Zhenzhong Hu

    He received both his BE and PhD degree in the Department of Civil Engineering at Tsinghua University, China. He was a visiting researcher in Carnegie Mellon University.
    He is now the associate professor in Shenzhen International Graduate School, Tsinghua University, and also the secretary general of the BIM Specialty Committee of the China Graphics Society.
    His research interests include information technologies in civil and marine engineering, building information modeling (BIM) and digital disaster prevention and mitigation.
  • 2024-05-06

    2024-05-06

    The paper titled "Fine-tuning vision foundation model for crack segmentation in civil infrastructures" has been published in the journal Construction and Building Materials.

    Large-scale foundation models have become the mainstream deep learning method, while in civil engineering, the scale of AI models is strictly limited. In this work, a vision foundation model is introduced for crack segmentation. Two parameter-efficient fine-tuning methods, adapter and low-rank adaptation, are adopted to finetune the foundation model in semantic segmentation: the Segment Anything Model (SAM). The fine-tuned CrackSAM shows excellent performance on different scenes and materials. To test the zero-shot performance of the proposed method, two unique datasets related to road and exterior wall cracks are collected, annotated and open-sourced, for a total of 810 images. Comparative experiments are conducted with twelve mature semantic segmentation models. On datasets with artificial noise and previously unseen datasets, the performance of CrackSAM far exceeds that of all state-of-the-art models. CrackSAM exhibits remarkable superiority, particularly under challenging conditions such as dim lighting, shadows, road markings, construction joints, and other interference factors. These cross-scenario results demonstrate the outstanding zero-shot capability of foundation models and provide new ideas for developing vision models in civil engineering.

    Note: The first author of this paper is Ge Kang, a master's student in 2022, and Assistant Professor Guo Yutao is the corresponding author. The research findings were supported by  the National Natural Science Foundation of China and tthe Cross-disciplinary Research and Innovation Fund Research Plan of Tsinghua Shenzhen International Graduate School.

  • 2024-03-24

    2024-03-24

    Recently, Huaxia Construction Science and Technology Award Committee released the "2023 China Award for Science and Technology in Construction" award project list, by my participation in the completion of the "Key technologies and applications of digital construction for urban metro driven by digital twins" project, won the 2023 "China Award for Science and Technology in Construction" second prize.

    China Award for Science and Technology in Construction is one of the most influential science and technology awards in the field of housing and urban and rural construction in China, aiming to recognize organizations and citizens who have made significant contributions to the construction industry, promote the application of scientific and technological achievements and productivity transformation, and improve the overall technical strength of the housing and urban and rural construction industry. Our team won this award, which fully reflects our technical strength and innovative value in the field of digital twin technology and urban subway construction. In the future, we will continue to improve our technologies and methods, promote the process of digital transformation and upgrading, and contribute to the development of urban transport infrastructure.

    Note: The project was led by myself, Wang Wei, Lin Jiarui, Zou Dong, Zhang Jianping, Guo Yutao, Wang Hongdong, Cui Libo, Xue Zhigang, Chen Xiangxiang, Wu Zhen and Zhang Bangchao were the main practitioners. The main completion units include Guangzhou Metro Group Co., LTD., Tsinghua SIGS, Tsinghua University, Guangzhou Metro Construction Management Co., LTD., China Railway Construction South China Construction Co., LTD., Guangzhou Rail Transit Construction Supervision Co., LTD., Beijing Cloud Construction Technology Co., LTD. 

  • 2024-02-27

    2024-02-27

    Inertia load reduction for loadoff during floating offshore wind turbine installation: Release decision and ballast control has been published in the journal Sustainable Horizons.

    High offshore installation costs are a significant factor limiting the competitiveness of offshore wind energy. One efficient installation approach for floating offshore wind turbines is to preassemble the tower, nacelle, and rotor onshore and perform a single lifting operation to mate the superstructure with the floating foundation at the installation site. It is heavy lifting, due to the weighty payload. At the end of the mating process, a loadoff operation is conducted to transfer the preassembly to the floating foundation. It results in a sudden change in total force acting on the vessel and causes substantial acceleration and potential damage to the mechanism in the onboard nacelles. The magnitude of acceleration of the onboard nacelles can vary greatly at different release instants. In this research, a simplified two-degrees-of-freedom (DOF) (heave and pitch) model is also proposed to account for the heavy lifting process and variable ballast tanks. The sudden payload transfer is approximated using a hyperbolic tangent function to guarantee continuity and differentiability. The loadoff operation consists of the decision-making and vessel-stabilizing phases. Based on the nonlinear model predictive control method, a payload-transfer time selector and anti-pitch ballast controller have been developed to achieve optimal release time decisions and stabilize the vessel after payload release, respectively. Six-DOF simulation results show that the proposed algorithms are capable to a satisfying level of robustness of deciding the optimal payload release time instant, as well as limiting the peak and mean acceleration magnitudes of the onboard nacelles after payload release. The decision-making and control strategies may promote the sustainable energy transformation by extending the operation window and reduce the installation costs.

    Note: The first author of this paper is Ma Can, a master's student in 2021, and Assistant Professor Ren Zhengru is the corresponding author. The research results were supported by Shen-zhen Science and Technology Program, Shen-zhen Science & Technology Commission, and Shenzhen Science and  the Guangdong Basic and Applied Basic Research Foundation.

  • 2024-02-19

    2024-02-19

    The Probability of Ship Collision during the Fully Submerged Towing Process of Floating Offshore Wind Turbines have been published in the journal Sustainability.

    In the context of the rapid development of the green energy industry, the Floating Offshore Wind Turbines (FOWTs)  project is the focus of the current green sustainable development of energy. However, most studies have focused on the design and manufacture of the Wind Turbines before installation and the movement and response after installation, and have studied less the collision risk that is most likely to occur during the towing of the FOWTs to the site. Based on the analytical model construction method, this study takes the Wanning Floating Offshore Wind Farm (FOWF)  as the research object, expands on the widely recognized Pedersen collision probability assessment model, and creatively develops the probability assessment calculation model of collision with other ships during the towed transport of FOWTs in non-channel areas. The results show that the probability of ship collision in towed transport is mainly affected by regional ship density, distribution and sailing speed. This study makes up the gap in the field of risk assessment during installation of deep-water FOWTs.

    Note: The first author of this paper is Li Yihong, a postdoc, and I am the corresponding author. The authors also include Liu Longxiang, a master's student, and Associate Professor Li Sunwei. The research results were supported by Guangdong Basic and Applied Basic Research Foundation and Shenzhen Science and Technology Commission.

  • 2024-01-30

    2024-01-30

    "A mechanical analysis method and system for fan installation based on digital twin" has obtained the invention patent certificate (patent number: ZL202311306512.6).

    The invention discloses a mechanical analysis method and system for fan installation based on digital twin, which comprises the following steps: obtaining the basic information of the rod structure; According to the basic information of the bar structure, a bar element set and a load set are generated; According to the bar element set and the load set, the global stiffness matrix and the external load vector in the compressed sparse row matrix format are integrated. According to the global stiffness matrix and the external load vector, the global displacement vector is obtained by the conjugate gradient method. According to the global displacement vector, a set of deformed member elements is obtained. According to the set of deformed bar elements, the stress distribution results of the bar structure are obtained. The invention accelerates the storage and solving efficiency of the matrix without loss of effective information, so that the calculation accuracy can be taken into account while the calculation efficiency can be effectively improved, and the rapid modeling and calculation of complex and large structures can be realized.

    Note: The inventors of this patent also include doctoral student Min Yantao, Academician Zhang Jianmin, doctoral student Liu Yi, master student Ning Houchun, Associate Professor Li Sunwei and Associate Professor Li Binbin.