The aim of this study is to determine the radon and natural radioactivity concentra-tions of some building materials and to assess the radiation hazard associated with those mortar materials when they are used in the ...The aim of this study is to determine the radon and natural radioactivity concentra-tions of some building materials and to assess the radiation hazard associated with those mortar materials when they are used in the construction of dwellings.Radon measurements were realized by using LR-115 Type 2 solid state nuclear track detec-tors.Radon activity concentrations of these materials were found to vary between 130.00±11.40 and 1604.06±40.5 Bq m^(-3).The natural radioactivity in selected mortar materials was analyzed by using scintillation gamma spectroscopy.The activity concentrations for 226Ra,232Th and 40K for the studied mortar materials ranged from ND to 48.5±7.0 Bq kg^(-1),ND to 41.0±6.4 Bq kg^(-1)and ND to 720.4±26.8 Bq kg^(-1),respectively.Radium equivalent activities,external and internal hazard indexes,gamma and alpha indexes and absorbed gamma dose rates were calculated to assess the radiation hazard of the natural radioactivity in studied samples.The calculated Raeq values of all samples were found to be lower than the limit of 370 Bq kg-1 set for building materials.The estimated hazard index values were found to be under the unity and the absorbed dose rate values were also below the worldwide average of 84 nGy h^(-1).展开更多
Cement is the most consumed building material in the world.However,cement manufacture is responsible for 5-7%of the world CO_(2)emissions.In this paper,cement was partially replaced by styrene-butadiene rubber(SBR)pol...Cement is the most consumed building material in the world.However,cement manufacture is responsible for 5-7%of the world CO_(2)emissions.In this paper,cement was partially replaced by styrene-butadiene rubber(SBR)polymeric latex in order to reduce cement consumption.Besides,effects of SBR addition on the strength and physical properties of plain mortar exposed to three different curing regimes are presented.Three different curing regimes were applied to the 40×40×160 mm prismatic mortar specimens:(Ⅰ):Specimens were cured in water until the test age(CW),(Ⅱ):after demoulding,specimens were immersed in water for 2 days and kept in ambient temperature until the time of the test(2DWA)and(Ⅲ)involved 2 days of water curing followed by 1 day in an oven at 50℃and subsequentely placing in ambient temperature until the test time(2W1OA).Results showed that combin-ing 2 days of water curing followed by ambient temperature curing(2DWA)along with 3%SBR polymer content showed good performance in terms of compressive strength,water absorption and void content.Moreover,a good performance in terms of flexural strength was observed by combining 2W1OA curing regime with 2%SBR content.However,the detrimental effect of water curing regime(CW)in terms of compressive and flexural strength was also observed with the increase of SBR ratio.展开更多
基金funded by the Scientific and Technological Research Council of Turkey(Project number:214M039).
文摘The aim of this study is to determine the radon and natural radioactivity concentra-tions of some building materials and to assess the radiation hazard associated with those mortar materials when they are used in the construction of dwellings.Radon measurements were realized by using LR-115 Type 2 solid state nuclear track detec-tors.Radon activity concentrations of these materials were found to vary between 130.00±11.40 and 1604.06±40.5 Bq m^(-3).The natural radioactivity in selected mortar materials was analyzed by using scintillation gamma spectroscopy.The activity concentrations for 226Ra,232Th and 40K for the studied mortar materials ranged from ND to 48.5±7.0 Bq kg^(-1),ND to 41.0±6.4 Bq kg^(-1)and ND to 720.4±26.8 Bq kg^(-1),respectively.Radium equivalent activities,external and internal hazard indexes,gamma and alpha indexes and absorbed gamma dose rates were calculated to assess the radiation hazard of the natural radioactivity in studied samples.The calculated Raeq values of all samples were found to be lower than the limit of 370 Bq kg-1 set for building materials.The estimated hazard index values were found to be under the unity and the absorbed dose rate values were also below the worldwide average of 84 nGy h^(-1).
文摘Cement is the most consumed building material in the world.However,cement manufacture is responsible for 5-7%of the world CO_(2)emissions.In this paper,cement was partially replaced by styrene-butadiene rubber(SBR)polymeric latex in order to reduce cement consumption.Besides,effects of SBR addition on the strength and physical properties of plain mortar exposed to three different curing regimes are presented.Three different curing regimes were applied to the 40×40×160 mm prismatic mortar specimens:(Ⅰ):Specimens were cured in water until the test age(CW),(Ⅱ):after demoulding,specimens were immersed in water for 2 days and kept in ambient temperature until the time of the test(2DWA)and(Ⅲ)involved 2 days of water curing followed by 1 day in an oven at 50℃and subsequentely placing in ambient temperature until the test time(2W1OA).Results showed that combin-ing 2 days of water curing followed by ambient temperature curing(2DWA)along with 3%SBR polymer content showed good performance in terms of compressive strength,water absorption and void content.Moreover,a good performance in terms of flexural strength was observed by combining 2W1OA curing regime with 2%SBR content.However,the detrimental effect of water curing regime(CW)in terms of compressive and flexural strength was also observed with the increase of SBR ratio.
