Joanna Julia Sokołowska

Waste Mineral Powders as a Components of Polymer-Cement Composites

The introduction of the sustainable development elements in the construction industry leads to finding new ways of using waste minerals that are difficult in storage and recycling. Coal combustion products have been already introduced into building materials as a part of cement or concrete but they have been thought insufficiently compatible with the polymer-cement binders [7]. The paper presents results of the mechanical properties of polymer-cement composites containing two types of mineral additives: waste perlite powder that is generated during the perlite expanding process, and calcium fly ash which is the byproduct of burning coal in conventional furnaces. Mechanical tests of polymer-cement composites modified with wastes were carried out after 28 and 90 days of curing. As a part of preliminary study specific surface area and particle size distribution of mineral wastes were determined.

Optimization of Polymer-Cement Coating Composition Using Material Model

The paper focuses on optimizing the elastic polymer-cement protection coating composition using material model. The material model consists of mathematical relations between composition and technical features demanded for protection, which are: flexibility, waterproofness and vapor permeability. The optimization that enabled obtaining the desirable values of features was proceeded by using statistical experimental design. Taking data from tests and choosing material variables, a material model based on quadratic functions was determined and in consequence three top rank compositions – each for a given feature – have been formulated. Evaluation of compositions was done using the desirability function approach. The individual desirability functions for the particular feature and the combined overall desirability function were treated as additional properties of the coating. Also, after defining the relation between desirability and composition, the overall desirability was enclosed in the material model as its generalization. High values of overall desirability confirmed the usefulness of compositions. The investigation proved that material models based on statistical methods are efficient tools for designing polymer-cement protective coatings.

Effect of Introducing Recycled Polymer Aggregate on the Properties of C-PC Composites

The subject of this paper is the evaluation of possibility of using the plastic waste fillers as the coarse aggregate of two Concrete-Polymer Composites (C-PC): polymer-cement concrete (PCC) and polymer concrete (PC). The applied fillers were crushed high density polypropylene (HDPP) wastes remaining after grinding plastic elements used in mountings and thermal insulation systems. The substitution of natural mineral coarse aggregate (river gravel) with plastic material was done on the various levels (0 ÷ 40% in case of PCC and 0 ÷ 100% in case of PC). For all composites the density, flexural strength and compressive strength were determined and compared with those for reference composites containing only the river gravel. The results enabled to indicate the levels of possible substitution of the natural aggregate, the non-renewable resource, with waste material, so that the properties of C-PC remain at the satisfactory level.

Influence of Acidic Environments on Cement and Polymer-Cement Concretes Degradation

Cement concrete is hardly considered as the acid resistant material however it should be possible to compare the ability of various cement based composites to resist the sever and chemically aggressive environments. The paper presents assessment of the resistance of cement concretes (of two types of mineral binders) as well as polymer-cement concretes (PCC) to hydrochloric acid. Due to the lack of proper standard procedures the tests were conducted according to the DBME own procedure: concrete specimens were exposed to acids of various concentrations and for various exposure times. The criteria for evaluation the concrete ability to resist the chemical attack were changes of mass, compressive and flexural strength. As PCC is considered to be a composite of better chemical tolerance it was treated as a kind of the reference material (chosen PCC characterized with similar compressive strength level as the previously introduced cement concretes). Approach used in the presented research enabled to compare different composites of similar compressive strength, the basic property to be taken into account in the design of the concrete and reinforced concrete structures.

The Influence of Specimen Shape and Size on the PCC Compressive Strength Values

The paper discusses the effect of the specimen shape and size on the result of compressive strength tests performed on polymer cement concrete (PCC). The shapes of tested specimens included cylinders and cubes of dimensions as recommended in EN-206 when determining the compressive strength class of cement concrete. Moreover, apart from cubes of standardized size of 150 mm, the research included tests of cubes of size 71 mm and 100 mm. The tests were performed on PCC with two different polymer aqueous dispersions: styrene-acrylic copolymer and carboxylated styrene-butadiene latex. As a reference, the tests were performed on the (polymer-less) ordinary concrete (OC). The results showed that the general rule – the smaller is the specimen, the higher values of strength it obtains – cannot be directly applied to PCC. Also the relation between compressive strength measured on cylinder and cube specimens (both for OC and PCC) did not show the conformity with reference ratios for OC.

Influence of Method of Preparation of PC Mortar with Waste Perlite Powder on Its Rheological Properties

The aim of this research is to determine the influence of waste perlite powder quantity on rheological properties of polymer–cement mortar mixture. Influence of dosing sequence of waste perlite powder on mortar mixture properties was especially taken into consideration. In the research, eight mortar mixtures were prepared using different quantities of perlite powder in mortar and by using different dosing sequence of mixture components. During the research, the influence of waste perlite powder on consistency and workability of mortar mixture was evaluated. By analyzing the various dosage sequences of the ingredients, the problem of difficult homogenization of the mortar and excessive dusting of the waste perlite powder were investigated. The obtained results show that changing the dosing moment of the key component – waste perlite powder – can influence technological properties of polymer–cement mortars.

Chemical Resistance of Vinyl-Ester Concrete with Waste Mineral Dust Remaining After Preparation of Aggregate for Asphalt Mixture

The aim of the research was to test the ability of vinyl-ester concrete containing waste powder to resist chemical attacks of sulfuric acid and sodium hydroxide. Tested composites contained mineral dust remaining after preparation of aggregates for mineral-asphalt composites. It was experimentally confirmed that from the point of view of chemical composition, granulometry, specific surface area, and density, the waste dust appeared to be a good substitute for commercial quartz powder used in polymer concrete. The evaluation of chemical resistance of polymer concrete with waste dust was done in terms of mass loss and change in compressive strength of composite after its exposition to aggressive media. The tests were performed according to the modified method described in guidelines for the precast elements production. Analysis of test results showed that even the high substitution of quartz powder with waste mineral dust (up to ~85%) in vinyl-ester concrete is possible and such composite presents high mechanical properties (though in some cases it requires using larger amounts of polymer) – not much worse than in case of non-modified composites.

Long-Term Investigation on the Compressive Strength of Polymer Concrete with Fly Ash

For the past years, a lot was said about the great potential of reuse of the fly ashes in the building materials industry. Fly ashes have gained recognition as a good addition to various concretes, including ordinary concrete, polymer cement concrete, and polymer concrete. Many research was conducted on the positive effect of fly ash on the technological and technical properties; however, most of them included tests performed after several days or weeks. Not much published data concerned tests conducted after a longer period of time, confirming the durability of polymer composites with fly ashes. The paper presents the results of compressive strength of polymer concretes with fly ashes tested after longer time. Composites with vinyl ester resin, standard sand, and fluidized fly ash were tested after 18 months, and composites with the same resin, river sand, and fluidized or siliceous fly ash were tested after 7 years. The results were compared with the results of the respective specimens tested after 14 days. Research results indicated that there was no reduction in compressive strength. Moreover, in all cases, a significant improvement of strength was noted. The research has demonstrated the usefulness of fly ash as a component for the production of durable polymer concrete.