Xilin Lü

Professor

Tongji University, China

Profile: Xilin Lü is a professor, a doctoral advisor at the Department of Underground Construction and Engineering of Tongji University, the director of the Institute of Foundation Engineering as well as a national high-level young talent. Professor Lü is mainly engaged in soft soil underground engineering, digital intelligent construction, progressive failure of geotechnical bodies, and high-performance numerical algorithms. He has presided over five national key projects, including National Key Research and Development Programs for International Cooperation and the National Natural Science Foundation of China, and has undertaken more than 20 other national and provincial projects. He has been recognized with plentiful awards, such as over 10 first and second prizes for scientific and technological progress from provincial and ministerial levels and national industry associations and the Huang Wenxi-Chen Zongji Youth Award in Geotechnics. Boasting over 100 publications to his credit, Professor Lü has authored two books, obtained 30 international and domestic patents, and contributed to the editing of four national, local, and industry standards and specifications. He is a member of the Computational Geotechnical Committee of the American Society of Civil Engineers (ASCE), a communication committee member of the International Society of Geotechnical Engineering (ISSMGE) - TC214 and TC222, an executive director of the Geotechnical Foundations and Structural Engineering Branch of the Chinese Society of Rock Mechanics and Engineering, and a director of the Engineering Diagnosis, Treatment, and Operation & Maintenance Branch of the Architectural Society of China. Additionally, Professor Lü also serves as an associate editor of Geoenvironmental Disasters, an editorial board member of the Journal of Applied Basic and Engineering Sciences and Foundation Treatment as well as a youth editorial board member of journals such as the China Journal of Highway and Transport.

Title: Experimental Study and Numerical Simulation of the Instability of Shield Tunnel Face in Sand Under Complex Conditions

Abstract:The shield tunneling method is widely adopted in soft soil areas. Maintaining the stability of shield tunnel faces is crucial during the tunneling process because the instability of excavation surfaces may lead to excessive soil deformation or even collapse, thereby affecting nearby facilities. Therefore, this report focuses on the stability of shield tunnel faces under complex conditions, including initial anisotropy, groundwater seepage, and soil degradation in the sandy strata. Through model tests and numerical simulations, we systematically analyzed the destabilization damage modes of shield tunnel faces and the changes in ultimate support pressure caused by these factors. The research results provide theoretical support for the design and construction safety control of related projects.

Le Wang

Associate Researcher / Senior Engineer

Tianjin University, China

Profile: Le Wang earned his Ph.D. from Tianjin University, where he currently serves as an Associate Researcher and a Senior Engineer at the School of Civil Engineering. Dr. Wang’s research is dedicated to the interaction between marine foundations and soil, with a particular emphasis on the force mechanisms of helical anchor foundations during non-steady rotational installation, the load-bearing performance of these anchors under inclined cyclic loads, and the behavior of large-diameter single piles and group piles in stratified soils.

Title: Study on the Force Mechanism of Non-steady Rotational Installation Process of Large-scale Helical Anchor Foundations for Floating Wind Turbines

Abstract:The non-steady rotational installation method offers an innovative technique aimed at substantially reducing the torque and pressure during the installation of helical anchors. Revealing the force mechanisms involved in this process is a critical scientific issue for the effective deployment of helical anchors in floating wind turbine projects.

This presentation discusses the team’s recent work, including physical model experiments and numerical simulations related to this technique, highlighting future research directions. The outcomes of this research provide essential theoretical support and practical strategies for the optimized design of large-scale helical anchor foundations in floating wind turbine applications.

Chao Liang

Senior Engineer

Tianjin University, China

Profile:Dr. Liang Chao is a postdoctoral researcher and Assistant Researcher/Senior Engineer at the School of Civil Engineering, Tianjin University. His primary research interests include the load-bearing characteristics of marine engineering pile foundations and the interaction between marine geotechnics and structures. As the first or corresponding author, he has published 13 papers in SCI/EI-indexed journals and holds 10 authorized patents. He has led three national and provincial projects, including sub-projects of the National Key Research and Development Program of China and the Tianjin Natural Science Foundation, as well as four engineering projects. Additionally, he has contributed to the drafting of two industry standards and has been awarded two provincial science and technology progress awards for his research achievements.

Title:Research on Bearing Capacity and Structural Integrity of Composite Piles with Variable-Diameter Shafts
Abstract:China’s marginal oil fields, characterized by their “marginal, small, and fragmented” nature, have substantial total reserves but remain underdeveloped due to cost constraints. When wellbores serve as support structures for platforms, the interaction mechanisms between the pile and soil and the load transfer mechanisms under additional axial loads and coupled thermal loads within the wellbore are not well understood. This lack of clarity hinders the effective evaluation of the load-bearing performance of wellbores, limiting their application in the construction of marginal oil field platforms. This study focuses on composite piles with ultra-long variable-diameter shafts, which are composed of conductor pipes, surface casings, and cement grout. We investigated the load transfer mechanisms within the pile shaft under additional loading, uncovering the stress and bearing capacity evolution patterns of the pile shaft. We developed a method for calculating the bearing capacity of composite piles considering the variable cross-section effect and established a non-linear pile-soil interaction curve. Additionally, we explored the impact of coupled axial and thermal loads on the bearing capacity of composite piles. Finally, through static load testing in the field, we validated the applicability of the bearing capacity calculation method for wellbore composite piles.

Zhichao Dong

Senior Engineer

CCCC First Harbor Engineering Co. Ltd., 

Tianjin Port Engineering Institute Co., Ltd. of CCCC First Harbor Engineering Co., Ltd., China

Profile: Zhichao Dong obtained his Ph.D. in Civil Engineering from Tongji University and is a distinguished young talent in the CCCC Corporation. He currently works at the Technical Center of CCCC First Harbor Engineering Co., Ltd. Dr. Dong has been deeply involved in several major projects, including the Dalian Bay Undersea Tunnel, the Guangming Road Extension, the Shenzhen–Zhongshan Bridge, and the water intake for the Hongyanhe Nuclear Power Plant. His innovations include a predictive method for underwater rock dumping drift considering wind, wave, and current effects, the development of a localized marine dynamic forecasting and hindcasting system, a wave observation device using RTK-GNSS for small amplitude waves, and a novel sludge dewatering technology combining nanotechnology with traditional soft ground treatment processes. Dr. Dong has led or participated in six youth innovation projects at CCCC and contributed to nine research projects funded by the National Natural Science Foundation of China, provincial and ministerial technology projects, and key CCCC R&D initiatives. He has published 22 academic papers, holds four invention patents, and has been awarded the second prize for scientific and technological progress by the China Highway Construction Association.

Title:Key Design and Construction Technologies for Curved Flexible Pipe-Jointed Undersea Tunnels under Complex Conditions

Abstract:This research addresses the challenges posed by the construction of flexible pipe-jointed tunnels with small curvature radii undersea, specifically dealing with uneven geological conditions and complex external environments. The study focuses its attention on critical technologies, including segment structure, foundation design, bedding leveling for curved sections, and immersed pipe installation. Using theoretical research, numerical simulations, and field tests, it investigates the key design and construction technologies for curved flexible pipe-jointed undersea tunnels under these complex conditions. Innovative contributions include the introduction of a shear resistance structure for segment joints, enhancing the structural design of flexible pipe joints, improving the adaptability of immersed tunnels to varying ground conditions, and boosting its structure. The study reveals the deformation mechanisms of the gravel bed layer under vertical loads and examines how uneven geological conditions affect structural forces and the load-bearing capacity of segment joints, providing theoretical support for the foundation design of immersed tunnels. The research proposes a method for laying gravel beds for immersed tunnels with small curvature radius, addressing the issues of gap and height differences at segment edges due to the curved pipe sections. It also uncovers the movement patterns during the pulling and positioning process of curved immersed pipes and derives a formula to calculate the maximum deflection during this process. The study further proposes pre-control techniques for the installation of immersed tunnels with small curvature radius on pre-laid beds, achieving precise alignment of curved segments. The findings from this research provide robust support for the implementation and cost control of the Dalian Bay Undersea Tunnel project. They offer valuable references for the construction of immersed tunnels both domestically and internationally and significantly contribute to enhancing the immersed tunnel industry. 

Xu Liu

Engineer

CCCC First Harbor Engineering Co. Ltd.

Profile:Dr. Liu Xu holds a Ph.D. in Geotechnical Engineering from Tianjin University and currently works at the Technical Center of CCCC First Harbor Engineering Co., Ltd. His work focuses on geotechnical theoretical analysis and technological development in marine engineering. Dr. Liu has led or participated in over ten research projects at various levels, including national and provincial projects. His research primarily addresses foundation treatment techniques for immersed tunnels and artificial islands.

Title: Comprehensive Key Technologies and Applications in the Construction of the Shenzhen-Zhongshan Bridge Island-Tunnel Project

Abstract:This presentation provides an overview of the Shenzhen–Zhongshan Bridge Island-Tunnel project, detailing its scope, engineering challenges, technological achievements, and innovations. The Shenzhen–Zhongshan Bridge, following the Hong Kong-Zhuhai-Macao Bridge, is another monumental project situated in the core of the Guangdong-Hong Kong-Macao Greater Bay Area. It is a world-class mega-project combining offshore bridges, artificial islands, immersed tunnels, and underwater interchanges. The project boasts vast scale, stringent construction standards, complex conditions, and significant design and construction difficulties. Additionally, it poses high safety risks, strict environmental requirements, innovative structural forms, and substantial technological challenges. In adherence to the principle of balancing tradition with innovation, the project focuses on solving on-site issues under the guidance of industrialization, digitalization, and smart technologies. Under the leadership of CCCC First Harbor Engineering Co., Ltd, a collaborative effort has led to the development of nine key technologies to tackle these challenges, such as the rapid construction of large-diameter steel cylinder islands in complex geological conditions. These technological advancements have proven highly effective in their application.