Grzegorz Adamczewski

UIR-Scanner Potential to Defect Detection in Concrete

In the research three NDT methods: indirect Ultrasonic Pulse Velocity, Impact-Echo (IE) and Ground Penetrating Radar (GPR) were used for investigation of concrete slabs with well-defined reinforcement and artificial defects. The obtained results shows the big potential of combination of UPE, IE and GPR methods for detection of wide range of defects in concrete structures. These methods were implemented for UIR scanner development – NDT system which accelerate assessment of concrete structure. Moreover, when the result of one method is not clear and individually the method seems to be not effective, the data from the other one allows for proper interpretation of concrete integrity.

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.

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.