Quality specifications for roadway bridges, standardization at a European level WG3 Technical Report Establishment of a Quality Control Plan September 2018 Impressum by boutik.pt ISBN: 978-86-7518-200-9 Editors / Authors R. Hajdin, M. Kušar, S. Mašović, P. Linneberg, J. Amado and N. Tanasić Close collaborators N. Ademović, C. Costa, M. Marić, J. Almeida, N. Galvão, S. Sein, M. Zanini and L. Pendergast GLOSSARY Observation It is a datum (i.e. piece of information) from a primary source, which may be acquired by human senses or by measuring/recording of some properties via adequate instruments. Observations can be qualitative i.e. only the absence or presence of a property is noted, or quantitative if a numerical value is coupled to the observed phenomenon by counting or measuring. The observation is a perception of human senses or data measured by instrument that is regarded as relevant within the context of the inquiry. Indicator It is something that shows what a situation is like. The “situation” depends on the context of an inquiry. The indicator can be qualitative (e.g. bad, good, etc.) or quantitative and is based on analysis of one or several ob- servations. Performance indicator (PI) Following the above definition, the “situation” is understood here as performance. The term performance indi- cator stems from economics and measures the success of an organization or of a particular activity (such as projects, programs and other initiatives) in which it engages. The application of this term to physical objects is coupled to their fitness for purpose. The performance indicator measures fitness for purpose of a physical object such as bridge or its element. Since the fitness for purpose (i.e. quality) can change over time, so does the value of a performance indicator. Maintenance interventions can also change the value of performance indicator and therefore the performance indicators of physical objects also mirror the performance of the agency responsible for their maintenance. It is obvious that bridge performance relates to safety and serviceability, but other perfor- mance criteria can be useful as well. Key performance indicators (KPIs) Generally, there is no clear distinction between PIs and KPIs. In this project, the KPIs relate to a whole bridge and are as follows: • Reliability is the probability that a bridge will be fit for purpose during its service life. It is the complement to the probability of structural failure (safety), operational failure (serviceability) or any other failure mode. • Availability is the proportion of time a bridge is open for service. It does not include failure-related service outages but the ones due to planned maintenance interventions. Alternatively, the Availability can be mea- sured as additional travel time due to an imposed traffic regime on bridge. • Safety is the situation of life and limb being protected from harm during the service life of a bridge. Loss of life and limb due to structural failure is not included by this definition (since it would overlap with the Reliability). • Economy is related to minimizing the long-term cost of maintenance activities over the service life of a bridge. Herein the user costs incurred due to detours and delays are not included. • Environment is related to minimizing the harm to environment during the service life of a bridge. Quality control plan The quality control plan specifies all activities and tools, needed to ensure quality requirements related to bridge performance aspects (e.g. safety, serviceability, etc.). It defines the extent and the interval of inspections or in- vestigations and data necessary to estimate key performance indicators and forecast their future development. Quality control plan also includes decision model that suggest maintenance action based on the forecast of key performance indicators. In this sense the quality control plan overlaps with the Strategic Asset Management Plan (SAMP) as defined in ISO 55000. Failure mode Failure modes are quasi-permanent or transient situations that violate code specifications or owner’s/ operator’s provisions. This includes but is not limited to overall bridge collapse. Some of these situations, e.g. Ultimate Limit State and Serviceability Limit State, are specified in bridge design. Due to slow (deterioration) and sudden (e.g. natural hazard) processes, damages may occur that result in additional failure modes. Finally, owners/operators may define situations (e.g. spalling, corrosion traces, etc.) that are regarded as failure modes since they might comprise public perception of safety. Vulnerable zones These are the segments and or elements of a bridge structure in which damages have the largest impact on safety and serviceability. One vulnerable zone may be related to several failure modes. Ontology A set of concepts and categories in a subject area or domain that shows their properties and the relations between them. In this report, the Entity Relationship Diagram is used to describe the ontology of the Quality control framework. Taxonomy A classification – in this case different bridge types and main girder cross-sections are classified according to construction material, static system and geometry. TABLE OF CONTENTS 1. Introduction .............................................................................................................................................8 1.1 The importance of the road infrastructure ....................................................................................................8 1.2 Growing traffic and traffic loads ......................................................................................................................9 1.3 Climate change .......................................................................................................................................................9 1.4 Decision-making for existing bridges .......................................................................................................... 10 2. Terms and concepts ............................................................................................................................. 10 2.1 Definition of quality ............................................................................................................................................. 10 2.2 Definition of quality control ............................................................................................................................ 10 3. Quality of road bridges ........................................................................................................................ 11 3.1 Design and construction – acceptance criteria ..........................................................................................11 3.2 Inspection and monitoring ................................................................................................................................11 3.3. Operation and maintenance ............................................................................................................................11 3.4 Key Performance Indicators for existing bridges ....................................................................................12 4. Damage processes ............................................................................................................................... 14 4.1 Gradual observable and non-observable Damage Processes ............................................................ 14 4.2 Sudden events – natural hazards .................................................................................................................. 16 5. Performance indicators and observations ....................................................................................... 17 5.1 Conceptual remarks .............................................................................................................................................17 5.2 Damage Processes and Observations ..........................................................................................................17 6. Performance assessment ................................................................................................................... 20 6.1 Current practice and its deficits .................................................................................................................... 20 6.2 Safety and serviceability of an undamaged structure ...........................................................................21 6.3 Reliability ................................................................................................................................................................22 6.4 Impact of observations - change from undamaged structure ..........................................................23 7. Quality Control framework .................................................................................................................27 7.1 General explanation of the Entity Relationship Diagram ......................................................................27 7.2 Vulnerable zones ................................................................................................................................................. 28 7.2.1 Conceptual weaknesses ................................................................................................................................28 7.2.2 Vulnerable zones related to the superstructure ................................................................................28