As Deputy Chief Engineer of Program Operations and Asset Management of , Justine Tietjen (nee Lorentzson) is responsible for the overall strategic planning and management of the Capital Program—as well as other special programs—and management of E&C’s implementation of the Authority-wide Asset Management program. Ms Tietjen leads a 15-person professional engineering organization including the Program Oversight Unit, Estimating and Scheduling Unit and the E&C asset management unit.

Ms Tietjen has been with since 2003 and has previous experience in the private sector in engineering consulting implementing major public works projects in the New York area. In addition, Ms Tietjen also has extensive experience with Ohio Department of Transportation in the field of highway engineering.

As Chairperson of ICSBOA, Ms Tietjen has authored several technical papers on the subject of cable supported bridge suspension elements and is the primary author of a chapter for the book Inspection, Evaluation and Maintenance of Suspension Bridges Case Studies published in 2015.

A licensed professional engineer in both New York and Ohio, Justine Tietjen holds a Bachelors of Science degree in Civil Engineering from Akron University, a Bachelors of Arts degree in Music from Marietta College, Ohio, and a Master of Science degree in Biological Sciences from State University of New York at Stony Brook.

David Bishop is a Chartered Civil and Structural Engineer with over 18 years of experience in the design, assessment, and management of major bridge infrastructure across the UK. Holding a Master of Engineering in Civil Engineering from Heriot-Watt University, he is a Chartered Engineer and a member of both the Institution of Civil Engineers and the Institution of Structural Engineers.

Throughout his career, David has built a strong reputation for delivering complex bridge engineering projects, combining deep technical expertise with proven leadership and project management capability. He has held key roles including Bridge Designer, Project Manager, Project Director, and Major Bridge Manager, contributing to the successful delivery and maintenance of some of the UK’s most significant structures, including the Forth Road Bridge, the M48 Severn Bridge, the Humber Bridge, and the Queensferry Crossing.

David currently oversees the operation, inspection, maintenance, and strategic management of all trunk road bridges within the South East Scotland network. This includes responsibility for iconic assets such as the Forth Road Bridge and the Queensferry Crossing. In this role, he leads multidisciplinary teams of around 90 staff, delivering programmes of structural assessment, capital upgrades, and emergency works. He ensures safety, reliability, and value for clients, successfully managing an annual programme of works valued at £40 million.

He has extensive experience in structural assessment and advanced analysis of suspension and cable‑stayed bridges, including nonlinear and finite element modelling. In addition to his project work, David has contributed to industry knowledge through published papers on bridge maintenance, design, and assessment, earning recognition for excellence in bridge engineering research.

Xianghui Chen is currently the director of the Technical Expert Committee of Jiangsu Communications Holding Co., Ltd in China, after serving as the deputy general manager of the company for many years. He is responsible for the management, operation, and maintenance of large-span cable-supported bridges such as Jiangyin Yangtze River Bridge, Runyang Yangtze River Bridge, Sutong Yangtze River Bridge, Taizhou Yangtze River Bridge in Jiangsu Province. Through his innovative contributions in technological progress and administration, the structural durability and safety of cable bridges were improved, which won several provincial and ministerial technological progress awards.

Xianghui Chen is the member of the Expert Committee of the China Highway and Transportation Society, the executive committee member of the Jiangsu Provincial Comprehensive Transportation Society, and the deputy director and secretary-general of the Expert Advisory Committee. He is a professional researcher-level senior engineer, and received a special government allowance from the State Council due to his achievements in engineering and technology.

Xianghui Chen organized the 7th ICSBOC (Zhenjiang) and the 10th ICSBOC (Nantong) both in Jiangsu Province in 2010 and 2018 respectively. As the executive chairman of both conferences, he contributed to the technological exchanges on management and maintenance of cable-supported bridges.

Xianghui Chen holds a bachelor’s degree in civil engineering from Southeast University and an MBA from Nanjing University and the Maastricht School of Management in the Netherlands.

Kiyohiro Imai is the Senior Director of the Corporate Planning Department of Honshu-Shikoku Bridge Expressway Company Limited (HSBE). He has been involved in the construction and maintenance of the Honshu-Shikoku Bridge as a bridge engineer for more than 30 years. He was involved in the design and construction of the Akashi Kaikyo Bridge and the Kurushima-Kaikyo Bridges, and the maintenance of the Ohnaruto Bridge.

In 2003, Kiyohiro Imai and Prof. Dan M. Frangopol received the Moisseiff Award from the American Society of Civil Engineers (ASCE) for their contributions to research on the reliability evaluation of suspension bridges. He has been involved for more than 10 years in the activities of the Permanent International Association Road Congress (PIARC), which continues to promote global discussion and knowledge about roads and road transport. Since 2016, he has been the Chair of PIARC Technical Committee on Road Bridges. In 2020, he was awarded the 2020 IABMAS SENIOR PRIZE for his work on the construction and maintenance of the Honshu-Shikoku Bridges, his research on bridges in the USA, and his work on the PIARC Technical Committee.

In 2022, Kiyohiro Imai was approved to represent HSBE on a board member of the International Cable-Stayed Bridge Operators Association (ICSBOA).

Kiyohiro Imai received his B.S. and M.S. degrees in civil engineering from Kyoto University and his Ph.D. degree in civil engineering from the University of Colorado at Boulder, USA.

Kim Agersoe Nielsen is the Head of Department, Structures and Landworks, Sund & Bælt Holding A/S. As an experienced Head Of Department, Kim has a demonstrated history of working in the transportation/trucking/railroad industry. He is skilled in bridges, infrastructure, power plants, renewable energy, engineering and project engineering. Kim has a strong professional education with a Master of Science (M.Sc.) focused in Mechanical Engineering from Danmarks Tekniske Universitet / DTU.

In his role as Deputy Commissioner and Chief Bridge Officer, Mr. Schwartz oversees all aspects of design, construction, rehabilitation and reconstruction, maintenance, operation and administration of the 806 bridges, 4 vehicular tunnels and 650 retaining walls under the jurisdiction of the New York City Department of Transportation.

He is responsible for formulating policy and providing executive and administrative direction for the Division of Bridges with a team of nearly 650 engineers, technicians, tradespeople, planners and administrators. He has served the Bridges Division for over 20 years having joined City DOT in the fall of 2002.

He holds a Bachelor of Science Degree in Operations Research and Industrial Engineering from Cornell University, College of Engineering and is a licensed Professional Engineer in the State of New York.

Currently there are over 40 bridge and tunnel projects in various stages of design and well over $2 billion worth of construction projects in progress.