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This Syposium Publication is a compilation of 17 papers presented at the 2001 ACI Spring Convention held in Philadelphia. The flow of informative data begins with the historic beginnings through numerous creative endeavors up to today's current multitudinous uses for polymer concrete. Topics include polymer concrete overlays for the repair and protection of concrete and long-term durability of sulfur concrete in harsh chemical environments. Note: The individual papers are also available as .pdf downloads.. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP214

Deteriorating sewer facilities require rapid in-situ rehabilitation and using coating as a corrosion protection is one method currently being adopted. Hence, applicability and performance of coatings under dry and wet conditions must be investigated. Performance of a polymer concrete coating was evaluated using a combination of full scale and laboratory tests. The polyester based polymer concrete coating had a density of 1.75 g/cm3 (109 lb/ft3) and a hardness in the range of 38 to 45 (Barcol hardness). Full-scale test on coating applicability and performance on concrete substrate was performed under a hydrostatic pressure of over 103 kPa (15 psi) of water, simulating the groundwater condition. Coated concrete cylinders and clay bricks with holidays (pinholes) were used to study the chemical resistance under acidic environments to represent the worst sewer and accelerated test conditions (ASTM G 20). Bonding strength between the coating and the concrete and clay brick substrates were determined using the modified ASTM D 4541 and ASTM C 321 tests. Performance of the polymer concrete coating material was studied for over 3 years and the results are analyzed to determine the performance of the polymer concrete coating.

Strengthening and rehabilitation of reinforced concrete structures using externally bonded Fibre Reinforced Polymers (FRP) strips has become a well-established technique with a large research database. Epoxy-modified mortar (EMM) has been used in the industry for more than three decades for various strengthening and rehabilitation purposes. Epoxy modified mortar without a hardener has recently been investigated. The new EMM without a hardener includes polymerlcement ratios as low as 20 percent compared to the 40-60 percent that is usually required to provide suitable mechanical properties of conventional EMM. The new EMM utilizes the cement hydrates to polymerize the epoxy resin in the cement matrix in the absence of a hardener through ring-opening polymerization. The use of ring-opening polymerization provides EMM (without a hardener) with an interesting ability to grow through any developed crack and to repair itself, thus showing enhanced fracture toughness with age. The new self-repair epoxy mortar (SREM) has shown better mechanical performance than the conventional EMM with the same polymer/cement ratio. The objective of this work is to discuss the potential use of SREM to bond FRP laminates to existing concrete substrates in rehabilitation and strengthening applications. A multi-phase research programme examining the different strength, fracture and durability criteria of the SREM-FRP composite is proposed here. Fracture mechanics principles in conjunction with microstmctural investigations will explain and maximize the material ability to self-repair.

In recent years, sulphur concrete has proven to be capable of withstanding attack by some of the most aggressive chemicals used in industry. This fast setting, acid and salt resistant concrete is well suited for use in the mineral processing and fertilizer production industries. This paper briefly describes the properties, production, application and performance of this new construction material, with references to actual commercial installations and reviews the long term durability of these projects in harsh chemical environments.

Polymer concrete (PC) overlays are often an effective way to repair or protect concrete surfaces exposed to hostile service conditions. The various applications of PC overlays include industrial floors exposed to abrasion and chemical spillage, concrete spillways and water conveyance structures exposed to abrasion erosion and freeze-thaw attack, and bridge decks exposed to severe weather conditions, deicing salts, and heavy traffic. Three general types of PC overlays are used premixed PC, multiple-layers PC, and slurry PC. Polymer binders include methacrylate monomer systems, and epoxy, polyester, and vinyl ester resins systems. Applications of PC overlays and progress in the development of standards are discussed.