 Ευχαριστώ, Ζών, για την παραδοσία, που ήταν δύσκολο να δούμε ό,τι μπορούμε να κάνουμε και να προσπαθήσουμε ακόμα, αλλά νομίζω ότι η συναγράφηση με άλλες δημιουργές είναι πολύ σημαντικά να έρθουν με πρακτικές δημιουργές. Είχαμε σημαντική εξαιρεία με το άλλο προσπρόγεσμα που είχαμε στον Ρομπασμό της Τραξίας. Είχαμε να δημιουργήσουμε δημιουργές στο τελευταίο, οπότε είναι ένα σημαντικό δημιουργή. Οι δημιουργές θα είναι πρακτικές, θα είναι χρησιμοποιημένος για εξαιρεία, για πρακτικές εξαιρείες, οπότε είναι άλλο, δημιουργή εδώ. Υπάρχει δημιουργία, αυτό είναι πολύ ενδιαφέρον, υπάρχουν προσπρόγεσμα, αλλά οι δημιουργές είναι δημιουργές. Και Ιωάννη, δημιουργή εξαιρεία, που είχαμε δημιουργήσει τελευταία, και θα θέλω να μιλήσω also some other guidelines here. So I might speak a little bit longer than the previous speaker. If you don't like me, you might say yes and stop me. However, I will continue to the second slide. The outline of the presentation we have also with my colleagues here. I forgot of course to mention my two co-authors. They are from Prague, the one is here, the other is probably in Prague. Milan Holitski from Clarkner Institute and Mirek Sikora also from Clarkner Institute. He is here sitting in the second row. And while we are cooperating with the university, the technical university in Prague, and we thought we will prepare something together, we have put also these ideas and these reflections and this experience in eight, nine pages, and we will deliver this document to the working group leader. While an outline of this presentation is a short introduction to the problem, what are current standards on structural health monitoring, maybe some more as also mentioned before, some important issues on the contents of these standards, and some findings from several studies we had on the, let's say verification of the existing performance or the updating of the existing performance of structures dealing with offshore structures, which is as Michael Faber yesterday said, this was already started in the 80s, monitoring, updating of the performance of offshore structures, flood protection. We had yesterday a very nice poster by one colleague from Delft about the updating of the performance of levies in Holland, in the Netherlands, and also heritage structures where we also had some examples here. Well, and then some conclusions with respect to how we can continue in this working group. We have to reassess a structure, we have to assess the real performance of an existing structure. Why? Because we have deviations from the original design. Many times we have doubts about the safety. We have inspection results and they don't show what we expect. We have a lot of time, we have changes in use. We change, we use an existing industrial building as an office building, for example. So loads are changing. Also for the bridges we have seen that the loads are changing. We have a lifetime prolongation especially in bridge or offshore industry and also sometimes you measure deflections, you measure other things. So you have inadequate serviceability. You have a lot of issues which are, let's say, high, they have a large width. The typical question is what type of inspections are necessary in this occasion? What type of measurements shall be taken? And what analysis shall be performed? So we should also deal with these problems in the guidelines. But, of course, one last question which might be also dealt with is what is the future risk in using the structure and is this risk acceptable or not? Is this reliability acceptable or not? Is this risk, if we do risk-based, probably? Criteria, is this acceptable or not? If we are looking now to standards and I hope you are able to read it if you are in the back because it's important to be able to read things. Yes, this is something I'm trying always to do to make the presentation that everybody can follow. We have a lot of standards, not only the one which were presented before but we should look also to countries like Russia who have a complete standard on monitoring and inspection. We can use, of course, the several ISO standards which are related to existing structures to monitoring and so on. This is a good basis. We have a Canadian standard on structural health monitoring dealing with various points. And also we have an Austrian FOS standard. For example, we have also the association SAMCO which has a document on existing structures very similar to the JCSS document and a guideline on health monitoring, very useful documents which will help us looking at the contents to look what it is important, how can we produce a practical guideline in this framework. Also, of course, using the interaction with the other groups. The covered issues are first, which is important, is a classification of the monitoring. We can have a short monitoring as it was mentioned before or spot monitoring. We have seen that in examples, some load testing, some resistance testing. We have periodic monitoring. You monitor, for example, offshore structures during hurricanes in the Gulf of Mexico. You have also permanent monitoring and then other covered issues which are of importance at least in these documents which we have classified as important based on our short review, which we have to extend, is the sensor classification, performance of tests, treatment of data, very important data. We have a lot of data during the design phase for some structures during the transportation phase and also, of course, the operation phase. Damage identification is written in inspection, optimal inspection planning, aspects on inspection planning. These issues, I think, at least we think, we should deal with in our guidelines. If you look to documents, we all know that we have classification of structures based on consequence classes. This is not only in the Eurocode, this is in other codes and also in the German standard of the association of engineers, FAUDE, is called. It's similar to the Eurocode, but what it is interesting, according to the classification, you have three consequence classes, everybody knows that, CC1 to CC3, but they have also a classification of what type inspection should be done based on what class of structures or on what consequence class you have. So you have a simple visual check where you go and check the structures, you have an inspection by an engineer and you may have a verification by an expert and you see here the time intervals, of course they are smaller shorter if you have an important structure, a CC3 structure, a high-rise building or a very important bridge and these are typical elements in such guidelines with respect to monitoring as we mentioned before. Our industrial experience here with my colleagues in Prague, they cover many cases. I'm also not very young. I was here in my first research fellowship in this university in the year 81 and I was working with Madsen and Dietlefsen. So you may understand that some experience in various types of structures has been accumulated offshore structures bridges with different types of, let's say, actions like waves, wind fatigue for offshore structures, fatigue in bridges, flood and earthquake for dams, heritage structures, live load, wind load, tunnels, fire, because you can have also detection of, you can have monitoring of detection systems in tunnels or also of the resistance of fiber reinforced short grid buildings, live loads, no load and earthquake. We have seen many examples in previous speeches. I would like to present very shortly some of the three typical of them, fatigue, steel jacket structures is a typical type of structure offshore structure with different yardsticks like fatigue, corrosion, marine growth, scour, stiffness against impact and air gap. We have data from the design phase to the installation phase to the operation phase so the organization of all this data together with the monitoring data is important because if you see at the data management you have the design phase data, the field data, the geotechnical data, you have the structural model, the geometry data, you have the drawings, then you have the installation phase for offshore structures also important because you might get damages there which can propagate during the operation phase and the situation can become worse. You have the operation phase where you have modifications, you have monitoring of displacement stresses, you have environmental monitoring of the data, you have cathodic protection data and so on so there is a lot of data and the management of this data at least should be reflected in such guidelines. At the end what the engineer of course has to take some responsibility so we are reflecting industrial cases where as an engineer you have to take responsibility, you have to tell to the owner of the platform it can be shell, it can be agile but they want to see when should I do what type of inspection and of course some let's say results like redistribution and reduction of deck loads if necessary, periodical cleaning of the marine growth which is changing the dynamic behavior of the structure, extensive long term inspection planning and in what time intervals inspection campaigns on critical nodes which are the critical nodes where we have do extensive inspection at reduced time intervals. Of course another problem is that we monitor as I said before when I ask this young lady we monitor you have 50 platforms so you cannot do extensive inspection on 50 platforms, you select two, three typical which are and then you have to extract the result to correlation analysis to other platforms. So this is also another question if we should deal with that problem. In Bavaria we had also snow loading as you said on roofs yesterday very interesting on the study in Bavaria we had roofs which have failed and not only the snow height is important but also the snow loads simply monitoring system is this so called snow load pillow you can see you can measure it's 1.4 meters the weight of the snow load flat it's also important there is coming the cooperation with Prague you see here we had in Prague the highest flat in the Flata river in the year 2002 in 200 years collapses of buildings based on flooding and let's say failure of the foundation considerable damage so we see environmental monitoring of environmental actions modeling of these environmental actions here the extreme event so we have continuous monitoring not exactly of the resistance of the structure of the health of the structure but of environmental parameters which influence the health of the structure which is also very important aspect to be dealt with in a clear let's say in a clear situation and you can see here what measures also in Regensburg in the city where we have the Danube river we have similar floodings and also similar levy constructions as they have been presented yesterday for the Netherlands a last example just to show you it's a very simple thing we have here a heritage structure where the critical structural member is an iron truss και an older truss it is 100 years old construction which will be used as an industrial building which will be used now as a publishing house as an office building and the case studies have shown the development of the probabilistic model for the iron strength it's a so called monitoring of the static strength according to the classification in the guidelines I mentioned before and also the satisfactory past performance is also a criterion to update reliability here you can see the updating very simple one of the steel strength and the 5% fractile value then you can this is based on simple Brineltes but you can also take out and test specimen you can have an additional by Asian updating importantly is also to consider the model uncertainties in such simple monitoring procedures well we were thinking about this project and we were studying also the contents and the proposal so personally I am very much interested in guidelines and looking also at experience we had in developing guidelines developing guidelines in the last 20-30 years our conclusions are the following well first the required information to be obtained by structural health monitoring needs to be clearly specified this is a clear thing you have to know what to do and how to use it this was mentioned before yesterday sometimes the present standardized approaches they provide limited sufficient guidance for planning the structural health monitoring and they need they are different if you let's say study the ISO document, the Canadian document the Russian document and the German document they are not very harmonized we have to also the experience from these cases have shown that the structural reliability with respect to ultimate limit states in some cases improved by looking at cracks for example or at other type of structure damage and one other aspect which has been dealt with which must be dealt with is also the global performance of the structure we had some interesting presentations with respect to system reliability of platforms and so on so we have to deal that also when you do the monitoring what kind of parameters are you actually measuring they influence the global behavior of the structure especially with respect to earthquake further conclusions, further improvements should primarily be focused on use of SHM results to assess similar but not monitor structures we have a group of structures we don't have money to inspect or to monitoring all of them and we use models to get conclusions for the rest of the structures also focusing on identifying value of updating of real performance as a basis for a future cost optimal maintenance plans is important developing of operational methods for updating procedures and also this could be also maybe connected to the new isonome which John mentioned before with respect to risk reliability acceptance criteria or use of new verification partial safety factors we will see the recommendations should also indicate appropriate methods to be applied critical structural members and cross sections which should be and how they should be selected they should be monitored optimal frequency of collecting data considering an observed failure mode and progress of degradation process threshold values for the observed values is also important of course and implementation of updating methods including measurement errors and model errors well we try to summarize some aspects which can be useful of course we are in the beginning as you said we cannot start with the guidelines and then force the people to do the models we start we we have time to do what is good to interact with the other groups we close here with two nice bridges it's the most known is the one in Prague the Charles bridge but the older one is the stone bridge it is the stone bridge is actually monitor and you see here some let's say measures here some protection measures against the water flow and also the cracks are monitor and so on so I thank you very much for the opportunity to be here and give this short presentation and yes if you have any discussion necessity of course we are here