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ﺑﺮرﺳﻲ اﺛﺮ ﺣﻔﺎﻇﺘﻲ ﭘﺎرﭼﻪﻫﺎی ﺗﺎری-ﭘﻮدی در ﺑﺮاﺑﺮ اﻣﻮاج اﻟﻜﺘﺮوﻣﻐﻨﺎﻃﻴﺲ
اﺳﻔﻨﺪﻳﺎر اﺧﺘﻴﺎری ، ﻣﺴﻌﻮد ﻟﻄﻴﻔﻲ ، ﺷﺒﻨﻢ آﻗﺎﻳﻲ
ﭼﻜﻴﺪه
اﻣﻮاج اﻟﻜﺘﺮوﻣﻐﻨﺎﻃﻴﺲ ﻣﺎﻧﻨﺪ آﻟﺮژیزاﻫﺎ در ﻋﻤﻠﻜﺮد ﺳﺎﻣﺎﻧﻪ دﻓﺎﻋﻲ ﺑﺪن اﺧﺘﻼل اﻳﺠﺎد ﻣﻲﻛﻨﺪ و ﺳﺒﺐ ﻓﺮاﺧﻮاﻧﺪن ﭘﺎﺳﺦﻫﺎی آﻟﺮژﻳﻚ و اﻟﺘﻬﺎﺑﻲ در ﺑﺪن ﺧﻮاﻫﺪ ﺷﺪ ﻛﻪ ﺑﺎﻋﺚ ﺗﺎﺛﻴﺮات ﺑﺴﻴﺎر زﻳﺎدی ﺑﺮ روی ﺳﻴﺴﺘﻢ ﻫﺎی ﻋﺼﺒﻲ، ﺑﻴﻨﺎﻳﻲ و ﺷﻨﻮاﻳﻲ اﻧﺴﺎن دارد و ﺑﺎ اﻓﺰاﻳﺶ درﺟﻪ ﺣﺮارت ﺑﺪن ﺑﺎﻋﺚ ﺑﺮوز ﺑﻴﻤﺎری ﻋﺎی ﻣﺨﺘﻠﻒ از ﺟﻤﻠﻪ ﺳﺮﻃﺎن ﻣﻴﺸﻮﻧﺪ. ﻳﻜﻲ از روش ﻫﺎی ﻣﻮﺛﺮ در ﺟﻠﻮﮔﻴﺮی از اﻧﺘﻘﺎل اﻳﻦ اﻣﻮاج ﺑﻪ ﺑﺪن اﻧﺴﺎن اﺳﺘﻔﺎده از ﭘﺎرﭼﻪ ﻫﺎﻳﻲ اﺳﺖ ﻛﻪ ﻧﻘﺶ ﻣﺤﺎﻓﻆ را دارﻧﺪ .
در اﻳﻦ ﺗﺤﻘﻴﻖ ﺑﻪ ﺑﺮرﺳﻲ اﺛﺮ ﭘﺎرﭼﻪﻫﺎی ﺗﺎری-ﭘﻮدی ﺑﺎ ﺳﺎﺧﺘﺎر وﻳﮋه (ﻓﻠﺰی) ﺑﺮ روی اﻣﻮاج اﻟﻜﺘﺮوﻣﻐﻨﺎﻃﻴﺲ و ﺗﺄﺛﻴﺮ ﻋﺎﻣﻞ ﻫﺎی ﻣﺨﺘﻠﻒ ﻣﺎﻧﻨﺪ ﺗﺮاﻛﻢ، ﺗﻌﺪاد ﻻﻳﻪﻫﺎ و ﻧﻮع ﻓﻠﺰ ﺑﺮ روی اﻣﻮاج ﺧﺮوﺟﻲ ﭘﺮداﺧﺘﻪ ﻣﻲ .ﺷﻮدﻧﺘﺎﻳﺞ ﺑﻴﺎﻧﮕﺮ آن اﺳﺖ ﻛﻪ ﺑﺎ اﻓﺰاﻳﺶ ﺗﺮاﻛﻢ و وﺟﻮد ﻓﻠﺰ اﺛﺮ ﺣﻔﺎﻇﺘﻲ ﭘﺎرﭼﻪ اﻓﺰاﻳﺶ ﻣﻲﻳﺎﺑﺪ و ﻣﻨﺎﺳﺐ ﺗﺮﻳﻦ ﭘﺎرﭼﻪ ﭘﺎرﭼﻪ ای اﺳﺖ ﺗﻚ ﻻﻳﻪ
/ 2 را دارد ﺑﺎ ﻓﻠﺰ آﻟﻮﻣﻴﻨﻴﻮم ﻳﺎ ﭘﺎرﭼﻪای اﺳﺖ ﺳﻪ ﻻﻳﻪ ﺑﺎ ﻓﻠﺰ ﻣﺲ ﻛﻪ ﺗﻮاﻧﺎﻳﻲ ﻣﺤﺎﻓﻈﺖ در ﺣﺪود 37 dB در ﻓﺮﻛﺎﻧﺲ 7MHZ
.
واژهﻫﺎی ﻛﻠﻴﺪی: اﻣﻮاج اﻟﻜﺘﺮوﻣﻐﻨﺎﻃﻴﺲ، ﭘﺎرﭼﻪ ﻣﺤﺎﻓﻆ، ﻓﺮﻛﺎﻧﺲ
ادامه مطلب ...
Effect of low modulus fibers on mechanical properties of mortars
B.Nasiri, A.Sadrmomtazi, R.Bakhoda, A.K.Haghi
Abstract
Cement-based materials, such as mortars and concretes are brittle in nature, with low bending strength and toughness. Therefore, the use of these materials in practice involves their combination with reinforcement, either as steel rods or with textiles. In this paper, nylon and polypropylene fibers were used in the form of short fiber and straight yarns in the various reinforcing ratio as reinforcement for the study on the efficiency of low modulus fibers on mechanical properties of mortars. The test results show that, reinforcement by textiles in the both form of short fiber and straight yarns improves the compressive and flexural performances of the cement mortars. The polypropylene fiber with higher length provides better performance in flexural strength increase. In comparison with straight yarns the contribution of chopped strands in strength of mortar was low. The values of flexural strength decreased with increasing the number of layer. Keywords: Cement mortars; Textile; Compressive strength; Flexural strength
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