MODERN BRIDGE ENGINEERING

The end of World War II in 1945, marked the beginning of modern engineering to IT technology and computer applications characterised, so far we’ve gone through the first six years. From the previously described six years about 60 innovations of modern engineering can be seen, and before the war compared to modern bridge technology has made a huge progress, including high-performance materials, finite element method and computer software, construction method innovation and large-scale automation equipment and other aspects of construction, showing a more sophisticated modern bridge design, construction and more high quality and high efficiency, conservation and management of monitoring techniques are increasingly sophisticated.

In the last decade of the 20th century, there are many international bridges are in 21st century conference theme. June 2006, the US Society of Civil Engineers (ASCE) held a “Future of Civil Engineering Summit” in Virginia Rand Youngstown City formed a prospect, “2025 Civil Engineering” report. The report calls for civil engineering counterparts around the world to work together to take action to create a more beautiful day for the early 21st century civil engineering.

Bridge project is an important branch of civil engineering, if we can follow the stages of modern civil engineering that: From 1945 to 1980, period is the foundation of modern bridge engineering; 1980 to 2010, period is progress, creating the 1950s to 1970s, many of the new technology has been fully applied and developed in the late sprint cross-sea engineering and 20 years in large-span bridges; in 2010, the modern bridge project will be matured in the turning point of this development, we also need Looking to bridge engineers operational goals for the next 20 years and important mission.

1.4.1 Bridge Engineer’s Mission and Mandate

“2025 Civil Engineering,” the report said: “Civil Engineers shoulders create a sustainable world and to improve the global quality of life sacred mission.” Therefore, “sustainable development” and “quality of life” is the 21st century, two important proposition, but also exposed the past 60 years the main issues and challenges faced. So the mission can be summarised as follows:

1. Bridge engineers are not only planners, designers and builders of the project, they should also be the lifetime operators and maintainers.

2. Bridge engineers should have the concept of sustainable development has become a protector of the natural environment and conservation of resources and energy advocates.

3. Bridge engineers should be involved in decision-making infrastructure, and construction of high quality and durable construction through continuous innovation, improve the quality of people’s lives become an active promoter.

4. Bridge engineer should become the project guardian against natural disasters, emergencies, accidents and other risks.

5. Finally, bridge engineers should also have team spirit and work ethic to become a model to resist all kinds of corruption performer.

1.4.2 Research and Development of Bridge Project

To achieve the above mission and mandate, bridge engineering must rely on the latest achievements of science and technology development, and through ongoing research and development work, and constantly improving existing technologies to create and invent more advanced technology to overcome shortcomings and resolve new issues to meet the greater challenges of the 21st century. Research focused on the following five areas:

1. Improvement of material properties is an important driving force behind the continuous progress of the bridge project. Modern steel and concrete bridge engineering is still the main building materials. Over the past six decades, the development of the steel from S343 to S1100, the development of concrete from C30 to C150, has made substantial progress. A variety of high-strength lightweight composite materials and smart materials have been used in bridge engineering. In the foreseeable future, nanotechnology and biotechnology may become an important driving force of technological innovation in the 21st century, and continue to enter the field of bridge engineering applications, has become a new generation of building materials carriers.

2. IT technology and improvement of computer processing power and the corresponding structural analysis software continues to progress, will make increasingly refined bridge design, to create the conditions for the realisation of numerical simulation and the “Virtual Reality” (VR) technology. Therefore, to carry out research of advanced theories and methods of conceptual design of bridge engineering, structural design, construction control, health monitoring, management and other aspects of conservation and development of appropriate software and database technology is a very important area of research.

3. Intelligent monitoring devices (sensors, diagnostic monitors, portable computers) and inventions of large intelligent robot construction equipment, will enable the construction, management, monitoring, maintenance and repair work of the bridge and a series of on-site automation and remote management. Our industry is still relatively backward equipment, heavy construction equipment, advanced testing equipment and sophisticated sensors are dependent on imports, we should vigorously carry out research and development work in this field of hardware, and gradually increase its investment in this regard, to get rid of external dependence.

4. Natural disasters and terrorist threats put high risk to the future world. National Natural Science Foundation of China’s recently launched a major research program on “major projects power disaster” will help reduce risk and ensure the safety of people’s lives, but also improve important aspects of people’s quality of life. In addition, the study of risk assessment and improve the structural durability should be taken seriously in order to ensure the normal life of major projects.

5. Finally, norms and standards to reflect an important indicator of the level of nation- building. In the allowable stress method (1923~1963), after which the limit state law (1963~2003), developed countries have begun working to develop performance- based design specifications (Performance-Based Design Code) in order to improve the level of infrastructure construction. The development of this new design is based on a full life and sustainable development of the concept of performance-based

design codes and standards, should be one of the most important tasks in the early 2000s to keep up with trends in the world of civil engineering development.

1.4.3 Bridge-building in the Era of Knowledge Economy

By the end of the 20th century, a new economic revolution quietly rose. In the 18th century Industrial Revolution two centuries later, with the information revolution as the core of the knowledge industry will bring a new era of human knowledge economy.

Era of knowledge economy is essentially an intelligent and efficient era. The development of modern communications technology makes highly information-oriented society, but also to family life, office, factory production, transportation, construction, education and training, health care, national management and other activities can take advantage of visual communication networks and multimedia, “information superhighway” automated and intelligent. Human intelligence and computer networks combine to make the knowledge innovation has become the most valuable products, a mainstay of the economy and the core of various industries.

Bridge construction in the era of knowledge economy will have the following characteristics:

1. In the planning and design phase of the bridge, people will use a highly developed computer-aided tools for effective rapid optimisation and simulation analysis, virtual reality application of technology so that the owners can be very realistic in advance to see the completion of the bridge after the appearance, function, and then simulate performance under earthquakes and typhoons, the impact on the environment and landscape day and night in order to decisions.

2. In the stage of manufacturing and erection of the bridge, people will use intelligent manufacturing systems complete the processing components in the plant, and then use the Global Positioning System (GPS) and remote control technology, thousands of miles away from the site outside the headquarters of the management and control of the bridge construction.

3. After the bridge is completed and delivered, by automatically monitoring and management system to ensure safe and proper operation of the bridge. Once a fault or damage, health diagnosis and expert system will automatically report the injury site and conservation countermeasures.

In short, in the knowledge economy era bridge engineering and other industries will have the intelligence, information and remote automatic control features. A variety of intelligent building robots managed by computer software under the control of the commanding officers at headquarters, the completion of underwater and aerial work under field conditions, precisely as planned bridge construction, it will be a 21st century bridge engineering magnificent sight.

By the end of 2007, the US National Academy of Engineering announced the approval by more than 50 experts in the “21st century 14 major engineering challenge project”, belonging to sustainable development, health, disaster prevention and improving the

quality of life in four areas. Which in addition to the health sector, and the remaining three are related and future bridge projects.

Looking into the modern engineering in the next 20 years, we should be fully understand the mission of bridge engineers and tasks in materials, software, hardware (construction equipment and monitoring equipment), disaster prevention and re-double their efforts to a new generation of standardised five aspects, greet challenges across the sea and island project for building and sustainable development in line with the concept of the whole life of the 21st century, modern bridge engineering our contribution. Finally, it should be noted that the invention of plastic in 1907, one hundred years has gradually developed into a new family of materials. Metal and mineral products have been a large number of high performance fiber reinforced plastic composites and replaced in the field of electrical appliances, medical equipment, automotive, aviation, agriculture, machinery and equipment, etc., and has been infiltrated with cement and steel as the basic material of the modern civil construction. After the near future (probably in 20 to 30 years later), engineering plastics and composite materials instead of cement and steel will gradually become the protagonist of building materials, playing the role of a landmark, which will be modern civil engineering (engineering) into modern new era, and caused revolutionary changes in design theory, system configuration, connection technology and construction method and the like.