Intelligent Infrastructure

Structural engineering at the network level

Mission

Whereas traditionally the structural engineer conceives the single building or bridge as a self-standing project, the Intelligent Infrastructure group regards structures as cells that belong to a complex system – the civil infrastructure network. Recent advances in sensors and communication technology suggest that in a near future everything will be permanently connected to a distributed management network in such a way that owners, users, and in general, all those involved in the production/management process - connected via the Internet - can check the actual condition of structural elements during production, transportation, installation and operation. Design specifications, real-time operation, and any decision on maintenance, upgrading and reconstruction of the single cell will be the reflection of the management policy of the whole system, properly accounting for concepts as environmental impact and sustainability.

Research topics

The implementation of this vision involves development of cross-cutting research at different scale levels, from network to sensor, and involves, among other topics: infrastructure management, decision making, life-cycle risk evaluation; structural health monitoring and damage detection; communication and smart sensor technologies.

Bridge management. The primary objective of bridge management is to provide transportation agencies and highway operators with tools for the optimal allocation of economic resources, while maintaining an appropriate level of safety and serviceability of their bridge stock. Traditionally most bridge management is based on the qualitative evaluation of the condition through visual inspection. To overcome the limits of this approach, the group carries out research aimed to incorporate the concepts of risk and reliability into prioritization criteria, and to optimize the inspection, maintenance and repair strategy. This activity includes, on one side, search for of prioritization and management algorithms and, on the other, development of tools such us software and procedures, to make these concepts easily available to road operators.

Structural health monitoring. The radical developments that have taken place in the telecommunication and sensor technology fields are about to change the way that civil engineering design and infrastructure maintenance is conceived and carried out. Sensors and instrumentation for civil application presently used cost a fraction of what they used to cost ten years ago (and perform better) and the existence of embedded sensors from the initial construction will inevitably influence structural design and construction industry. The group activity in this field addressed different scale level: (1) development and integration of new sensors suitable for civil monitoring, including wireless sensors, fiber optics, electromagnetic gauges; (2) laboratory validation of new monitoring technologies; (3) design and deployment of monitoring system for real-time control and assessment of bridges and buildings.

Seismic vulnerability evaluation. We have learned from recent experience, including L’Aquila earthquake, how seismic action can seriously damage highway systems, even in those countries which are supposed to be prepared for such events. Therefore, there is the need to develop tools to predict possible damage scenarios resulting from a seismic event, in order to plan the reaction of those agencies, such as the civil protection, responsible for managing the post-earthquake emergency interventions. The group develops models and tools for incorporating seismic vulnerability analysis capability in bridge management systems. The work is based on the definition of the so-called ‘fragility curves’ for all the bridges inventoried, which represent the probability of structural damage given a specific design earthquake intensity. Apart from evaluating the direct seismic risk, involving structural collapse or loss of life, the vulnerability analysis allows to highlight critical problems in road network operation in a post-earthquake situation. The results can be used by decision makers to prepare a pre-earthquake plan, and for the post-earthquake emergency response. GIS tools are also developed to make the results directly available to those concerned (Figure 1).

Design of intelligent structural elements. The group carries out research and provide consultants to companies in the field of industrial design of prefabricated sensor systems and structural elements. This activity includes (1) support to prefabrication industry to design innovative model of structural elements (Figure 2); (2) development of prototypes of smart structural elements, incorporating sensing, computational and self-diagnosis capabilities (Figure 3).

Applications

Our research typically addresses owners and operators of large infrastructure networks (public transportation agencies, highway operators) as well as construction and high-tech industry. Recent applications include:

PAT Bridge Management System. Since 2003 our group have been working in cooperation with the Department of Transportation of the Autonomous Province of Trento (PAT) to develop a comprehensive Bridge Management System (BMS) that is currently operational. The APT-BMS is reliability-based and fully operative on the web (Figure 4). It includes: (1) an inventory section, which also serve as a repository for all the design information of the PAT’s bridges; (2) an inspection module, serving the owner to manage all the activity aimed at apprising the state of deterioration of the bridges; (3) a safety assessment module; and (4) a risk evaluation and prioritization section. Currently, PAT has inventoried in the BMS its full roadway bridge stock, consisting in more tha one thousand structures, and uses the system algorithms to optimize maintenance, repair and rehabilitation interventions and to state strategic intervention plans. Prioritization consider a number of risk sources (overload, structural deterioration, scour, substandard guardrails, earthquake), and allows the Department of Transportation to maximize the network safety while optimizing the budget. Access the website of the project at http://bms.heidi.it.

Seismic Vulnerability System. The group is currently involved, through Foundation EUCentre, in the development a seismic vulnerability management system for the National Civil Protection. This tool will provide the Civil Protection with: (1) an inventory of the national bridge stock and (2) with instruments to evaluate damage scenarios in the post-earthquake situation. Damage includes direct structural failure of bridges and loss in connectivity on segments of the national road network. The National Civil Protection is expected to use this tool to plan and manage the emergency interventions on the occurrence of an earthquake.

Adige Bridge monitoring project. The new cable stayed bridge on Adige River is the longest span in the Autonomous Province of Trento: it consists in a 260 m long stell-concrete composite deck supported by 12 steel cables (Figure 5). To investigate the long-term performances of the cables, and to early recognize possible abnormal states of the bridge, the group has designed and is involved in the installation of a pilot monitoring system, which includes high precision fiber optic elongation sensor and experimental models of magnetic-permeability sensors capable of direct detection of the stress state of the stays. The instrumentation is combined with a decision support system designed to deliver probabilistic damage information to the owner through the PAT’s BMS.

MEMSCON technology. Rapid advances in sensing and data transmission techniques, such as Radio Frequency Identification (RFID) technology, Micro-Electro-Mechanical Systems (MEMS), lower power wireless networking and in computation give hopes for a new generation of small, inexpensive, networked sensors that can be distributed on civil and building structures to provide accurate, quantitative information on the physical structure state while in service. The aim in EU-funded MEMSCON project is to develop MEMS-based sensors for construction monitoring and to integrate them with a Decision-Support-System (DSS) that will use the information from the above sensors to aid decisions on both proactive rehabilitation and on rehabilitation after earthquake damage in reinforced concrete buildings (Figure 6). See more at http://www.memscon.com.

Highlights

Among all, the innovation of the research carried out is demonstrated by the following facts:

  • The bridge management system developed for the Province of Trento is ranked among the word top 20 systems (and the only Italian one) listed by the Bridge Management Committee of the International Association for Bridge Maintenance and Safety.
  • Adige Bridge pilot project include one of few deployment worldwide of electromagnetic sensors on cable stays, and the first in Europe.
  • The group Materials and Structures Testing Laboratory is the second largest facility for pseudo-dynamics in Europe. The laboratory features a 9m-high L-shaped reaction wall and 1000kN hydraulic jacks, allowing simulating the effect of an earthquake on a full-scale 3-story building.

Funded research projects

  • Project title: "MEMSCON: Radio frequency identification tags linked to on board Micro-Electro-Mechanical Systems in a wireless, remote and intelligent monitoring and assessment system for the maintenance of constructed facilities." PI: D. Zonta. Source: European Commission. Period: 10/1/2008-9/31/2011. Amount: € 256,406 (€ 5,163,893 overall).
  • Project title: "BMS A&S: Structural monitoring of the Trento North-Rocchetta cable stayed bridge on Adige river." PIs: R. Zandonini and D. Zonta. Source: Autonomous Province of Trento, Department of Transportation. Period 10/20/2010-29/2/2012. Amount: € 108,000.
  • Project title: "PRIN 2007JHK33Y_002: New technologies for the real-time assessment of the seismic vulnerability of bridges." PI: D. Zonta. Source: Italian Ministry of Education (MIUR). Period: 9/20/2008-9/19/2010. Amount: € 62,900 (€ 250,000 overall).
  • Project title: "ADIGE: Structural monitoring of the Trento North-Rocchetta cable stayed bridge on Adige river." PIs: R. Zandonini and D. Zonta. Source: Autonomous Province of Trento, Department of Transportation. Period 6/1/2009-6/1/2012. Amount: € 108,000 (€ 300,000 overall).
  • Project title: "APT-BMS-6: Guided startup of the APT-BMS: support to the inspections on the Provincial Roads." PI: R. Zandonini. Source: Autonomous Province of Trento, Department of Transportation. Period 2/1/2007-3/11/2008. Amount: € 96,000.
  • Project title: "RELUIS: Reserch Line 10: New technologies for managing the seismic hazard in road infrastructure". PI: D. Zonta. Source: Italian Earthquake Engineering Laboratories Network (RELUIS). Period: 11/1/2005-10/31/2008. Amount: € 70,000.
  • Project title: "RIVOLI-1: Design of a new model of partially post-tensioned precast concrete box-girder element " PI: D. Zonta. Source: Rivoli SpA. Period: 4/1/2008-11/31/2008. Amount: € 12,500.

People

Faculty members

Postdoctoral reserchers

Doctoral Students

Selected publications

  • Pozzi M., Zonta D., Wang W., Chen G., "A framework for evaluating the impact of structural health monitoring on bridge management". Proc. "5th International Conf. on Bridge Maintenance, Safety and Management (IABMAS2010)", Philadelphia, 11-15 Jul, 2010.
  • Yue Y., Zonta D., Bortot F., Zandonini R., "Assessment of the operation level of a bridge network in post–earthquake scenarios". Proc. "5th International Conf. on Bridge Maintenance, Safety and Management (IABMAS2010)", Philadelphia, 11-15 Jul, 2010.
  • Zonta D., Pozzi M., Wu H., Inaudi D., “Bayesian Logic Applied to Damage Assessment of a Smart Precast Concrete Element”. Key engineering materials, 2009, v. 413-414, p. 351-358.
  • Zonta D., Bortot F., Zandonini R., "A condition index based on the concept of Apparent Age". In: Bridge Maintenance, Safety,Management, Life-Cycle Performance and Cost, Rotterdam:Balkema, 2008. Proc. "4th International Conf. on Bridge Maintenance, Safety and Management (IABMAS08)", Seoul, 13-17 Jul 2008.
  • Zonta D., Zandonini R., Bortot F., "A reliability-based bridge management concept". Structure and Infrastructure Engineering, 2007, v.3, n.3, p.215-235.

The group has published more than 70 technical papers on the topic in the last 5 year. See the website below for more information.

Contacts

Dott. Ing. Daniele Zonta
+39 0461 282537
daniele.zonta@ing.unitn.it
http://www.ing.unitn.it/~dzonta