Q1：During your trip in China, how many bridges have you been visited? What is your impression of China Bridges?
A1： I have visit 18 large bridge projects, mainly with long-span bridges. I addition completed 6 Lectures or seminars with fruitful technical discussion with Chinese bridge engineers and high level managers.
Q2: How do you think of the differences of bridges between China and Norway?
A2: There are many similarities in the bridge field between Norway and China, both design and construction methods. We also make use of the same type of bridges, and building materials except that Norway the previous two decades in addition has used glue laminated timber as bearing material in the superstructures, also for road bridges. I have only visited the western part of China, with all the big rivers, and of cause the incompact soil materials as foundation are I quite different from the rock along the Norwegian costal line where we mainly find our long-span bridges.
Q3: There was a peak buliding time in Norway when quantities of big bridges being built. Can you introduce us some background and stories of Norway’s leading period of bridge construction?
A3: Because of both economical & technical feasibility and requirements from society for an efficient road network, a number of large bridges were constructed to replace many ferry connections. Also experience from construction of large concrete oil production platform developed over knowledge, and contribute to realize this projects.
Q4: You have shown us a lot of beautiful pictures of the bridges in your country. How does most bridge in Norway ensuring bridge landscape effect. About Function and Athletics, how do you think of their relations?
A4: It becomes more and more important for the visual environment not only to think about a bridge function, but also its aesthetic value both for the society in general and also to fit and/or underline the landscape. Normally a team of bridge engineers decides the bridge type and its appearance, but in larger project we normally use both landscape architect and structural architects in our design teams. Sometimes, when we wish to design a signature bridge; we make use of an architectural competition and then choose the best idea, not only the most cost-effective.
Q5: In many countries, maintenance become increasely indispensible after the a great amount of bridges being bulit, please introduced your experience on bridge management and maintenance. In your opinion, what are the most difficulties and challenges?
A5: Owners, engineers and stakeholders must always bear in mind that large structure, despite a designed service life of 100 years, also needs management and maintenance after the construction completed to reach the expected service time. The need for major maintenance appears not the first years after they were built, but maybe after 20-30 years. The most complicate maintenance and repair works, are when it is detected comprehensive damage of concrete. It can be difficult to get funds for maintenance during service time, and preventive maintenance can often appear as a theoretical approach. If so, you get an increase maintenance backlog.
Q6: You mentioned Low LCC (life cycle cost) in your report, please talk about your opinion based upon this idea.
A6: Plan, design and construct new bridges correctly and with high quality and plan for long maintenance intervals. Think about consequences for traffic flow, ex. water protection layer, minimum of joints, “maintenance room” beneath deck and enough width of the bridge for both maintenance and traffic simultaneous. Also focus on minimal risk, ex. collision impact or damage caused by floods. And continuously update codes, guidelines and manuals when new knowledge or facts have been brought to light either by research and development or by long time experience. In the lead up to an OECD report in 1975, it was estimated that the yearly management, operational and maintenance costs ought to be about 1% of the bridge investment costs, as an average of the bridge stock.
Q7: In terms of Bridge construction and maintenance, what are the currently facing problems that should arouse universal attention?
A7: Durability of concrete, of cause including the reinforcement, and life time of different methods of repair methods. Especially when damage cause are chlorides from the sea water or de-icing salt on the road during winter time.
Cause of the very fast development of new infrastructure, you have many young graduates engineers, as told me - often an average age of 30-35 years in many planning and design groups. I hope that you have a good quality control, so that all the various details are as durable and technically robust as more experienced bridge engineers would have done it.
Q8: Send your word to the future of China Bridge development
A8: I am very impressed of planning, design and construction of all your large structures, especially long-span bridges in China. The large amount of major bridge projects, and, of course, all your long-span suspension and cable stayed bridges. As you probably know, is not the total length of the bridge, but the maximum span length that matter most to a bridge engineer’s heart.
Today, I mean that you now are the leading country in the world within planning, design of large bridges. It also seems that the Chinese engineers are aware of high quality, ex. through the use of high tensile strength of cables, high-strength concrete, epoxy coated rebar etc. As I see, it also looks like you’re paying attention to good workmanship and performance, e.g. smooth concrete surface finishing.