Polymer concrete overlays

ACI (1993) Guide for polymer concrete overlays. ACI Material Journal, 90(5), 499-522. Brieton, P.R. (1994) Sealant materials properties and performance - an overview, in European Adhesive and Sealant Year Book 1994, FMJ International, Redhill, Surrey, pp. 7-8. 

ACI Committee 548 (1993) Guide for Polymer Concrete Overlays, ACI Materials Journal (Sept.-Oct.), 504. 

Pull-out tests were also conducted to measure the bond strength between the polymer concrete overlay and the Portland cement concrete substrate before and after the thermal compatibility test. The results are shown in Table 9. 

Depuy, G. Polymer Concrete Overlays for the Repair and Protection of Concrete, ICPIC 2001. The Tenth International Congress in Polymeric Concrete, Honolulu, HI, 2001. 

Overlays polymer concrete overlays are used to get a durable, almost impervious and wear-resistant surfaces on Portland cement concretes. Suitable surface texture may be obtained for appropriate skid resistance and hydroplaning characteristics. The surfaces on which overlay will be applied must be prepared to ensure good adhesion. The surface must be strong, sound, dry and clean. The monomer and aggregate systems used for polymer concrete overlays are similar to those of polymer concrete repairing materials. 

There are four different methods of applying polymer concrete overlays ... 

In premixed polymer concrete overlays, the aggregate and the monomer or resin system are mixed together in a concrete mixer and then spread over the surface and compacted. Sometimes, additional aggregate may be applied on the surface to increase skid resistance. Most of the time, a primer coat of initiated and promoted resin is applied on the concrete surface on which the overlay is to be placed. 

Polymer concrete overlays consisting of aggregate in a polymer binder have been placed experimentally. 

A bond coat of neat polymer is usually applied ahead of the polymer concrete. Blistering, which is a common phenomenon in membranes, has also caused problems in the application of polymer concrete overlays. ... 

R.Letsch (1987). Polymer Mortar Overlays—Measurement of Stresses. Proceedings of the Fifth International Congress on Polymers in Concrete, Brighton, England, pp. 119-123. 

Sprinkel, M. M., Twenty-Year Performance of Latex-Modified Concrete Overlays, Polymer-Modified Hydraulic-Cement Mixtures, STP-1176,pp. 141-154, American Society for Testing and Materials, Philadelphia (1993)... 

Rehabilitation is achieved by overlays such as latex-modified concrete, low-slump concrete, high-density concrete, and polymer concrete. They are commonly used for the rehabihtation of bridge decks. This procedure extends the life of a bridge deck by about 15 years. Impressed-current CP systems on bridge decks are now a routine rehabihtation teehnique because of the cooperative research with industry and states in the development of durable anodes, monitoring devices, and installation techniques. Titanium mesh anode, used in conjunction with a concrete overlay to distribute protective current, serves as a durable anode for use in impressed-current CP of reinforced concrete bridge deeks and widely accepted by state and other transportation agencies. 

Surface Barriers The application of an overlay of low-slump concrete, latex-modified concrete (EMC), high-density concrete, polymer concrete, or bituminous concrete with membrane on the existing concrete provides a barrier that impedes continued intrusion of chloride anions, moisture, and oxygen that are necessary for continued corrosion. These barrier systems may be used only after decontamination because corrosive agents get trapped in the concrete, leading to loss in its capacity to function properly. 

Conductive polymer mound anode system used platinized-niobium copper wire anode with the conductive polymer mounded on wire anode and rigid concrete overlay on top. Estimated cost is 137/m with a service life of 20 years. 

M. M. Sprinkel Twenty-five-year experience with polymer concrete bridge deck overlays, in ... 

Unless a portion of the original concrete is removed and replaced with a higher strength material, then a concrete overlay will usually result in an increase in member self weight. Applications at ground level are therefore more common than in suspended beams or slabs, although the use of polymer modified concrete overlays has found some favour in the refurbishment of bridge decks in North America(9). 

Applications of polymer mortars and polymer concretes include patching of Portland cement concrete, floor and pavement overlays, anti-corrosive linings, precast products, vaults, panels [8,11]. These indicate that there is no single polymer concrete that performs all of these tasks. Application and performance of polymer concrete depend on the binder used and the aggregate. Copolymerisation techniques allow the production of a wide range of binders with varying properties [11]. 

Latex-modified concrete is conventional Portland cement concrete with the addition of a polymeric latex emulsion. The water of suspension in the emulsion hydrates the cement and the polymer provides supplementary binding properties to produce a concrete with a low water-cement ratio, good durability, good bonding characteristics and a high degree of resistance to penetration by chloride ions, all of which are desirable properties in a concrete overlay. 

Latex-modified mortars and concretes have become promising materials for preventing chloride-induced corrosion and for repairing damaged reinforced concrete structures. In Japan and the USA, latex-modified mortar is widely used as a construction material in bridge deck overlays and patching compounds, and for finishing and repairs [99]. Polymer-cement hydrate-... 

Redispersible polymer powders are widely used to produce prepackaged-type products such as decorative wall coatings, ceramic tile adhesives, self-leveling floor overlays, and patching mortars for concrete structures. 

K. Satoh and K. Komada Study on peeling behavior of bond interface of concrete members retrofitted by surface overlaying with polymer cement mortar (in Japanese). JSCE Journal of Materials, Concrete Structures and Pavements Vol.59, No.732 (2003), pp.77-87. 

After milling, and deeper removal where cracking and spalling has occurred, the deck is then patched in the delaminated areas and a dense cementitious overlay of microsilica, polymer modified or low slump, low water/cement ratio concrete is put back on. This will slow the corrosion rate and the appearance of further delaminations. 

Overlays may be of polymer modified concretes, low slump dense concrete (the Iowa mixes), or microsilica concretes. They vary in cost and ease of application. State highway agencies generally develop one or two mix designs that suit their purposes and make competitive bidding possible. 

Figure 11.9. SM-100 styrene-butadiene copolymer latex-modified mortar overlay on concrete substrate fractured at 90° to the overlay-concrete interface. A microcrack between a sand grain in the concrete substrate (lower left) and the latex-modified mortar (upper right) is spanned by microfibers of polymer. (Isenburg and Vanderhoff, 1973.)... 

The dispersed polymer phase throughout the concrete causes considerable reduction in porosity and microcracks in the Portland cement matrix as well as serving as an additional binding material [11, 19]. Thus, PPCC is a more durable and weather resistant material for deck coverings and parking lot overlays. 

ICRI Guideline No. 310.2, Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Overlays. International Concrete Repair Institute (ICRI). 

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