To prevent expanded polystyrene(EPS) beads from rising up to the surface in the molding process of EPS lightweight concrete,vibration with pressure was applied and the polyvinyl acetate(PVA) emulsion was adopted to im...To prevent expanded polystyrene(EPS) beads from rising up to the surface in the molding process of EPS lightweight concrete,vibration with pressure was applied and the polyvinyl acetate(PVA) emulsion was adopted to improve its mechanical properties.The mechanical properties,thermal properties and durability of EPS lightweight concrete were tested.The microstructures of EPS lightweight concrete were observed by scanning electron microscope(SEM).Vibration with pressure reduces the number of small cracks.The 180 d compressive strength and flexural strength increase obviously as a large amount of PVA was added.The mixed amount of PVA has no obvious influence on the thermal performance when it is not more than 10% of the cement.Vibration with pressure and surface modification of EPS beads by PVA improve the combination of EPS beads with cement stone and the mechanical properties of EPS lightweight concrete.展开更多
As the construction of high-rise building becomes popular,improvement and innovation are required to expand the product line of lightweight concrete.In this paper,two ways of fabricating lightweight concrete were comb...As the construction of high-rise building becomes popular,improvement and innovation are required to expand the product line of lightweight concrete.In this paper,two ways of fabricating lightweight concrete were combined to make a new kind of super lightweight concrete.Normal aggregate is replaced with expanded polystyrene(EPS) granule,while foam is introduced to facilitate fabrication process.As a result,super lightweight concrete denoted as EPS foamed concrete is fabricated,whose bulk density is less than 500kg/m^3.Compressive properties of EPS foamed concrete with bulk density 300—500 kg/m^3 were investigated by stress-strain curve. It’s demonstrated that the compressive strength ranges from 0.7 to 2.5 MPa,which is higher than that of similar products.Furthermore,low elastic module and high residual to ultimate strength ratio ensure its excellent deformation and energy absorption capacity.At last,numerical analysis was performed to interpret the inherent variation of elastic modulus and failure mechanism of this material.The results show that EPS foamed concrete is a kind of super lightweight,easy to fabricate material with excellent compressive property and profound utilization potential.展开更多
基金Supported by Tianjin Natural Science Foundation (No.06YFJMJC05900)Science and Technology Key Project of Hebei Province (No.05213810)
文摘To prevent expanded polystyrene(EPS) beads from rising up to the surface in the molding process of EPS lightweight concrete,vibration with pressure was applied and the polyvinyl acetate(PVA) emulsion was adopted to improve its mechanical properties.The mechanical properties,thermal properties and durability of EPS lightweight concrete were tested.The microstructures of EPS lightweight concrete were observed by scanning electron microscope(SEM).Vibration with pressure reduces the number of small cracks.The 180 d compressive strength and flexural strength increase obviously as a large amount of PVA was added.The mixed amount of PVA has no obvious influence on the thermal performance when it is not more than 10% of the cement.Vibration with pressure and surface modification of EPS beads by PVA improve the combination of EPS beads with cement stone and the mechanical properties of EPS lightweight concrete.
基金the National Natural Science Foundation of China(No.50708059)the Open Fund of Key Laboratory of Advanced Civil Engineering Materials (Tongji University),Ministry of Education (No.K201002)
文摘As the construction of high-rise building becomes popular,improvement and innovation are required to expand the product line of lightweight concrete.In this paper,two ways of fabricating lightweight concrete were combined to make a new kind of super lightweight concrete.Normal aggregate is replaced with expanded polystyrene(EPS) granule,while foam is introduced to facilitate fabrication process.As a result,super lightweight concrete denoted as EPS foamed concrete is fabricated,whose bulk density is less than 500kg/m^3.Compressive properties of EPS foamed concrete with bulk density 300—500 kg/m^3 were investigated by stress-strain curve. It’s demonstrated that the compressive strength ranges from 0.7 to 2.5 MPa,which is higher than that of similar products.Furthermore,low elastic module and high residual to ultimate strength ratio ensure its excellent deformation and energy absorption capacity.At last,numerical analysis was performed to interpret the inherent variation of elastic modulus and failure mechanism of this material.The results show that EPS foamed concrete is a kind of super lightweight,easy to fabricate material with excellent compressive property and profound utilization potential.
