INTENSIFICATION OF GEOCRETE BEAM WITH GFRP USING ABAQUS

Abstract

Concrete is a versatile material having number of desirable properties, so widely preferred in construction industry. But having major disadvantage that under severe vibrations such as earthquakes it gets cracked and concrete has poor modification and repair quality. Therefore some repair or strengthening must be performed so that damaged element must stand for further useful life. Many civil structures are no longer considered safe due to increased load specifications in the design codes. Such structures must be strengthened in order to maintain their serviceability[4]. As the demand for concrete as construction material increases, the demand for Portland cement also increases. It is estimated that the production of cement will increase from about 1.5 billion tons in 1995 to 2.5 billion tons in 2015. On the other hand, the climate change due to global warming is caused by the emission of greenhouse gases, such as carbon dioxide (CO2), into the atmosphere by human activities. Among the greenhouse gases, CO2 contributes about 65% of global warming. The cement industry is held responsible for some of the CO2 emissions, because the production of one ton Portland cement emits approximately one ton of CO2 into the atmosphere. Several efforts are in progress to reduce the use of Portland cement in order to address the global warming issues. These include the utilization of supplementary cementing materials such as fly ash, silica fume, granulated blast furnace slag, rice-husk ash and metakaolin, and the development of alternative binders to Portland cement. In this respect, the geopolymer technology proposed by Davidovits shows considerable promise for application in concrete industry as an alternative binder to the Portland cement. In terms of global warming, the geopolymer technology could significantly reduce the CO2 emission to the atmosphere caused by the cement industries [13]. In 1978, Professor Joseph Davidovits introduced the development of mineral binders with an amorphous structure, named geopolymers. Davidovits (1988; 1994) proposed that an alkaline liquid could be used to react with the silicon (Si) and the aluminium (Al) in a source material of geological origin or in by-product materials such as fly ash and rice husk ash to produce binders. Because the chemical reaction that takes place in this case is a polymerization process, he coined the term ‘Geopolymer’ to represent these binders. This was a class of solid materials, producedby the reaction of an alumino silicate powder and an alkaline liquid. The initial goal for the research done on these geopolymers was to find a more fire resistant binder material due to the high amount of fires in Europe at that time. This research led to the material being used as coatings for the fire protection of cruise ships and thermal protect results in a low flexural strength. Brittleness of both concrete types is compensated by conventional steel reinforcement [18].