Structures and Materials

Summary

PEC Structures and Materials research area focuses on applied and fundamental researches of the behavior of structures and the properties of construction materials ranging from conventional materials such as concrete and steel to new materials designed for specific structural functions. Those studies and researches aim at the fulfillment of safe and environmentally sustained civil works with high performance and cost-benefit advantages for the society.

Research activities in structures conducted since the beginning of the Civil Engineering Program in 1968 have worked up seeking to solve special problems found in the structural engineering practice. We can mention, for example analyses, projects and execution  of long span structures (cable-stayed bridges, cable structures, etc.), dams and other hydroelectric power plant structures, offshore structures, pipelines and risers, wells and oil refining units,  big machinery and equipment, industrial and multiple-floor buildings, besides other researches on repair, reinforce and structural restoration.

This research area comprises laboratory and field monitoring of structures aiming the identification of the main characteristics of structural behavior involving the study of the methods of static and dynamic experimental analyses of structures, signal and image processing techniques, vibration modal analysis techniques, methodologies for model updating, structural health monitoring and even the identification of eventual damages. This area also includes Physical Modeling of structures, allows reduced scale modeling of civil and offshore structures, according the Theory of Similarity, aiming a better understanding of the behavior of new concepts or even of structures that can not be monitored in real scale.

The analysis and design of civil structures under dynamic loadings are also included in this area as well as the development of strategies to control vibration at acceptable limits of structural safety and use, mainly considering human well-being.

Typically studied materials are those used in construction such as concrete, metals, polymeric composites, metal, polymeric and vegetal fiber cement composites, new types of high and ultra-high mechanical and environmental performance concretes, refractory concretes for oil refineries, micro-concretes used in oil well cementing, roller-compacted concretes, nanopowders for cement materials, besides new construction and repair materials. The laboratory, analytical and computational methodologies employed connect the materials with the structures performing analyses from the nanometric and micrometric scales to the mesoscopic scales of the test specimens and the macroscopic scales of the real structures.

Several studies have been performed based on numerical methods and high performance computational resources aiming at developing solutions for the analyses of structures and materials Simulation and optimization methods, data mining techniques, thermochemical mechanical coupling theory, dynamic structures, structural stability theory and structures under fire loads, among others.

The performance of materials and structures in relation to environmental sustainability is a concern in structures and materials research area, which is demonstrated on studies of civil works that demand lesser use of non-renewable raw materials focusing on higher durability and reduction of gas emissions that contribute for global warming.

Finally, it should be mentioned that research activities on structures and materials at PEC are strongly supported by the experimental and computational resources available at PEC’laboratory of structures located at block I2000 at the Technology Center, UFRJ. Within this environment, research activities are conducted by under-graduate and graduate students, professors and technicians.

Research Lines

Concrete, steel, mixed concrete-steel and composite materials structures

This Research Line seeks the analysis, design and stability and safety evaluation of systems and structural elements in concrete, steel, concrete-steel composites and fiber reinforced resins. Innovative concepts for structural projects and the use of new and conventional materials on structure recovery are included in this line.

Cementitious materials: experiments and modeling

This research line includes: (i) scientific dosage of conventional strength, high performance and ultra-high performance concretes; (ii) high temperature behavior; (iii) study of rheology; (iv) study of durability and slow strains; (v) computational  modeling of flow and transport in porous media; (vi) study of micro and nano-structural properties of concrete; (vii) study of sub-micro and nanometric particles and of nanofibers as concrete inclusions (viii) study of fibrous concrete with multiple cracks under direct tension, of reinforced fibrous concretes and textile composites; (ix)  development  of low environmental impact concretes and composites (see description in the environment research area); (x) study of special concretes for the oil industry (see description in the oil and gas research area); (xi) use of state-of-the-art techniques in numerical modeling and computational intelligence and (xii) micromechanical modeling.

Hydroelectric power plant and mass concrete structures

This research line includes: (i) experiments and thermo-chemo-mechanical modeling of the performance of early-age concrete (ii) high performance numerical modeling of hydroelectric power plant structures (iii) experiments and modeling of alkali aggregate reaction (AAR); (iv) scientific dosage of roller compacted concretes (RCC) (v) development of new materials for power stations and spillways (vi) use of computational intelligence techniques for dam safety.

Stability of structural systems

This Research Line focuses the development of mathematical methods and numerical and computational resources to analyze stability, non-linear behavior and sensitivity to defects and initial conditions of structural systems under pseudo-static and / or dynamic actions.

Structural dynamics and vibration control

This Research Line aims the theoretical and numerical development of tools to be used on the analysis and design of civil structures under dynamic loads. It also involves the development of strategies for vibration control at acceptable limits of structural safety and use, mainly focusing human well-being. This Research Line has a strong partnership with the Structure Identification Research Line, once the developed methods are assessed through experimental tests.

Structure and material numerical modeling

This Research Line seeks the study and development of classical numerical methods based on finite elements, boundary elements and finite differences. Linear and non-linear dynamic analyses required by the increasing challenges of modern engineering on structural concepts as far as the use of new materials are included.

Structure identification and physical modeling

This Research Line aims the development and implementation of methods to determine the dynamic behavior of the analyzed structural system. It comprises the study of methods of static and dynamic experimental analysis of structures, image and digital signals processing techniques, vibration modal analysis techniques, modal updating methodologies, structural health monitoring, and also the identification of eventual damages.

Continuous Mechanics

This research line seeks the study of stresses, deformations or flows arising in the interior of solids, liquids and gases. It proposes the development of formulations based on material (reference) or spatial descriptions of continuous media kinematics aiming to analyze problems in several engineering fields. Those analyses may be theoretical or numerical through discrete methods.