Limestone (LS) and stabilised secondary spruce chips (SCs) utilisation in wood–cement composites is still an unexplored area. Therefore, the main objective of research presented here assessment long-term behaviour cement-bonded particleboards (CBPs) modified by LS SCs. Cement (CE) was replaced 10% LS, 7% The test specimens were stored a laboratory exterior environment (Middle Europe) for up to 2 years. density, strength, modulus elasticity evaluated after 28 days, then 6-month periods....

The main goal of this study is to observe changes in microstructural properties and the mutual interaction cement pastes containing superabsorbent polymers (SAPs) fly ash. SAP a type hydrogel additive which able absorb large amounts liquid its structure. In cement-based materials, it often used early stages matrix hydration excess mixing water release later even more desirable when material exposed higher temperatures. One research goals partial substitution binder (Portland cement) by...

This paper presents newly developed polymer-cement composites.The primary binder (cement) was partially substituted byuse of blast-furnace slag and high-temperature fly ash. A lightweightaggregate – agloporite (grain size in range 1–2 mm) wasused among other components. porous aggregate is producedfrom energy by-products (fly ash). Attention focusedon the behavior composites when exposed to elevatedtemperatures (400 °C–1,000°C). The influence several differentmethods temperature decrease...

The subject of this paper is option analysis the use geopolymers as matrixes to repair mortars designated for rehabilitation reinforced concrete structures. Due their specific properties, show a high potential mainly special applications. Rehabilitation structures exposed extreme conditions field in which it possible effectively take advantage ́ exceptional properties. In particular case, we focus on comparing behaviour polymer-cement materials commonly used and one geopolymer-based mortars.

The paper informs on partial results of the research focused improvement resistance cement composites towards actuation high temperatures invoked by formation fire. Specifically it is an optimisation with use alternative raw material resources. These are primarily designed for reconstructions reinforced concrete constructions. Basic characteristics were tested specimens exposed in laboratory conditions to ambient characterized increased simulating fire real construction.

The paper deals with a comprehensive analysis of the influence applied crystallization additives on service life self-compacting concrete (SCC), specifically when exposed to effects chemically aggressive environments. Attention is focused not only additive characteristics capillary porous structure SCC, but mainly its in terms long-term concrete. individual types environments are evaluated basis set physico-mechanical and physico-chemical analyses.

Concrete exposed to high temperature considerably changes its properties down total destruction. The paper describes renovation of concrete floor damaged by a fire factory building. Individual steps determination damage structures caused temperatures are described. Structure was technically analyzed, redevelopment designed and works were carried out.

This paper presents research on the changes in properties of cement-bonded particleboard modified with particulate mixture (PM). PM replaced 4% binder (cement) and filler (spruce chips). The particleboards were tested for physical (bulk density, swelling, linear expansion due to relative humidity changes) mechanical (modulus rupture modulus elasticity). Development phase composition microstructure by XRD SEM also analysed. long-term behaviour wood-cement composites was studied over a period...

Modulus of elasticity building materials can be determined in a static way (loading press) or by means non-destructive test methods (ultrasonic pulse method and resonance method); the parameter is most frequently for concrete both determining modulus are codified Standards. Elasticity characteristics calcium silicate bricks were method. Because shape (a block with oblong foot) different from specimens (usually blocks square foot), expected frequencies verification accuracy measurement...

The problem of the presented research is stabilization spruce chips in modified cement matrix wood-cement composites and analysing effect stabilisation on selected parameters these composite materials. has an impact wood content. Silicate based Portland blended was by finely ground thermal power plant slag (TPPS) limestone (LS). Four types were subjected to water immersion tests for 28 days. During immersion, both swelling thickness mass changes analysed. amount sugars pH leachate determined...

The research presented in this paper is aimed at studying the properties of composites designed for a redevelopment reinforced concrete structures where it possible to expect an increased risk fire, i.e., shock actions extreme temperatures.Such conditions may occur, example, transport constructions, particularly tunnels.We have developed two recipes (formulas) materials based on polymer-cement matrix and porous filler.These were subjected cyclic freezing de-freezing combination with water...

This paper describes the influence of crystalline admixtures on chemical resistance cement composites exposed to aggressive environments. The effect was determined by a series physical-mechanical and innovative physical-chemical methods. Specifically, this concerned measurement flexural strength, compressive determination dynamic modulus elasticity ultrasonic pulse velocity test, an analysis internal structure mercury intrusion porosimetry x-ray computed tomography. Physical-chemical...

Dynamic Young ́s modulus of elasticity can be determined by ultrasonic pulse method and resonance method. Because the difference in way introducing tension into a test specimen, values differ. measured is higher; stated for concrete 5 to 20%. It was found that dynamic Young's calcium silicate bricks prisms on average higher 9.5% than If converted static elasticity, this has taken account means appropriate coefficient.

The paper analyses the possibility of alkali activated materials utilization as matrix for repair mortars, determined rehabilitation reinforced concrete structures, exposed to chemically aggressive surroundings. alcali have owing their specific properties a high potential especially in applications. Materials showing comparison with cement significantly higher resistance against effect chemical substances are so-called materials. structures extreme conditions is area effective extraordinary...

The article is involved in the possibility to use activated fly ashes as composite material matrices intended for extreme conditions. In particular, attention paid development of high temperature resistant materials up 1200°C. effects temperatures on developed are monitored not only by tests physical and mechanical parameters, but also using chemical analyses. focussed matrix composition optimisation selection suitable type aggregates. This complex approach allows developing with maximum...

The article analyses the possibility of using geopolymers as a matrix sprayed concretes intended for realisation constructions in environment with an increased fire risk. Thanks to their specific properties, show high resistance extreme temperatures. Thus, shows considerable potential light development resistant

When assessing a condition of reinforced concrete structures the expert companies mostly place emphasis mainly on determination material physico-chemical parameters (such as strength parameters, reinforcement placing etc.). These figures are, course, very important for example structural analysis structure, but complex assessment are these data fully insufficient. This article illustrates role when using specific example.

During their use reinforced concrete structures are exposed to external influences.Nowadays, the reducing effect of these influences is usually ensured by secondary (barrier) protection.At present, coatings based on organic substances commonly used.However, types protection show substantial limits under extreme conditions.A method that has considerable potential eliminate disadvantages includes application alkali-activated materials or geopolymers.This paper focused development and...

The paper researches lightweight mortars based on a high content of alternative materials. 25 – 30% heating plant slag was used in order to modify the matrix. Fly ash agloporite (a aggregate produced by self-combustion from fly ash) as an aggregate. Mortars were exposed temperatures up 1,250° C. Two types cooling carried out at 1,000° C; controlled slow (in furnace) and shock water baths approximate 18° C). Developed materials further analyzed various methods: monitoring changes observation...

The paper deals the possibility of alkali activated materials utilization as matrix for repair mortars, determined rehabilitation reinforced concrete structures. Alkali have owing to their specific properties a high potential especially in applications. Materials showing comparison with cement significantly higher resistance against effect chemical substances are so-called materials. One essential conditions successful use mortars is sufficient cohesion surface respectively rehabilitated

Experience obtained from often tragic road accidents has proven that in a fire the tunnel lining is destructed very intensively by high temperatures. Concrete, usually applied using sprayed concrete technology (so-called shotcreting) used for building linings of tunnels. The topic present article development mix determined so this material to maximum extent resistant extreme temperature effects occurred fire. It apparent type one way increasing safety

The paper describes manufacture, use and subsequent recycling method in several types of solar panels. possibility using secondary raw materials incurred during is also mentioned – these have not found their application so far final being dealt. Within the research conducted at BUT, way obtained from panels construction industry examined, with a focus on industrial polymer floorings.