Magdalena Rajczakowska

• Doctor of Engineering
• PostDoc Position at Luleå University of Technology

Developing accurate and interpretable models to forecast concrete’s self-healing behavior is of interest to material engineers, scientists, and civil engineering contractors. Machine learning (ML) and artificial intelligence are powerful tools that allow constructing high-precision predictions, yet often considered “black box” methods due to their...

Autogenous self-healing of post-fire damaged concrete enables structure performance auto-recovery leading to reduced repair costs, less generated waste, and lower CO2 emissions. In this paper, to improve the efficiency of this process and understand the underlying mechanism, the self-healing of 0.1 wt% MWCNT-modified and pure cement paste subjected...

In recent years, substantial progress has been achieved in the development of multifunctional cement-based composites, targeting improved energy efficiency and environmental sustainability while minimizing material depletion. Leveraging the high thermal capacity of these materials facilitates controlled heat storage and release, providing versatile...

Concrete has emerged as a promising solid-based sensible heat storage (SHS) material due to its favorable balance of thermal properties, cost-effectiveness, non-toxicity, and widespread availability. This state-of-the-art review examines the applications of concrete-based SHS across diverse domains, including buildings, concentrated solar power sys...

The growing demand for renewable energy has increased the use of offshore wind turbines, requiring sturdy infrastructure. However, environmental challenges impact not only the turbine components but also the foundations in the water. Different foundation structures exist for varying sea-bed conditions, each with material durability pros and cons. C...

This manuscript presents preliminary results on the cement paste potential, with and without carbon nanomaterials, to heal high-temperature cracks. Cement paste beams were subjected to thermal loading of 200°C and 400°C after 28 days of water curing. High temperature caused the formation of microcrack networks on the specimen’s surface. Self-healin...

Concrete structures exposed to harsh environments, especially including bridges, harbor structures are often suffered from durability problems. Typical external signs include surface deterioration, cracking caused by for example sulphate attack, frost action or reinforcement corrosion. All are strongly linked to the porous microstructure of the bin...

Cement paste is the matrix of one of the most widely used building material in the world, i.e., concrete. Cement production is estimated to account for 8% of global CO2 emissions. Thus, the impact of cement composites on the environment is enormous. Scientists are conducting research to reduce this negative environmental effect by using materials w...

The construction of the future is moving in the direction of environmentally friendly materials and the use of various types of industrial byproducts and wastes. The use of blast furnace slag (BFS) for the production of concrete is one of those alternatives. In this study, pastes and concretes based on high-MgO BFS were alkali activated with 10% by...

A reduced carbon footprint and longer service life of structures are major aspects of circular economy with respect to civil engineering. The aim of the research was to evaluate the interfacial bond properties between a deteriorated normal strength concrete structure and a thin overlay made of Eco-UHPC containing 50 wt% of limestone filler. Two typ...

An efficient solution to increase the sustainability of building materials is to replace Portland cement with alkali-activated materials (AAM). Precursors for those systems are often based on water-cooled ground granulated blast furnace slags (GGBFS). Quenching of blast furnace slag can be done also by air but in that case, the final product is cry...

Exposure conditions are critical for the autogenous self-healing process of Portland cement based binder matrixes. However, there is still a significant lack of fundamental knowledge related to this factor. The aim of this paper was to investigate and understand the effects of various potentially applicable curing solutions on the efficiency of the...

Waste management is emerging as one of the most troublesome and critical problems of the upcoming decades. Therefore, the utilization of industrial by-products as building materials components has been widely studied in recent years. Geopolymer concrete, with binder entirely substituted by slag or fly ash, is one of the materials, which combines po...

It is commonly accepted that the autogenous self-healing of concrete is mainly controlled by the hydration of Portland cement and its extent depends on the availability of anhydrous particles. High-performance (HPCs) and ultra-high performance concretes (UHPCs) incorporating very high amounts of cement and having a low water-to-cement ratio reach t...

Self-healing can be defined as the ability of a material to repair inner damage without any external intervention. In the case of concrete, the process can be autogenous, based on optimized mix composition, or autonomous, when using additionally incorporated capsules containing a healing agent and/or bacteria spores. The first process uses unhydrat...

The specific surface area (SSA) of constituents in a concrete mixture has a significant effect on its workability in fresh state. Excess layer theories relate the SSA to the flow behaviour of mixtures and can be used as part of an approach to mix design. However, measurement of SSA is complex and includes several issues, and thus is commonly replac...

The efficiency of the mechanochemical activation (MCA) is influenced by various process parameters as well as by the properties of the treated material. The main objective of this research was to optimize the MCA process, gaining enhancement of the chemical reactivity of a Swedish raw clay, which is going to be used as an alkali-activated cementiti...

Shale, a fine-grained sedimentary rock, is composed of highly compacted clay particles, nanometric porosity and silt-sized particles of other minerals. In this paper, a combined use of X-Ray micro-CT and nanoindentation tests is proposed for the qualitative and quantitative characterization of this material. The individual methods are utilized at d...

This paper proposes homogenization scheme for estimating the effective thermal conductivity of fully saturated soils. This approach is based on the random checkerboard-like microstructure. Two modeling scales and two modeling approaches are distinguished and used, i.e. microscale and mesoscale and 1-step and 2-step homogenizations, respectively. Th...

The aim of this work was to develop an efficient approach to prepare a macroporous scaffold for sophisticated bone replacement, avoiding a long-lasting and complex methodology. Such a scaffold based on the 3-(trimethoxysilyl)propyl methacrylate-POSS hybrid was synthesized via reaction of 3-(trimethoxysilyl)propyl methacrylate and the trifluorometha...

This paper presents the nanoindentation investigation of the evolution of concrete microstructure modified by the Internal Crystallization Technology mineral powders. The samples under study were retrieved from a fragment of a circular concrete lining of the vertical mine shaft at a depth of approximately 1,000 m. Due to the aggressive environment...

There are a significant number of factors which have impact on the scale effect in the mechanical behaviour of composite materials. In this paper, the influence of the microstructure on this phenomenon is examined. In particular, how the results of the uniaxial compression test are affected by the microstructure geometry is verified. For the purpos...

This paper deals with the use of X-ray microtomography in evaluating the porosity of barrage lock concrete. The main parts of the lock were built in the years 1914-1917. Its high and low heads were founded on 2.70 m thick concrete slabs. Samples for laboratory tests were taken by core drilling at half of the slab thickness. The compressive strength...

The aim of this paper is to present an example of the material microstructure characterization with the use of X-ray micro-CT and nanoindentation measurements. Firstly, the current scope of application of the aforementioned techniques is provided within different fields of science. Then, background of each of the methods is presented. The methodolo...

In order to properly design a shaft it is necessary to acquire full information about the rock mass in the exploration area. It is especially crucial in the case of the deposit of an unusual vertical intrusion shape, occurring at a great depth. Such a situation implies that the shaft lining design must take into consideration not only the geomechan...

The paper presents the results of the laboratory investigation of thermal conductivity of clayey soils subjected to different moisture contents. The conductivities of soil specimens are evaluated at two extreme cases: fully saturated and dried state. The latter state is achieved by drying the soil specimens in the temperature 105 °C. The needle pro...

The aim of the study is to identify the scale effect in composites with morphology of “matrix-inclusion” type. The time scale effect due to the microstructure is investigated by considering the standardized needle probe test, which is recently used for evaluation of thermal conductivity of solid materials. The microstructure of the material investi...

The needle probe test, as a thermal conductivity measurement method, has become very popular in recent years. In the present study, the efficiency of this methodology, for the case of composite materials, is investigated based on the numerical simulations. The material under study is a two-phase composite with periodic microstructure of “matrix-inc...

The article presents an application of X-ray microtomography for identification of the carbonation zone in concrete material. A concrete specimen subjected earlier to harsh environmental conditions is investigated. The material is firstly checked with the use of chemical corrosion indicators and then is subjected to microstructural analysis perform...