Influence of Polymer Modification on the Microstructure of Shielding Concrete

Abstract

In this paper an analysis of the influence of polymer modification on the microstructure, shielding properties against neutrons, and compressive strength of heavy-weight magnetite concrete is carried out. The modifications involve the addition of acrylic or epoxy dispersions as well as micro- or/and macrofibers. A computer image analysis method is used to evaluate the microstructure of concretes and parameters of pore structure are calculated; these parameters include relative volume fraction, relative specific surface area, and pore arrangement ratios, including a proprietary ratio based on Voronoi tessellation. An assessment of significance of differences between stereological parameters of reference concrete and polymer modified concretes, as well as the impact of polymer form (dispersion or fibers) on shielding properties and compressive strength is carried out using Student’s t-test. The results show that except for the effect of the addition of both polypropylene micro- and macrofibers on the relative volume of pores, all other modifications result in statistically significant changes in the values of stereological parameters. Nevertheless, it is shown that neither polymer dispersions nor fibers have a statistically significant impact on shielding properties, but that they do influence compressive strength.

Characteristics of Recycled Polypropylene Fibers as an Addition to Concrete Fabrication Based on Portland Cement

“…Concrete plays an important role in the process of recycling waste materials [21,22], especially plastic waste, in construction. Plastic waste can be used in concrete as an aggregate (aggregate in concrete or asphalt concrete, synthetic aggregate or as a binder in concrete by melting), resin in polymer concrete, synthetic agent or powder and as synthetic fibers [23][24][25]. According to Czarnecki [26], replacing virgin polymer fibers with recycled waste plastic fibers seems to be becoming a standard development.…”

Influence of the Type of Cement on the Action of the Admixture Containing Aluminum Powder

“…12 min from cement contact with water and additionally for CEM III 1.0% and CEM III 1.5% after 30 and 45 min from cement contact with water. For hardened mortars: Pore structure was evaluated by the computer image analysis method; the stereological method used for the quantitative description of three-dimensional phases in a material volume based on measurements performed on two-dimensional images of a material microstructure (images of sample cross-sections) [ 28 , 29 ]. The procedure of sample preparation for microstructure studies involved (1) cutting out one slice about 40 mm × 40 mm × 10 mm in size from a 40 mm × 40 mm × 160 mm sample for each concrete, (2) cold mounting under lowered pressure using a colored epoxy resin, (3) grinding, and (4) final polishing.…”

Concrete Strengthening by Introducing Polymer-Based Additives into the Cement Matrix—A Mini Review

“…The incorporation of polymer into the cementitious matrix changes the microstructure of concrete [ 94 ]. The impact of polymer addition on the cement hydration process was thoroughly investigated in recent years.…”