Hydration

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Damage Detection of Transmission Tower Based on Stochastic Subspace and Statistic Model 3

Damage Detection of Transmission Tower Based on Stochastic S...

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3rd International Conference on Environmental Prevention and Pollution control Technologies, EPPCT 2021

作者： Xingjie, Wang Tingting, Yang Meigen, Cao Chong, Zheng Wensong, Zhou Yutong, Pang Wenzhou Power Supply Company of State Grid Zhejiang Province Wenzhou330300 China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Heilongjiang Province Harbin150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters Ministry of Industry and Information Technology Harbin Institute of Technology Heilongjiang Province Harbin150090 China School of Civil Engineering North China University of Technology Beijing100144 China

During the long service period of the transmission tower, the severe environment, material aging and fatigue effects result in the damage accumulation and resistance fading of the transmission tower, which even lead to the structural failure. In this paper, a stochastic subspace-based damage detection algorithm combined with statistical model is proposed for the damage identification of transmission tower structures through processing and analysing its vibration signals. Based on the structural modal parameters identified from the structural vibration response, the nominal modal parameters are defined. Considering that the Hankel matrixes constructed by the system observability matrix and the system output covariance matrix have the same kernel space, the damage index sensitive to the modal parameters is constructed. In the manuscript, firstly, the damage index establishment method and process of the algorithm are presented;and then the vibration data of transmission tower structure simulation under different damage conditions are obtained through numerical simulations;finally, above data are analysed to obtain the damage identification results of transmission tower. The results show that the method proposed in this work can effectively identify the local damage of transmission tower structure. © Published under licence by IOP Publishing Ltd.

关键词： Stochastic systems

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Efficient structural seismic performance evaluation method using improved endurance time analysis

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 795-809页

作者： Li Shuang Liu Kun Liu Xiangyang Zhai Changhai Xie Fengwei Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin 150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin 150090 China

Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dynamic analysis (IDA) method or pushover method. The recently developed endurance time (ET) method is another method that uses dynamic pushover excitations, i.e., endurance time acceleration function, to obtain results similar to those obtained by IDA or pushover methods with low computational cost and acceptable accuracy. This study proposes an improvement on the ET method by considering more restrictions for both the elastic and inelastic response spectra in the generation procedure, and by specifying a target duration. Four reinforced concrete frame structures with 4, 8, 12, and 16 stories are adopted to verify the accuracy of the improved method. Comparison of the results obtained by the proposed method, the ET method and the IDA method shows that the improved method has a higher accuracy than the ET method. For evaluation of structural responses under specifi c ground motion intensity, which is typically required in seismic design codes, the results obtained by the proposed method are compared with fi ve commonly used ground motion selection methods, and shows the proposed method provides acceptable accuracy for engineering applications.

关键词： seismic performance evaluation endurance time method inelastic response spectra target duration

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Development of dimensionless P-I diagram for curved SCS sandwich shell subjected to uniformly distributed blast pressure

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1432-1445页

作者： Yonghui WANG Ximei ZHAI Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China

The curved steel-concrete-steel(SCS)sandwich shell was recently proposed to resist blast loading and it showed better blast resistant performance as compared to flat SCS sandwich shell via developing compressive force along the *** this paper,a dimensionless Pressure-Impulse(P-I)diagram was constructed as a convenient tool to predict the damage level of curved SCS sandwich shell subjected to uniformly distributed blast *** curved SCS sandwich shell was equivalent to a single-degree-oMreedom(SDOF)system and the equation of motion was established by employing the Lagrange's *** construct the dimensionless P-I diagram,the energy balance method was utilized to yield the pressure and impulse asymptotes and the responses in the dynamic response regime were obtained via employing the SDOF ***,the finite element method was employed to validate the developed dimensionless P-I ***,the procedures of using the constructed dimensionless P-I diagram to quickly conduct the blast resistant design of curved SCS sandwich shell were presented.

关键词： blast loading curved steel-concrete-steel sandwich shell Pressure-Impulse diagram single-degree-of-freedom method finite element analysis

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Aerodynamic design and analysis for offshore wind turbine blade model

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Energy 2025年 330卷

作者： Ziyang Zhang Wen-Li Chen Jiabin Liu Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin 150090 China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin 150090 China

Model experiments are essential for designing and analysing offshore wind turbines. During the scaling process of the model, the rotor thrust significantly decreases due to the Reynolds number effect. As wind turbines increase in size, blade length also gradually increases. The scaling ratio of the model decreases due to lab.ratory size constraints, affecting the structural loading characteristics. Therefore, this study performs an aerodynamic design for model blades, considering the Reynolds number effects and geometric dimensions. The optimised blade satisfies the scaled model's thrust requirements when its length is shorter than the scaled prototype blade. We employed the low Reynolds number airfoil SG 6043 to optimise the model blade. The geometric parameters of the optimised blades were calculated using the blade element momentum theory and pattern search method. Wind tunnel experiments were conducted on the optimised blade to analyse the variation characteristics of rotor thrust. The research results show that the numerical calculation results of rotor thrust generally align with the experimental results. The rotor thrust of the optimised blades was significantly enhanced, meeting the scaled model's thrust requirements. The error between the optimised blade's rotor thrust and the scaled target value is less than 2 %.

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Experimental and numerical studies on axial residual capacity of HSCHS tube after lateral impact

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Thin-Walled structures 2025年 215卷

作者： Yang, Kaiyun Zhai, Ximei Gao, Huaxiao 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

In this paper, experimental works of 19 impacted high-strength steel circular hollow section (HSCHS) specimens and one non-impacted specimen were carried out, to obtain their axial residual compressive performance subjected to compressive loading The experiments were performed using an electro-hydraulic servo press, and the results were analyzed in terms of failure mode, load–displacement relationship, strain, and deformation. The effect of impact energy, diameter-to-thickness ratio, axial compression ratio and hammer head type on the axial residual capacity of HSCHS tubes was investigated. The failure modes observed from the tests presented a combination of overall instability and local buckling. The finite element (FE) model of HSCHS tube subjected first to lateral impact and then to axial compression loading was established using nonlinear FE analysis platform ANSYS/LS-DYNA. After verifying the accuracy of the FE model by comparison with the test results, a parameter analysis was conducted to reveal the influence of impact energy, diameter-to-thickness ratio, axial compression ratio, impact location and slenderness ration on axial residual capacity. Finally, based on the FE analysis, two simplified calculation equations were proposed to predict the axial residual capacity of HSCHS tube, providing reasonably good correlation with the experimental results. © 2025

关键词： Buckling modes

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Experimental Study of High-Temperature Resistance of Alkali-Activated Slag Crushed Aggregate Mortar

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SSRN 2022年

作者： Huang, Wenxuan Wang, Ying Zhang, Yaming Zheng, Wenzhong School of Civil Engineering Harbin Institute of Technology Haihe Road #202 Nangang District Harbin150090 China Key Lab of Structures Dynamic Behavior and Control Ministry of Education Key Lab Smart Prevention and Mitigation of Civil Engineering Disasters Ministry of Industry and Information Technology School of Civil Engineering Harbin Institute of Technology Haihe Road #202 Nangang District Harbin150090 China

In this research, a special type of mortar with alkali-activated slag as cementitious material was examined, which had the characteristics of high strength, high temperature resistance and environmental protection. Its aggregates consisted of crushed and sieved particles of alkali-activated slag paste. The compressive strengths of 126 cubic and 126 prismatic specimens during and after high-temperature treatment were investigated. The test results showed that both the compressive and flexural strengths of the mortar during and after high-temperature treatment decreased with increasing temperature. Moreover, the compressive strength of the mortar after high-temperature treatment was higher than that during the treatment in which strength grade and temperature were constant. The high-temperature strength loss of the mortar was also found to be lower than that of concrete. The formulated equations for calculating the compressive and flexural strengths during and after high-temperature treatment provided a basis for evaluating the fire resistance of this new type of masonry material. The microstructure and composition of the mortar were analyzed using scanning electron microscopy with energy-dispersive spectrometry and X-ray diffraction. At 600 ℃, the mortar gradually produced new melilite products. © 2022, The Authors. All rights reserved.

关键词： Compressive strength

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Preparation and Properties of a Cement-Based Permeable Crystalline Repair Material

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SSRN 2021年

作者： Lu, Rongwei Guan, Xinchun Zhang, Chenchen Kou, Yufeng Li, Jinglu Li, Yazhao Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters Ministry of Industry and Information Technology Harbin Institute of Technology Harbin150090 China Harbin Institute of Technology Harbin150090 China

According to the performance requirements of concrete repair materials, a new cement-based permeable crystalline repair material（CCRM） was prepared, and its repair performance and repair mechanism were studied by means of macro mechanical property test, micro ESEM and XRD. The experimental results show that the prepared repair material not only has good flow performance and strength, but also enhances the strength of the repair interface, so that the repair interface is no longer the weak point of the repaired specimen. Through the observation of the microstructure of the repaired specimen, it is found that CCRM can penetrate into the interface of the repaired specimen to form a cross transition zone, and then form a better integration with the repaired specimen, with very good compatibility. Through the test of CCRM repair products by XRD and TG, it is found that there is an active component in CCRM, which can consume calcium hydroxide to form a complex, promote the transformation of calcium carbonate and C-S-H, and then enhance the repair effect. © 2021, The Authors. All rights reserved.

关键词： Repair

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Buckling behaviour of S700 high strength cold-formed steel built-up I-section columns

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Journal of Constructional Steel Research 2025年 233卷

作者： Zhuo Wang Chicheng Ma Hua Yang Andi Su Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of Technology Harbin 150090 China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of Technology Harbin 150090 China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Nanning Guangxi 530004 China

High strength cold-formed steel (CFS) built-up sections have been widely used in the construction sector, mainly due to high load-bearing capacities and flexible cross-section shapes. To further broaden the knowledge and develop efficient design provisions for high strength CFS built-up sections, experiments and numerical simulations were conducted to investigate the local–flexural interactive buckling behaviour and resistances of S700 high strength CFS built-up I-section columns. In the physical experiments, two identical unlipped channel sections were adopted to assemble each built-up I-section in a back-touching configuration with self-tapping screws. Material testing and measurements of initial geometric imperfections were first conducted; nine column specimens of two cross-sections – 90 × 70 × 2.9 and 160 × 100 × 2.9 were employed and then tested under pin-ended boundary conditions. In the numerical simulations, finite element (FE) models were developed and observed to precisely capture experimental observations. A parametric study was then conducted to derive additional numerical data across a wider range of geometric parameters and member slenderness. After that, the effective width method (EWM) in the European code and American specification, and the direct strength method (DSM) in the American specification were assessed, according to the experimental and numerical results, for their applicability to S700 high strength CFS built-up I-section columns failing by minor-axis local–flexural interactive buckling. The assessment results showed that the EWM yielded scattered and conservative results, while the DSM resulted in relatively accurate but still overall conservative resistance predictions. Therefore, a revised AISI design approach was proposed to improve design consistency and accuracy, with its reliability also verified.

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Experimental Study and Finite Element Analysis on Impact Resistance of Offshore Wind Turbine Steel Truss Foundation

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SSRN 2023年

作者： Shi, Chenglong Zhang, Jigang Liu, Feifei Chen, Wenli Zhao, Guoliang Gu, Chi Song, Hanyu School of Civil Engineering Qingdao University of Technology Qingdao266520 China Co-operative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic Zone Qingdao266033 China Key Lab of Structures Dynamic Behavior and Control the Ministry of Education Harbin Institute of Technology Harbin150090 China Qingdao First Municipal Engineering Co. Ltd. Qingdao266000 China China Shanghai Architectural Design &Research Institute Co. Ltd. Shanghai200062 China

In recent years, the global offshore wind turbines(OWTs) have been developing rapidly towards the deep sea. Offshore wind turbines are at risk of ship collisions during their installation and operation. In this paper, the pendulum impact test and finite element simulation analysis are carried out to study the impact load resistance of steel truss foundation of offshore wind turbine in Bohai Sea. The impact resistance of steel truss foundation was analyzed from the parameters of failure modes, impact response and energy dissipation capacity through multiple pendulum impact tests. The results show that after two impacts the stiffness of the impact leg is significantly reduced and even fracture at its foot. The branch tube near the point of impact are squeezed and bent, and the deformation and acceleration peak of the impact position are the largest. The denting of the impact leg is the main energy dissipation mechanism. An energy dissipation coefficient is proposed which can help to predict such a structure’s impact resistance. These data provide an experimental basis for improving the impact resistance of full-scale offshore wind turbine structures. © 2023, The Authors. All rights reserved.

关键词： Energy dissipation

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