Use of Polymer Concretes

The main limitation of the wide application of PCs is their relatively high material cost. This is why it is important to find the optimum technical-economic compromise [8], 

Due to its properties, polymer concrete is currently used in many applications  

The most effective scopes of polymer concrete application, depending on the type of polymeric binder, are shown in Table 1.6. 

In conclusion, it should be emphasized that the main advantage of polymer concretes is high chemical resistance characterized by long-term resistance to corrosive environments. Composition based on polymer binders are the most promising for use in these conditions. 

Good adhesive properties Low shrinkage Superior chemical resistance 

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FIGURE 1.1 Composition of a polymer concrete. Intended Use of Polymer Concrete, Systemy i Technologie, http //www.sytec.p1/en/polimerobeton-en.php wlasciwosci-bet onow-zywicznych. 

Dinitz, A. M., The Use of Polymer Concrete Materials for Construction, Maintenance, Rehabilitation, and Preservation of Concrete and Steel Orthotropic Bridge Decks, http //media.brintex.com/Occurrence/21/Brochure/678/brochure.pdf. 

Where it is considered essential to apply a granolithic topping onto an existing concrete substrate the danger of de-bonding can be much reduced by the use of polymer-based bonding aid. Two types of bonding aid are commonly used ... 

Comparing the cost of the various concretes shows that at times of low sulfur prices, sulfur concrete can even compete with high-strength cement concrete. The costs of polymer concrete per cubic meter are quite enormous. Yet the substantially higher production costs of polymer concrete have not been considered yet. The prices used for this comparison are based on European conditions. To assess the sulfur concrete costs we used two extreme sulfur prices which had to be paid,in the last years. The total costs of DCP-modified sulfur concrete rose only negligibly with the addition of this plasticizer (Table IX). 

A final possibility. Design once again as in the first instance with a uniform, constant depth, place the membrane and lay the walls, then use a polymer concrete castable to establish the slope. If the trench is a long one, the concrete bottom can be stepped at each point where the depth increases by exactly one brick depth. Now, after applying the membrane, the slopes can be established with a polymer concrete without having to worry too much at the material cost of a larger volume of polymer concrete. 

Polymer concretes show excellent mechanical properties and chemical resistance compared with conventional cement concretes. Polymer concretes can be cured quickly by the use of curing agents. Thus, the applications of polymer concretes are being increased. One of the popular polymers for polymer concretes is unsaturated polyester (UPE) resin. The properties of UPE resin can be modified by changing its molecular features. For the synthesis of the resin, phthalic anhydride or isophthalic acid as well as maleic anhydride can be employed to modify the mechanical properties or hydrothermal resistance. Terephthalic acid which is also used for the synthesis of poly ethylene terephthalate (PET) enhances the thermal resistance of the cured UPE resin. However, the synthesis of unsaturated polyester resin from terephthalic acid is difficult. One method to synthesize unsaturated polyester from terephthalic acid is the use of recycled PET. 

The high cost of resins used in the production of polymer concrete (PC) makes the material expensive relative to cement-based materials. Not surprisingly, a recent survey ranked lower cost resins as the most important future need for PC [1], Recently, some work has been done on the production of unsaturated polyester resins based on recycled poly (ethylene terephthalate), PET [2], The PET wastes are typically found in used beverage bottles, and many states have passed legislation to collect and recycle these bottles. If specially formulated, the unsaturated polyester could be used in the production of PC [3],... 

Rebeiz, K., Fowler, D.W., Paul, D. (1991) An Overview on the Properties of Polymer Concrete Using Recycled Plastics, University of Texas at Austin. 

Polymer concrete, as highly filled polymer compositions, can be prepared on any synthetic binding. However, due to the requirements for density, strength, deform-ability, chemical resistance, and other characteristics, about 10 different types of monomers or oligomers are used in practice. In combination with modifying additives, they provide more than 30 varieties of polymer concrete. 

All this testifies to the fact that the maximum effect is obtained with the use of polymer coating for strengthening of reinforced concrete beams and simultaneously for further corrosion protection. 

It is well known that polymer concrete (PC) is used in severe conditions in industrial and public buildings, as well as in transportation and hydraulic structures. The main advantages of polymer concrete over ordinary concrete are improved mechanical strength, low permeability, and improved chemical resistance. The main limitation is their relatively high material cost. For this reason, it is important to find the optimum technical-economic compromise. 

Recent developments in this field seem to suggest that both epoxy or polyester resins are often times used for similar applications with no apparent difference in the performance of the materials. Ohama and co-workers (15) compared the resistance of polymer concretes to boiling water for periods of up to 12 months and found that epoxy resins were more resistant than orthopthalate based... 

American Concrete Institute (ACI) ACI 548.IR-92 Guide for the Use of Polymers in Concrete (1992) ACI 548.4 Standard Specification for Latex-Modified Concrete (LMC) Overiays(1992) ACI 546.1 R Guide for Repair of Concrete Bridge Superstructures (1980) ACI 503.5R Guide for the Selection of Polymer Adhesives with Concrete (1992)... 

The mechanical properties, the corrosion stability, and some useful properties are the reasons for the continuous interest shown in polymer-concrete composites by various design, research, and production organizations. The most important types of polymer-concrete composites are polymer-impregnated concrete (PIC), polymer-cement concrete (PCC), and polymer concrete (PC). 

PIC is a precast and cured portland cement concrete that has been impregnated with a monomer that is subsequently polymerized in situ. This type of cement composite is the most developed of polymer-concrete products. PCC, on the other hand, is a modified concrete in which a part (10%-15% by weight) of the cement binder is replaced by a synthetic organic polymer. It is produced by incorporating a monomer, prepolymer-monomer mixture, or a dispersed polymer (latex) into a cement-concrete mix. To effect the polymerization of the monomer or prepolymer-monomer, a catalyst (initiator) is added to the mixture. The process technology used is very similar to that of conventional concrete. So, unlike PIC which has to be used as a precast structure, PCC can be cast-in-place in field applications. PC can be described as a composite that contains polymer as a binder instead of the conventional portland cement. 

Hence, the considered above scheme of genetic intercommunication of synthesis products and condensed state structures with polymer properties demonstrates clearly, that the foundation of the latter lays (encodes) quite at the synthesis stage and cannot be set by only singular polymer macromolecule chemical structure. The using of the concrete quantitative model of solid polymers structure together with fractal analysis methods gives the possibility of prediction of not only glass transition temperature T, but also polymers other important properties munber [120]. 

Development of strengthening (or retrofitting) methods by the troweling or shotcreting work of polymer-modified mortar and of exfoliation (or delamination) prevention methods by use of polymer-modified paste or mortar with fiber sheets for reinforced concrete structures [69-71]... 

ACI Committee 548 ACI 548, IR-09 Guide for the Use of Polymers in Concrete, American Concrete Institute, Farmington Hills, Michigan (2009). 

The use of polymers must be accompanied by the adoption of a greater mix of energy, so that its effects are more intense and evenly distributed in the cement matrix. The analyze of concrete microstructure is a good way to assess the behavior of mechanical properties and others properties, by the visualization of formed hydrates of Portland cement and its distribution. Research into the combination of polymers with different characteristics appears to be a noteworthy path to continue. 

Fig. 5 shows the air content of the concrete in relation to polymer dosage. The use of polymers other than PVA-P did not significantly affect the air content regardless of dosage. However, the air content of the mixture with PVA-P increased remarkably with increased dosage. 

Repair of concrete and cement-polymer composites using of polymer flexible joints... 

Figure 11. Three-point bending test on concrete specimens (500x100x100 mm). Tested specimen just after failure and after repair using of polymer flexible joint...

Effectiveness of repair using of polymer flexible joint tested on airfield concrete pavements... 

Observations demonstrated that bonding of concrete slabs with polymer PM reduces vertical and horizontal deformations of them of about 50%, allowing for safe work of airfield pavements. It should be noticed that contractions joints deform horizontally of about 5 mm between winter and summer and similar value was measured in cases of vertical deformation. An example of 24 hours measurements of vertical displacements of airfield slab is presented in Fig. 16 (for original slab with bituminous filling and slab bonded with polymer PM). Comparison of vertical displacement shows that the use of polymer joints in contradiction to bituminous mass reduces warping deformations of the comers about two times, what is very advantageous in aspect of airfield exploitation. 

A. Kwiecieh New repair method of cracked concrete airfield surfaces using of polymer joints. 13th Int. Congress on Polymers in Concrete ICPIC 2010, pp. 657 - 664. 

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