Mr. E. Polydorou
Room: CBER/EERC PGR Room 0G.312B
David Keir Building,
Queen’s University Belfast
Impact and blast resistant structures made with Ultra High Performance Fibre Reinforced Concrete (UHPFRC)
Supervisors: Prof. M. N. Soutsos, Dr. D. Robinson, Prof. J.F. Chen
Ultra high performance fibre reinforced concretes (UHPFRCs) which have been developed in an attempt to improve the mechanical performance of cementitious materials, especially strength and ductility under tension. The compressive strengths of Reactive Powder Concrete, one type of UHPFRC, are likely to be between 170 to 230 MPa depending on the post-set heat treatment (20 to 90oC). Values for flexural strengths are likely to be between 30 and 60 MPa, fracture energies between 20,000 and 40,000 J.m-2and moduli of elasticity between 50 to 60 GPa. RPC appears to be a promising new material not only because of its enhanced ductility but also because the mixing and casting procedures are no different to existing procedures for normal and high strength concretes. The project is aimed to supplement and develop existing expertise and data to permit reliable estimation of the behaviour of RPC under impact and explosion loading conditions. This will make use of state-of-the-art equipment, computer modelling techniques and software. Specific objectives include:
- Experimentally determine the mechanical properties, compressive and flexural strengths, fracture energies, moduli of elasticity, of RPC to provide accurate input data for the computer programs.
- Numerically and experimentally investigate the impact load resistance of RPC, with different reinforcement details.
- Develop guidelines for the design and detailing of RPC elements to resist impact and explosion loads.
- Develop computer simulation programs that will be able to provide accurate predictions of the behaviour of RPC under impact and explosion loading.
The Abaqus finite element analysis package will be used to undertake the computer simulation of the impact. The package will be used to perform an explicit transient dynamics analysis of the impact. The non-linear plasticity models available within the package will be used to capture the material characteristics of the UHPFRC material.
Master of Engineering (MEng), Civil and Structural Engineering, First class
2013, Institution of Structural Engineers Prize
2012, Mott MacDonald Design Prize
Ultra high performance fibre reinforced concrete (UHPFRC), fracture mechanics, structural dynamics, impact and blast resistant structures, finite element analysis, Abaqus
School of Planning Architecture and Civil Engineering
MEng in structural Engineering-Wuhan University of Technology, China
BEng in Civil Engineering-Hubei University of Technology, China
Multi-scale modelling of FRP-to-concrete bonded interfaces
This project will develop a multi-scale modelling approach to predict the interfacial bond behaviour between fiber reinforced polymer (FRP) composites and concrete. A mesomechanical model includes the explicit description of the heterogeneous material geometry close to the FRP-concrete interfacial zone will be proposed.
Damage and failure processes taking place at the mesoscale to the macroscale will be linked using a transition procedure by establishing a connection between formulations at the macroscale and mesoscale levels. This can be achieved through constructing base functions of macroscopic element numerically and then transferring mesoscale heterogeneous properties on the sub-grid to macroscale levels. This work will be chiefly numerical, using the commercial software ABAQUS.
A small number of small scale FRP-to-concrete tests will be conducted to validate the numerical models. The test will include load and strain measurements.
Prof Jian-Fei Chen, Prof Wei Sha, Prof Marios Soutsos
multi-scale modelling; fracture mechanics; finite element analysis, Abaqus