NGS-Concrete - New Generation Shielding Concrete against Ionizing Radiation - the Potential Evaluation and Preliminary Investigation

Abstract

Concrete is a common material used as a shielding against ionizing radiation due to the relatively low cost and the ability to meet the structural function. State of the art in concrete shielding is that while in case of gamma radiation an increase in density by a change of aggregate is usually efficient enough, protection against neutrons is more complex. It is due to the differences in interactions of neutrons with the matter, depending on their kinetic energy and reaction cross-sections with the component atoms of the cement paste and the aggregate. Last progress in concrete evolution due to use of polymer additives (e.g. superplasticizers) together with reactive additions (e.g. silica fume) allows for a new look at the concrete design for radiation shielding purposes. One of the main advantages of concrete is its composite-type and there is a potential for the optimization of its constituents as well as mixture proportions. The paper presents the preliminary results of the project NGS-Concrete -newgeneration shielding concrete against ionizing radiation. The aim of the project is to design the composition of concrete against ionizing radiation, achieved by the use of experiment based multi-criteria optimization of materials supported by the Monte Carlo simulations. The purpose of presented studies was to evaluate neutron shielding properties of ordinary and heavy-weight magnetite concrete modified with epoxy resin and gadolinium oxide. At first the shielding efficiency against neutrons from LWR neutron flux source and Pu-Be was simulated in MCNP code. At the end the comparison of MCNP simulated results and real experiment was presented. It was proved that both methods of modification can improve neutron shielding properties concrete but gadolinium oxide is an efficient additive only for low energy neutron attenuation.

Experiments on Neutron Transport through Concrete Member and the Potential for the Use in Material Investigation

“…The experimental results were in accordance to MCNP simulations made for the same geometry and conditions (Pu-Be source, helium neutron detector) as it was in the first experiment. The details of performed MCNP simulations are described in a study of Piotrowski et al [11]. It is proved by close values of linear attenuation coefficient -µ, half value layer -HVL and tenth value layer -TVL values (Table) calculated as follows [12,13]:…”

Ocena Efektywności Nowej Generacji Betonów Osłonowych Przed Promieniowaniem Jonizującym W Oparciu O Pomiary We Wzorcowych Polach Promieniowania

“…Również inne wymagania dla betonu zawarte w RCC-CW [4] znacznie wykraczają ponad standardowe wymagania dla betonu opisane w PN-EN 206, które przewidują jedynie 50 lat trwałości [2].…”

“…Dotychczasowe badania wskazują, iż optymalny skład betonu osłonowego przed promieniowaniem gamma jest inny niż betonu osłonowego przed promieniowaniem neutronowym [3][4]. Wynika to ze specyficznego oddziaływania neutronów z materią, w zależności od ich energii kinetycznej i tzw.…”

“…Wynika to z dosyć dużej powierzchni próbki która wynosi 1600 cm 2 oraz faktu, iż źródło promieniuje w sposób izotropowy. Prace obejmowały także skonfigurowanie systemu pomiarowego, w skład którego wchodziły dwie rekombinacyjne komory jonizacyjne typu REM 2.8 oraz GW2 [4]. Decyzja o wyborze ww.…”

Photon Shielding Features of Quarry Tuff

“…Another designed material, known as NGSconcrete, polymers and standard cements mortars have been studied in their shielding features [18,19]. In these studies, the half value layer and the ten value layer were evaluated.…”