The Weldability of Duplex Stainless-Steel in Structural Components to Withstand Corrosive Marine Environments

There is still a considerable gap in the definition of the weldability of Duplex Stainless Steel (DSS). A lack of clarity that is explained by the standard specification of the maximum content of equivalent carbon that defines a “weldable” steel coupled with the fact that the alloying elements of DSS exceed this defined limit of weldability. In this paper, welding quality in an inert environment and in presence of chlorides is analyzed with the aim of defining optimum welding conditions of 2001, 2304, and 2205 DSS. The same procedure is followed for a hybrid weld between DSS 2205 and a low carbon mild steel, S275JR. As main output, this study defined the optimal welding conditions with tungsten inert gas without filler for each type of DSS weld that showed excellent anti-corrosion performance, with the exception of the DSS 2205-S275JR weld where widespread corrosion was observed. Additionally, this study established a relationship between the thermal input during welding and the content of alloying elements in defect-free joints. Furthermore, it demonstrated that an increase in ferrite content did not lead to a worse corrosion resistance, as expected after passivation.Center for the Development of Industrial Technology (CDTI) and the Technological Fund, part of the Spanish Ministry of Industry, through the INNPRONTA research program. UPV/EHU PPGA19/61 contract as well as to the IT1314-19 (Basque Government) and GIU19/029 (UPV/EHU) research groups and to Laboratoire des ciencies de l’ingenieur appliquées, Fédération IPRA-EA4581, from the Université de Pau et Pays de l’Adour, for their support setting a cooperation framework. Finally, we are also especially thankful to ACERINOX EUROPA (part of the ACERINOX Group

Improving the Resilience of Historic Areas Coping with Natural and Climate Change Hazards: Interventions Based on Multi-Criteria Methodology

Cultural and Natural Heritage (CNH), a legacy bequeathed to present and future generations, casts light on the humanity of past generations. However, the increase and the intensity of natural and climate-change-related hazards threaten the conservation of such heritage. The aim of this research is to develop a multi-criteria prioritization methodology in support of intervention decisions, to enhance the resilience of CNH conservation through sustainable development. The application of two methods, the Integrated Value Model for Sustainability Assessment and the Analytical Hierarchy Process, ensures both the contribution of a wide panel of experts of heritage conservation and equitable indicator assessment measured on different scales. The prioritization methodology has been developed considering the most common hazards and specific disaster-risk scenarios. The three dimensions of sustainable development and both technical and cultural dimensions are also considered in the methodology. All dimensions and their indicators are weighted to produce a Prioritization Index to support decision-making.The authors wish to acknowledge funding received from the European Commission through the SHELTER project (GA 821282) and, especially to the contribution of the University of Bologna, Tecnalia Research and Innovation, and EKOU. Additionally, the authors are thankful for the funding received from the SAREN Research Group (IT1619-22, Basque Government)

Urban Heat Islands and Thermal Comfort: A Case Study of Zorrotzaurre Island in Bilbao

This study assesses the impact of a heat wave on the thermal comfort of an unconstructed area: the North Zone of the Island of Zorrotzaurre (Bilbao, Spain). In this study, the impact of urban planning as proposed in the master plan on thermal comfort is modeled using the ENVI-met program. Likewise, the question of whether the urbanistic proposals are designed to create more resilient urban environments is analyzed in the face of increasingly frequent extreme weather events, especially heat waves. The study is centered on the analysis of temperature variables (air temperature and average radiant temperature) as well as wind speed and relative humidity. This was completed with the parameters of thermal comfort, the physiological equivalent temperature (PET) and the Universal Temperature Climate Index (UTCI) for the hours of the maximum and minimum daily temperatures. The results demonstrated the viability of analyzing thermal comfort through simulations with the ENVI-met program in order to analyze the behavior of urban spaces in various climate scenarios.This research was funded by research group IT1314-19 of the Basque Government

The Weldability of Duplex Stainless-Steel in Structural Components to Withstand Corrosive Marine Environments

There is still a considerable gap in the definition of the weldability of Duplex Stainless Steel (DSS). A lack of clarity that is explained by the standard specification of the maximum content of equivalent carbon that defines a “weldable” steel coupled with the fact that the alloying elements of DSS exceed this defined limit of weldability. In this paper, welding quality in an inert environment and in presence of chlorides is analyzed with the aim of defining optimum welding conditions of 2001, 2304, and 2205 DSS. The same procedure is followed for a hybrid weld between DSS 2205 and a low carbon mild steel, S275JR. As main output, this study defined the optimal welding conditions with tungsten inert gas without filler for each type of DSS weld that showed excellent anti-corrosion performance, with the exception of the DSS 2205-S275JR weld where widespread corrosion was observed. Additionally, this study established a relationship between the thermal input during welding and the content of alloying elements in defect-free joints. Furthermore, it demonstrated that an increase in ferrite content did not lead to a worse corrosion resistance, as expected after passivation.This research was funded by ACERINOX EUROPA through Center for the Development of Industrial Technology (CDTI) within the frame of IISIS project, grant number IPT-20111023

Corrosion Fatigue Numerical Model for Austenitic and Lean-Duplex Stainless-Steel Rebars Exposed to Marine Environments

Steel rebars of structures exposed to cyclic loadings and marine environments su_er an accelerated deterioration process by corrosion fatigue, causing catastrophic failure before service life ends. Hence, stainless steel rebars have been emerging as a way of mitigating pitting corrosion contribution to fatigue, despite the increased cost. The present study proposes a corrosion fatigue semiempirical model. Di_erent samples of rebars made of carbon steel, 304L austenitic (ASS), 316L ASS, 2205 duplex (DSS), 2304 lean duplex stainless steels (LDSS), and 2001 LDSS have been embedded in concrete and exposed to a tidal marine environment for 6 months. Corrosion rates of each steel rebar have been obtained from direct measurement and, considering rebar standard requirements for fatigue and fracture mechanics, an iterative numerical model has been developed to derive the cycles to failure for each stress range level. The model resulted in a corrosion pushing factor for each material, able to be used as an accelerating coe_cient for the Palmgren-Miner linear rule and as a performance indicator. Carbon steel showed the worst performance, while 2001 LDSS performed 1.5 times better with the best cost-performance ratio, and finally 2205 DSS performed 1.5 times better than 2001 LDSS.The authors would like to acknowledge funding support from Centre for Industrial Technological Development CDTI and ACERINOX EUROPA, that funded the materials and experiments through the grant of IISIS project: IPT-20111023 and UPV/EHU PPGA19/61 contract. Besides, they would also like to acknowledge the University of Akron, Fellowship Program FRC-207367, the IT1314-19 (Basque Government) and GIU19/029 (UPV/EHU) research groupsand the Laboratoire des ciencies de l’ingenieur appliquées, Fédération IPRA-EA4581, from the Université de Pau et Pays de l’Adour, for their support setting a cooperation framework for this research

Second-order fatigue of intrinsic mean stress under random loadings

A fatigue process due to random loading that is progressively damaging a certain structural detail will vary in the presence of mean stresses. The variations are already considered in crack propagation laws and by applying equivalent 0-mean stress ranges from the Palmgren–Miner linear rule. Nevertheless, if the mean stress is intrinsic, instead of a direct consequence of the random loading, other second-order effects will have to be taken into account. Those effects are cycle quasi-ordering, histogram variations, and apparent mean tension, which are identified and defined in this study and, finally, developed in a case study for demonstrative purposes

Improving the Resilience of Historic Areas Coping with Natural and Climate Change Hazards: Interventions Based on Multi-Criteria Methodology

Publisher Copyright: © 2023 The Author(s). Published with license by Taylor & Francis Group, LLC.Cultural and Natural Heritage (CNH), a legacy bequeathed to present and future generations, casts light on the humanity of past generations. However, the increase and the intensity of natural and climate-change-related hazards threaten the conservation of such heritage. The aim of this research is to develop a multi-criteria prioritization methodology in support of intervention decisions, to enhance the resilience of CNH conservation through sustainable development. The application of two methods, the Integrated Value Model for Sustainability Assessment and the Analytical Hierarchy Process, ensures both the contribution of a wide panel of experts of heritage conservation and equitable indicator assessment measured on different scales. The prioritization methodology has been developed considering the most common hazards and specific disaster-risk scenarios. The three dimensions of sustainable development and both technical and cultural dimensions are also considered in the methodology. All dimensions and their indicators are weighted to produce a Prioritization Index to support decision-making.The authors wish to acknowledge funding received from the European Commission through the SHELTER project (GA 821282) and, especially to the contribution of the University of Bologna, Tecnalia Research and Innovation, and EKOU. Additionally, the authors are thankful for the funding received from the SAREN Research Group (IT1619-22, Basque Government).Peer reviewe

Previous studies in a singular bridgeBridge of Almarail in Soria

Peer reviewe

Damage assessment and conservation strategy for the largest covered market in Europe: the Ribera Market (Bilbao)

Publisher Copyright: © 2018, © 2018 Taylor & Francis.Facing a scarcity of land for urban development and demand for public services, the Municipal Council of Bilbao recognizes the need to make good use of its built heritage and to upgrade it, while maintaining its cultural and functional features. A good example is the case of the Ribera Market, the largest covered market in Europe. Deterioration of the market building and public pressure for improved services has led to proposals for its rehabilitation. To do so, the constructive condition of the building must first of all be assessed and, then, the most appropriate and compatible intervention technique must be selected. Today, there is a broad selection of intervention technologies, for the improvement of both mechanical behaviour and durability. However, in this article, it is demonstrated that these technologies are not always applicable in old buildings, because they depend on the severity of the pathology and the intrinsic characteristics of the building: for example, corrosion due to chloride ions originating from the concrete mass. The lack of knowledge on constructive techniques and the requirements for the application of new technologies complicate the interventions, which in turn further complicates decision-making with regard to the property.We express our gratitude to the Basque Regional Government (IT781-13 research group). This research work has been made possible thanks to the support received from the Municipality of Bilbao and Tecnalia Sustainable Construction Division.Peer reviewe

The Risk of Heat Waves to Historic Urban Areas. A GIS-Based Model for Developing a Risk Assessment Methodology

Publisher Copyright: © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.Climate change impacts such as extreme events and progressive global warming are threatening the conservation and livability of urban cultural heritage. Understanding climate risks on heritage should be part of policy and planning decision-making processes to increase resilience and sustainability of both social and built environmental systems. However, despite a large body of literature focusing on climate-related hazards, there is a noticeable knowledge gap regarding a holistic conceptualization of the risks in historic urban areas, which is particularly concerning in the case of the impacts of heat waves and heat urban island phenomena on urban heritage. The main goal of this study is to analyze and represent the interaction between urban spaces and heat waves via geographic information systems (GIS) data, considering the vulnerability of historic areas both as urban systems and as heritage areas. To frame a holistic approach, socioeconomic, cultural, governance (services and resources), and physical (gathering tangible characteristics of all infrastructures, elements, and buildings) aspects of the system are taken into account. To this end, key performance indicators addressing relevant vulnerable elements of historic urban areas are identified for the development of a risk assessment methodology. Complementary and as foundation for the risk assessment, a categorization of vulnerability to heat waves is proposed for both buildings and urban spaces. Here, the gathering and processing of data for the development of a GIS-based model in the historic area of Bilbao, Basque Country is presented. This work aims to serve as a basis and reference for future holistic assessments of heatwaves risks in historic urban areas worldwide.Acknowledgements The authors wish to acknowledge funding from the European Commission through the SHELTER project (GA 821282), as well as the support of the SAREN research group (IT1619-22, Basque Government).Peer reviewe