Background and Objective

Aircraft impact is an external hazard that needs to be considered in the structural design and safety assessment of nuclear facilities. The structural response depends not only on the aircraft mass and impact velocity, but also on the resulting force-time history, impact duration, impulse, impact area and dynamic characteristics of the impacted structure. Representative aircraft impact scenarios can therefore produce significantly different local and global structural responses.

The objective of this Master’s thesis is to numerically investigate the structural response of the AirPlane Crash (APC) envelope of an SMR-LFR subjected to aircraft impact.

A nonlinear finite element model of the reinforced-concrete APC structure will be developed and subjected to representative aircraft impact load-time functions. Different aircraft categories, impact velocities, force-time histories and associated impulses will be investigated to evaluate their influence on the structural response.

The work will be performed considering the relevant provisions of RCC-CW, with particular attention to the treatment of impact and impulsive loading and the assessment of local and global structural behaviour.

Main activities

The Master’s thesis will include:

• Review of the relevant RCC-CW provisions for aircraft impact, impact loading and impulsive loading of nuclear civil structures.
• Review and selection of representative aircraft impact scenarios and load-time functions.
• Definition of the main impact parameters, including aircraft mass, impact velocity, impact area, force-time history, impact duration, peak impact force, total impulse.
• Development of a nonlinear finite element model representative of the reinforced-concrete APC envelope.
• Definition of appropriate material models and dynamic properties for reinforced concrete and reinforcement.
• Application of representative aircraft force-time histories to the APC model.
• Investigation of different aircraft categories and impact conditions.
• Parametric assessment of the influence of impact velocity, load amplitude, duration and impulse.
• Evaluation of the local and global dynamic response of the APC, including relevant quantities such as displacements, accelerations, internal forces, stresses/strains and structural damage.
• Comparison of the numerical results and modelling assumptions with the applicable RCC-CW provisions and acceptance criteria.
• Identification of the governing parameters and assessment of the applicability and potential limitations of the adopted numerical methodology.

The distinction between aircraft categories and the use of representative load-time functions are also consistent with the Belgian aircraft-crash assessment approach, which characterizes representative events in terms of aircraft mass, impact area, velocity and load-time function.

Student profile

The thesis is intended for a student enrolled in a Master’s-level Civil Engineering programme.