Polyester Resin Concrete Research Articles

Experimental Study on the Bond Performance between Fiber-Reinforced Polymer Bar and Unsaturated Polyester Resin Concrete

Fiber-reinforced polymer (FRP) bar-reinforced unsaturated polyester resin concrete (UPC) can solve the problem of rebar corrosion in ordinary reinforced concrete members. However, it has not been widely used in engineering practice because there have been few studies conducted on the bond behaviors of FRP bar and UPC, and the interaction mechanisms between FRP bar and UPC have not been well understood. A series of pull-out tests are conducted on FRP bar-UPC specimens to study the bond behaviors between these two materials. Parametric studies are also carried out to investigate the effects of FRP bar diameter, fiber type, type of surface treatment, concrete cover thickness, and interfacial bond length between the two. Three failure modes of the specimens are observed from pull-out tests, i.e., FRP bar pull-out, tensile failure of FRP bar, and UPC split. A new constitutive model is, therefore, proposed to predict the bond stress of FRP bar and UPC in the residual stage, and the proposed model is finally verified by test data reported in this study.

Strength Reduction Mechanism and Strength Estimation of Unsaturated Polyester Resin Concrete Deteriorated in Outdoor Soil

Strength Reduction Mechanism and Strength Estimation of Unsaturated Polyester Resin Concrete Deteriorated in Outdoor Soil

Effect of Hydrocarbon Solutions on Polymer Concrete

The damaging effect of oil products on concrete besides the high permeability of concretehave made researchers try to improve the properties of concrete exposed to oil products, hence improving the durability and serviceability of oil concrete structures. Polymer concrete exposed to oil products is one of a new field that deals with the enhancement of concrete durability. In the present work polyester resin concrete was used and then immersed in different types of oil exposure liquids (gasoline, gas oil and kerosene) compared with reference concrete which left in the air. Polyester resin concrete is used as a new type in this field, it is noteworthy that the use of this concrete gives good test results that raise the values of the mechanical properties, so we did the SEM test in an attempt to study the microstructure of this concrete after soaking for 90 days in oil products.

RETROFITTING ON FLEXURAL STRENGTH OF RC COLUMNS USING POLYESTER RESIN CONCRETE

Concrete column structures damages due to flexural moment need to be repaired and strengthened to avoid of sudden failure by applying appropriate methods. The method applied in this study was retrofitting by applying polyester resin concrete. In order to know the effect of polyester resin concrete against axial load capacity, stiffness, ductility and the damage pattern of columns by eccentrically loaded, an experimental laboratory was carried out. In this study, three column specimens are tested. The dimension of the specimen is 150 mm x 150 mm and the high of the column are 1200 mm with the effective high is 600 mm and 600 mm for corbel. The column specimens have a fixed eccentricity of 50 mm. First, initial column tested before yield point of reinforcing bar reached and concrete crack limited to 0,4mm. Further, retrofitting applied to each initial column specimen using normal concrete and polyester resin concrete with the level of resin 15% and 20%, respectively. Retrofitting column tested again with the same loading of initial column until it reaches the collapse load. The result of experiment compares to analysis method by Nawy and Whitney which represent the analysis of normal concrete column capacity. The result showed that levels of resin to be used is 20% because of better workability compared to 15% resin. Further, compressive test on resin concrete cylinder showed that the resin level at 15% and 20% are 82.82 MPa and 76.65 MPa, respectively. The strength of KR-ii decreased about 33.523%. The strength of KR-15ii and KR-20ii increased 5.08% and 24.827% respectively compared to initial column. Specimen column stiffness KR-ii. KR-15ii and KR-20ii decreased about 76.22%, 24.50% and 37.65%, respectively from the initial column. Furthermore, ductility of KR-ii, KR-15ii and KR-20ii decreased about 1.512, 1.250 and 2.50, respectively. The changes of the ultimate capacity load of KR-ii, KR-15ii and KR-20ii by Nawy Method respectively -26.54%, 12.66%, and 13.83%, whereas the method of Whitney respectively -17.68%, 26.25%, and 27.56%. The use of polyester resin concrete can change the pattern of collapse from brittle to ductile columns.Keywords: retrofit, ductility, stiffness, flexural column, eccentricity

Durability of Polyester Resin Concrete in Different Chemical Solutions

Polymer concretes (PC) were introduced to building and construction industry more than 50 years ago. Gradually, they became a suitable substitute for concrete structures; however, their application was shortly diminished due to the higher costs. In this research a homemade cost-quality effective resin (unsaturated polyester) is used as binder in the polymer concrete production. Laboratory specimens made and evaluated for compressive stregth tests. A comparative study was performed on effect of different chemicals (organic and inorganic acids, alkalis, sodium sulfate, gasoline and water) on durability of the polymer concrete specimens after six months of exposure.

Influence of moisture content on the thermal and mechanical properties and curing behavior of polymeric matrix and polymer concrete composite

The effect of moisture on the thermal and mechanical properties and curing process of unsaturated polyester resin and polymer concrete was investigated. The resin curing kinetics were studied using DSC and the results were analyzed using Borchardt and Daniels’ model. The results showed an increase of reaction order and activation energy, and a decrease in the heat of reaction with increasing initial moisture content. The 70% conversion time increased from 17.5 to 64min when initial moisture content increased from 0% to 5%. The mechanical properties of both unsaturated polyester resin and polymer concrete deteriorated dramatically with increasing moisture content. The resin Shor D hardness decreased from 85 to 67MPa, the flexural strength from 144 to 30MPa, the modulus of elasticity from 2.99 to 1.05GPa, and the tensile strength from 58.6 to 30MPa when initial moisture content increased from 0% to 5%. The polymer concrete’s flexural strength decreased from 25.8 to 0.68MPa and compressive strength from 190 to 85MPa when the initial moisture added to the aggregate content increased from 0% to 5%. The coefficient of thermal expansion of the resin increased from 80×10−6 to 123×10−6°C−1 and of the polymer concrete from 13×10−6 to 19.8×10−6°C−1 when the initial moisture content increased from 0% to 5%.

Optimization of Compression Strength by Granulometry and Change of Binder Rates in Epoxy and Polyester Resin Concrete

Polymer concretes are composite materials comprised of two or more different materials. The fillers are compounds such as resin, hardener, accelerator, colorant, or matrix structure reinforcing materials. When it is considered as a building component for the body of a machine tool, machine or application, different compounds are prepared for the target application. By means of an appropriate design, production and tests that can resist the working conditions, it is possible for any composite to obtain the desired result. For this purpose, it is necessary to determine many mechanical properties. The pressure strength is therefore a basic feature to know. Within the framework of this study, the change in pressure strength was elaborated on the basis of the different aggregate distribution and binder rates designed on the standard cement granulometric curves. The used binders and fillers were polyester and epoxy resin and quartz respectively. The results comply with the literature, and it was found that an appropriate mixture optimization is possible for the desired strength.

Thermal properties of polymer concrete using glycerol methacrylate/styrene system at low temperature

This paper describes the results of thermal fracture test and flexural test of polymer concrete using glycerol methacrylate/styrene system (GM/St) as binder. This concrete can harden at low temperatures. The test also includes polymer concrete using unsaturated polyester resin(UP) and cement concrete. The thermal fracture test was carried out at a constant rate of cooling in order to record stress-temperature curves. It was concluded that the thermal stresses of GM/St mixtures cured at a low temperature were smaller than those in the same mixtures and UP mixtures cured at a normal temperature. Those polymer concretes could resist the thermal stress at low temperatures until -40°C and did not fracture. The flexural strengths of those are found constant regardless of temperatures. On the other hand, cement concrete was fractured by a smaller thermal change from the initial temperature than that of polymer mixtures.

コンクリートの曲げ強度の推定に関する破壊力学的検討

Size effects and shape effects on the flexural strength of concrete were examined through experiments and numerical analysis with fracture mechanics concepts. Based on the numerical results, the authors proposed an equation for estimating the flexural strength of concrete beams with square or circular cross sections. The beam depth, tensile strength, and the characteristic length of concrete beams are the parameters in the proposed equation. The estimated values of flexural strength given by the equation are in good agreement with the experimental results, especially for square beams. The equation gives moderate values for the flexural strengths of various kinds of concrete, including normal concrete, high-strength concrete, lightweight concrete, mortar, and polyester resin concrete.

Efficiency of some silane coupling agents and of the method of their application in polyester resin concrete

The effects of two silane coupling agents, γ-methacryloxy propyl trimethoxy silane and γ-amino propyl triethoxy silane, on the compressive strength of polyester resin concrete (PC) is studied by using two methods of application of the coupling agent, namely by (a) pre-treatment of the aggregates in an aqueous solution of the silane, (b) by adding the silane to the resin as an integral blend additive. The performance of the two methods, evaluated in terms of gain in the compressive strength, is compared. Method (b), which is preferable due to its convenience, showed comparable performance to method (a) only at the optimum level of loading of the coupling agent. Changes in X-ray diffraction of “PC with coupling agent” prepared by method (b) were similar to those in silane-treated sand particles, which support the migration theory of the coupling agent reported in the literature. Grain size analysis of silane-treated sand showed evidence of better aggregation in the presence of one coupling agent as compared to the other.

Role of styrene-based shrinkage reducing agent in polyester resin concrete

Studies on the reduction of setting shrinkage of polyester resin concrete with and without the microfiller CaCO 3 by using a styrene/polysterene shrinkage reducing agent are reported. The setting shrinkage of unmodified polyester resin concrete was quite considerable but could be reduced almost to zero by varying the shrinkage reducing agent content. At high shrinkage reducing agent content, expansion of the sample was observed instead of shrinkage. Some differences in the rate of shrinkage in the initial stages of curing were observed, which provides some insight into the role of the two components of the shrinkage reducing agent in the reduction of shrinkage. Reduction of shrinkage was accompanied by a reduction in compressive strength, which suggests the need for a proper compromise between these two properties for developing polyester resin concretes for specific applications.

Relation between curing conditions and compressive strength of polyester resin concrete

This paper deals with the strength development of polyester resin concrete under various curing conditions. The polyester resin concrete was mixed with standard mix proportions containing binders with various working lives, and the resin concrete specimens were prepared under various curing conditions. The cured specimens were then tested for compressive strength. The test results indicated the following: 1. 1. The optimum precuring period before heat curing for the resin concrete is about 10 hours. 2. 2. It is suggested that water cure is applicable to the resin concrete without noticeably harmful hydrolysis of polyester resin used. 3. 3. The compressive strength of the heat cured resin concrete is considerably high as compared with that of water and dry cured concretes.

Some structural studies on polyester resin-concrete containing silane coupling agents

Some structural studies on polyester resin-concrete containing silane coupling agents

ポリエステルレジンコンクリートの強度に及ぼす影響

Generally, the steam curing method is adopted as an accelerated curing method of cement concrete products, but very few reports concerning the properties of steam-cured polyester resin concrete have appeared until now, in fear of hydrolysis of polyester resin by hot water or steam. In precast polyester resin concrete factories, the relatively expensive heat cure method by circulation of hot air is usually adopted for curing of products. The objective of this study is to examine the possibility of applying steam cure to polyester resin concrete in the same manner as cement concrete.Polyester resin concrete (polymer concrete) is mixed with variable catalyst or accelerator content for liquid resin in selected mix proportion, and the resin concrete specimens are prepared under various steam-curing conditions. The cured resin concrete specimens are tested for tensile and compressive strengths. The test results indicate that, in the catalytic system for ordinary temperature cure, the strength development of polyester resin concrete is accelerated by steam cure without noticeably harmful hydrolysis of polyester resin observed.

MIX PROPORTIONS AND PROPERTIES OF POLYESTER RESIN CONCRETE

Polyester resin concrete is a type of concrete that is prepared by binding aggregate with polyester resin (as a binder) without inorganic cements. The mix proportions of polyester resin concrete have not been studied systematically until now. This paper contains a summary of the method used to obtain the most satisfactory mix proportion of polyester resin concrete and a discussion on the properties of this concrete. /ACI/