كليدواژه :
گاما , نوترون , ضريب تضعيف خطي , حفاظت , بتن
چكيده فارسي :
در اﻳﻦ ﭘﮋوﻫﺶ ﺿﺮﻳﺐ ﺗﻀﻌﻴﻒ ﺧﻄﻲ ﭘﺮﺗﻮ ﮔﺎﻣﺎ و ﺳﻄﺢ ﻣﻘﻄﻊ ﭘﺮاﻛﻨﺪﮔﻲ ﭘﺮﺗﻮ ﻧﻮﺗﺮون دو ﺳﺮي از ﻧﻤﻮﻧﻪﻫﺎي ﺑﺘﻨﻲ ﺣﺎوي ﭘﻮدر ﺑﺎرﻳﺖ ﺑﻪ ﻋﻨﻮان ﺟﺎﻳﮕﺰﻳﻨﻲ از ﻣﺎﺳﻪ ﺑﺎ و ﺑﺪون ﭘﻮدر ﮔﺮاﻓﻴﺖ ﺗﺤﺖ اﺷﻌﻪ ﮔﺎﻣﺎ ﺑﺎ ﭼﺸﻤﻪCs-137 و آﺷﻜﺎرﺳﺎز(NaI (Tl و ﺗﺤﺖ ﭘﺮﺗﻮ ﻧﻮﺗﺮون ﺑﺎ ﭼﺸﻤﻪ-Am وBe241 و آﺷﻜﺎرﺳﺎز BF3 ﺑﺮرﺳﻲ ﺷﺪ. ﻣﻘﺎوﻣﺖ ﻓﺸﺎري، ﻣﻘﺎوﻣﺖ ﻛﺸﺸﻲ و ﺳﺮﻋﺖ ﭘﺎﻟﺲ اوﻟﺘﺮاﺳﻮﻧﻴﻚ ﻧﻴﺰ ﺗﻌﻴﻴﻦ ﺷﺪ. ﺗﻤﺎم ﻧﻤﻮﻧﻪﻫﺎي ﺑﺘﻦ، ﺑﻪ ﺟﺰ ﻧﻤﻮﻧﻪﻫﺎي ﻛﻨﺘﺮل، ﺑﺎ ﻣﻘﺪار 400 ﻛﻴﻠﻮﮔﺮم در ﻣﺘﺮ ﻣﻜﻌﺐ ﺳﻴﻤﺎن و ﻧﺴﺒﺖ آب ﺑﻪ ﺳﻴﻤﺎن0/4 ﺑﺎ ﺟﺎﻳﮕﺰﻳﻨﻲ 10 درﺻﺪ ﻣﻴﻜﺮوﺳﻴﻠﻴﺲ در دو ﺳﺮي ﺳﺎﺧﺘﻪ ﺷﺪهاﻧﺪ. در ﺳﺮي اول، ﭘﻮدر ﺑﺎرﻳﺖ ﺑﺎ ﺟﺎﻳﮕﺰﻳﻨﻲ 10، 25، 50، 75 و 100 درﺻﺪ ﺟﺎﻳﮕﺰﻳﻦ ﻣﺎﺳﻪ ﺷﺪ و در ﻣﺮﺣﻠﻪ دوم، 10 درﺻﺪ ﭘﻮدر ﮔﺮاﻓﻴﺖ ﺑﻪ ﻧﻤﻮﻧﻪﻫﺎي ﺣﺎوي ﭘﻮدرﻫﺎي ﻣﺨﺘﻠﻒ ﭘﻮدر ﺑﺎرﻳﺖ اﺿﺎﻓﻪ ﺷﺪه اﺳﺖ. ﻧﺘﻴﺠﻪ اﻳﻦ ﭘﮋوﻫﺶ ﻧﺸﺎن داد ﻛﻪ ﻳﻚ ﻧﻤﻮﻧﻪ ﺣﺎوي 10٪ ﭘﻮدرﺑﺎرﻳﺖ ﺑﻪ اﺿﺎﻓﻪ 10 ﭘﻮدر ﮔﺮاﻓﻴﺖ ﻣﻲﺗﻮاﻧﺪ ﺑﻪ ﻋﻨﻮان ﻳﻚ ﻣﻘﺪار ﻣﻄﻠﻮب ﺑﺮاي ﺑﺘﻦ ﺣﻔﺎﻇﺖ ﺷﺪه در ﺑﺮاﺑﺮ اﺷﻌﻪ ﻫﺎي ﮔﺎﻣﺎ و ﻧﻮﺗﺮون ﺑﺎﺷﺪ
چكيده لاتين :
Today in the world, including in our country, the use of nuclear technology in various fields of power plants, industry, agriculture and medicine is expanding. One of the most important issues in nuclear technology is nuclear radiation protection to prevent harmful environmental, pathogenic and harmful effects on some of the precision measuring instruments. From the perspective of preservation, all the radiation and particles are not of the same importance, because their penetration and impact on different materials, such as living tissue, are not equal. In the discussion of conservation, neutron and gamma radiation is of particular importance because, due to its unloaded nature, they can pass relatively large thicknesses of the shield and contribute to raising the dose rate outside the shield. In addition to the many uses of radioactive waste, it should be noted that this radiation damages cells and living tissues and protection against it is essential and inevitable. In order to protect against radiation, absorbent materials should have a high density, high attenuation coefficient, and structural properties with high strength, easy to provide and cheap production. According to the above, the use of concrete is a suitable alternative for radiation protection. Due to its high specificity and low cost, barite is widely used in the oil and gas drilling industry, coloring industry, pharmaceutical plastics (due to the absorption of radioactive wastes), chemicals and so on. So it can be a good option for gamma radiation protection. In this research gamma-ray linear attenuation coefficient and neutron beam dispersion cross-section of two series of concrete samples containing barite powder as a substitute of sand with and without graphite powder under gamma rays with Cs-137 fountain and NaI (Tl) detector under neutron beam With the Am-Be 241 fountain and the BF3 detector. The compressive strength, tensile strength and ultrasonic pulse velocity were also determined. All concrete samples, with the exception of control samples, have been made with 400 kg / m3 cement and 0.4 water/cement ratio with 10% microsilicon replacement in two series. In the first series, barite powder was replaced with 10, 25, 50, 75 and 100% replacement of sand, and in the second, 10% of the graphite powder was added to samples containing various powdered barite powder. The result of this study showed that a sample containing 10% barite powder plus 10% graphite powder could be an optimal amount for a concrete protected against gamma and neutron rays.
