In recent years, the convergence of computational methods and artificial intelligence (AI) has revolutionized various domains across science, engineering, and industry. This special issue aims to explore the exciting advancements, potential, and challenges in the field of computational methods enhanced by artificial intelligence. By harnessing the power of intelligent algorithms, researchers have unlocked new frontiers in problem-solving and decision-making, enabling innovative solutions for complex and large-scale problems. Computational methods have long been used to model and analyze real-world phenomena, ranging from physical processes to social dynamics. However, the advent of AI techniques, such as machine learning, deep learning, and natural language processing, has introduced a new paradigm, empowering computational methods with enhanced problem-solving capabilities. These intelligent algorithms can process vast amounts of data, extract meaningful patterns, and make accurate predictions, thus augmenting the traditional computational methods with unprecedented efficiency and accuracy.

Rapid urbanization results in the great development of underground facilities. This is underlined by the rapidly increasing number of metro lines, utility tunnels, water conveyance tunnels, underground stations, underground cities, underground garages, and underground storages for water, grains, data devices, etc. High utilization of urban underground space (UUS) requires Intensive Construction Technology (ICT). The latter refers to the reduction of precious resources, e.g. land, time, and cost, used for construction of underground structures and to the increase of the economic, social, and environmental benefits gained from use of the underground space made accessible. A large number of novel techniques are developed for geological survey, design, construction, and maintenance of the underground facilities. Their development is a consequence of the industrial revolutions. Therefore, such technology has exhibited distinctive industrial characteristics, e.g. mechanization, automation, digitization, and intellectualization. ICT has been widely used in practices, resulting in reliable and resilient underground structures. However, the involved scientific issues are just unfolding, due to a knowledge gap between the communities of scientists and engineers. This provides the motivation for this special issue to overview both the scientific developments and the engineering projects, related to ITC in the field of urban underground engineering. It is aimed to bridge the gap between the communities of scientists and engineers, identify the international frontiers of research, and convert the technology of practice into scientific achievements of human civilization. 

Concrete structural failures generally initiate with cracks. Effective control of cracks is the key to ensure the safety and durability of concrete structures. With the development of advanced sensing technology and bionic materials, more attention has been paid to the smart detection and healing for concrete cracks, which provides a new idea to improve the accuracy, efficiency and initiative of concrete crack control. This special issue focuses on the latest research theory and technology of smart detection and healing for concrete cracks.

3D Printing represents one of the emerging technologies in the age of digitization and intelligence. It has been drawing the attention of scientists in many fields, including civil engineering. The relevant research work in the field of civil engineering has been in progress since the 1990s and has made great progress during the past decade. Development of 3D printing concrete and concrete structures is challenging, because it involves interdisciplinary research, e.g., material science, structural engineering, mechanical engineering, automatic control engineering, information technology, software engineering, mechanics, physics, chemistry, mathematics, environmental engineering, etc. The main focuses of current research are on the material of printable concrete, the equipment for printing concrete, printed components and structures, and applications to large-scale structures. This technology exhibits promises in structural optimization, elaborate constructions reducing redundancy, and intelligent construction under extreme conditions. This Special Issue is planned to provide an overview of the frontiers of the development of 3D printing concrete and concrete structures. It is aimed to identify the knowledge barriers across disciplines, remove the barriers, and to promote the application of 3D printing technology in civil engineering.

The 10th International Bridge and Tunnel Technology Conference & “Belt and Road Initiative” Transport Infrastructure Forum was held in Shanghai, China on 13-14, September 2022. With the theme of Promoting Innovative Development and Building High-quality Projects, the conference focused on the development of China’s infrastructure construction since the 18th CPC Congress and the construction and management experience of Belt and Road Initiative transportation infrastructure. The conference contains quality academic reporting, strategic frontiers and topics discussion, excellent report collecting, tech innovation exhibition and major engineering tours, which make a thorough summary on the major achievement and experience of bridges, tunnels and other basic infrastructure in domestic transport, hydraulic engineering, municipal engineering, and national defense construction. More than 30 domestic and foreign academicians, 80 scholars attended the meeting online and offline and gave presentations.

In view of a number of high-quality presentations delivered at the conference, the suggestion of organizing a special issue on “Technology Developments in Bridge and Tunnel Technology” in Frontiers of Structural and Civil Engineering (FSCE) was proposed by both the organizer and participants, and was positively responded by Prof. Junzhi Cui, Editor-in-Chief of FSCE. This special issue features a total of 5 interesting and good quality papers. They papers are “Full-scale site evaluation of ventilation expressway embankments underlain by warm permafrost along the Gonghe−Yushu Expressway” by Wang et al., “Preparation, with graphene, of novel biomimetic self-healing microcapsules with high thermal stability and conductivity” by Wang et al., “An innovative structure of open ribbed steel-UHPC composite deck” by Sun et al., “Technology for tunnel construction through high-pressure and deeply buried super-high-temperature fault zones with large water surges” by Li et al., “Eigenfrequency analysis of bridges using a smartphone and a novel low-cost accelerometer prototype” by Xia et al. All papers were selected, revised, and eventually accepted for publication in this international journal by rigorous peer review. The Guest Editors of this special issue are grateful to the authors for their contributed papers and to the reviewers for providing good-quality and timely reviews.