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This study investigates the use of crushed glass waste as partial cement replacement in ordinary concretes. Six concrete mixes were designed and prepared: a reference without substitution and five substitution percentages of crushed glass waste ranging from 5% to 25%. The made concrete mix design underwent different tests, namely: slump test, mechanical strength, thermogravimetric analysis (TGA), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) determination and finally, water porosimetry, in order to evaluate the influence of the use of crushed glass waste on the properties of fresh and hardened concrete. Mechanical strengths results show that the use of 15% of the crushed glass waste improves the mechanical strength. TGA analysis confirms this result by highlighting a higher hydration degree. The latter contributes to the reduction of the porosity and, consequently, the mechanical strength increases. Also, it can be caused by the increasing amount of chromium which, if added a little, accelerates the hydration of C3S and leads to an increase of the mechanical strength. The BET technique and porosimetry tests showed that the use of crushed glass waste reduces the global porosity of concrete. This is due to the filling effect of the glass powder.

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The influence of the surface on the shape of' range distributions of ions implanted into solid matter was examined by TRIM computer simulations, with the intention to gain correction factors for analytic range codes (such as e.g. PRAL), as the latter ones yield informations about range distributions in infinite media only. It turns out that the surface influence is rather pronounced for low generalized energies E up to about 10'. Here. ranges and range stragglings are modified by up to about SO%, depending on the characteristic kinematic factor of' the examined system. Approximate fit formulae are given for this effect. The values of the third range profile moment, the skewness, are strongly modified by the surface influence in the E = 10'' to 10' regime in quite a complicated way. The forth moment (the kurtosis) is not modified markedly by the surface influence within its statistic accuracy. Finally, the backscattering yield is correlated with the ratio between the vacancies produced in an infinite and a finite medium, respectively, and with the corresponding ratio of range profile moments.