ﺗﻌﺘﺒﺮ اﻟﺨﺮﺳﺎﻧﺔ ﻣﺎدة اﻟﺒﻨﺎء اﻷوﻟﻰ، وﺻﻮرة اﻟﺘﻘﺪم اﻹﻧﺸﺎﺋﻲ ﻓﻲ اﻟﻌﺼﺮ اﻟﺤﺪﻳﺚ، وذﻟﻚ ﻟﺨﺼﺎﺋﺼﻬﺎ اﻟﺘﻘﻨﻴﺔ وﻣﺰاﻳﺎهﺎ اﻟﻔﻨﻴﺔ واﻹﻗﺘﺼﺎدﻳﺔ وإﺗﺴﺎع ﻣﺠﺎﻻت اﻹﺳﺘﻔﺎدة ﻣﻨﻬﺎ ﻓﻲ ﻣﺨﺘﻠﻒ اﻟﻈﺮوف واﻟﺤﺎﻻت، واﻟﺨﺮﺳﺎﻧﺔ ذات اﻟﻤﻮاﺻﻔﺎت اﻟﺠﻴﺪة، ﺗﻌﺘﻤﺪ ﺑﺎﻟﺪرﺟﺔ اﻷوﻟﻰ ﻋﻠﻰ ﻣﻄﺎﺑﻘﺔ ﻣﻜﻮﻧﺎﺗﻬﺎ اﻷﺳﺎﺳﻴﺔ آﺎﻹﺳﻤﻨﺖ واﻟﺮآﺎم واﻟﺮﻣﻞ واﻟﻤﺎء ﻟﻠﻤﻮاﺻﻔﺎت اﻟﻘﻴﺎﺳﻴﺔ وﺗﻌﺘﺒﺮ ﻣﻮاﺻﻔﺎت أﻋﻤﺎل اﻟ ﺨﺮﺳﺎﻧﺔ اﻟﺒﺤﺮﻳﺔ ﻋﻠﻰ درﺟﺔ آﺒﻴﺮة ﻣﻦ اﻷهﻤﻴﺔ، ﺑﺈﻋﺘﺒﺎر أن اﻟﻈﺮوف اﻟﺘﻲ ﺗﺘﻌﺮض ﻟﻬﺎ هﺬﻩ اﻟﺨﺮﺳﺎﻧﺔ ﻋﻠﻰ ﺟﺎﻧﺐ آﺒﻴﺮ ﻣﻦ اﻟﺼﻌﻮﺑﺔ، اﻷﻣﺮ اﻟﺬي آﺜﻴﺮا ﻣﺎ ﻳﺆدي ﺑﻬﺎ إﻟﻰ اﻟﺘﺼﺪع ﻓﻲ ﻓﺘﺮة زﻣﻨﻴﺔ ﻗﺼﻴﺮة ﻧﺴﺒﻴﺎ إذا ﻟﻢ ﺗﻜﻦ اﻟﻤﻮاﺻﻔﺎت اﻟﻤﺴﺘﻌﻤﻠﻪ ﻋﻠﻰ اﻟﻘﺪر اﻟﻤﻨﺎﺳﺐ ﻣﻦ اﻟﻜﻔﺎءة، وأن ﻳﻌﻘﺒﻬﺎ ﺑﻄﺒ اﻟﻤﻮاﺻﻔﺎت ﻴﻌﺔ اﻟﺤﺎل ﺗﻨﻔﻴﺬ ﻣﺘﻄﻠﺒﺎت هﺬﻩ . وﻗﺪ أدى واﻟﺘ اﻟﺘﻘﺪم اﻟﺒﺤﺮي ﻄﻮر ﻓﻲ ﺗﻘﻨﻴﺎت اﻟﻨﻘﻞ إﻟﻰ زﻳﺎدة اﻷهﻤﻴﺔ ﺑﺘﺤﻤﻠﻴﺔ اﻟﺨﺮﺳﺎﻧﺔ اﻟﺒﺤﺮﻳﺔ وﺧﺼﻮﺻﺎ ﻓﻲ اﻟﻤﻨﺎﻃﻖ اﻟﺼﺤﺮاوﻳﺔ وﺷﺒﻪ اﻟﺼﺤﺮاوﻳﺔ وﻗﺪ ﻣﻠﺤﻮ ﺷﻬﺪت اﻟﻤﻨﺸﺂت اﻟﺒﺤﺮﻳﺔ ﻓﻲ ﻟﻴﺒﻴﺎ وﺧﺼﻮﺻﺎ اﻟﻤﻮاﻧﺊ ﺗﻄﻮرا اﻷ ﻇﺎ ﺧﻼل اﻟﻌﻘﻮد اﻷرﺑﻌﺔ ﺧﻴﺮة، وآﺎن ذﻟﻚ ﻧﺎﺗﺠﺎ ﻣﻦ إآﺘﺸﺎف اﻟﻨﻔﻂ واﻟﻐﺎز، واﻟﻨﻤﻮ اﻹﻗﺘﺼﺎدي اﻟﺴﺮﻳﻊ اﻟﺬي ﺷﻬﺪﺗﻪ اﻟﺒﻼد ﺧﻼل اﻟﻔﺘﺮة اﻷﺧﻴﺮة ﻣﻦ ﺟﻬﺔ، واﻟﺤﺎﺟﺔ إﻟﻰ إﻧﺸﺎء وﺗﺤﺪﻳﺚ ﺑﻨﻴﺔ ﺗﺤﺘﻴﺔ ﺗﺨﺪم ﻣﺘﻄﻠﺒﺎت ﺣﺮآﺔ اﻟﻨﻘﻞ واﻟﻤﻮاﺻﻼت وﺗﻼﺋﻢ اﻟﻤﻮﻗﻊ اﻟﺠﻐﺮاﻓﻲ ﻟﻠﻴﺒﻴﺎ ﻣﻦ ﺟﻬﺔ أﺧﺮى وﻧﻈﺮا ﻟﻺهﺘﻤﺎم اﻟﻤﺘﺰاﻳﺪ ﺑﺎﻟﺨﺮﺳﺎﻧﺔ ﻓﻲ ﻟﻴﺒﻴﺎ ﺧﻼل اﻟﻔﺘﺮة اﻷﺧﻴﺮة وﺧﺼﻮﺻﺎ اﻟﺨﺮﺳﺎﻧﺔ اﻟﺒﺤﺮﻳﺔ، وﻟﻘﻠﺔ اﻟﺪراﺳﺎت اﻟﺨﺎﺻﺔ ﺑ ﺎﻟﻤﻮاد اﻟﻤﺴﺘﺨﺪﻣﺔ ﺑﻬﺎ، وﺣﻴﺚ أن ﻣﺸﻜﻠﺔ ﺻﺪأ ﺣﺪﻳﺪ اﻟﺘﺴﻠﻴﺢ أﺿﺤﺖ ﻣﻦ اﻟﻤﺸﺎآﻞ اﻟﻜﺒﻴﺮة ﻣﺤﻠﻴﺎ وﻋﺎﻟﻤﻴﺎ ﻣﻦ ﺣﻴﺚ ﺗﺄﺛﻴﺮهﺎ ﻋﻠﻰ ﺛﺒﺎت اﻟﻤﻮاد وﺳﻼﻣﺔ اﻟﻌﻨﺎﺻﺮ اﻹﻧﺸﺎﺋﻴ ﺔ اﻟﻤﻨﻔﺬة ﺑﺎﻟﺨﺮﺳﺎﻧﺔ اﻟﻤﺴﻠﺤﺔ، وﺧﺎﺻﺔ ﻓﻲ ﻣﻨﺎﻃﻖ ﻣﺘﻌﺮﺿﺔ و ﻟﺒﻴﺌﺔ ﺷﺪﻳﺪة، أ ن اﻟﺘﺪهﻮر واﻹﺟﻬﺎدات اﻟﻤﺘﺮﺗﺒﺔ ﻣﻦ ﺻﺪأ ﺣﺪﻳﺪ ﻣﻠﺨﺺ اﻟﺪراﺳﺔ اﻟﺘﺴﻠﻴﺢ ﻳﻤﻜﻦ ﻟﻬﺎ أن ﺗﻨﻘﺺ ﻣﻦ اﻟﻌﻤ و ﺮ اﻟﺘﺼﻤﻴﻤﻲ واﻟﺨﺪﻣﻲ ﻟﻺﻧﺸﺎءات، ﺗ وإﺳﺘﻘﺮا ﺆﺛﺮ ﻋﻠﻰ ﻣﻘﺎوﻣﺘﻬﺎ ر هﺎ وأﻣﺎﻧﻬﺎ وﻓﻲ اﻟﺤﻘﻴﻘﺔ ﻳﻤﻜﻦ أن ﺗﻘﻮد إﻟﻰ إﻧﻬﻴﺎر ﻣﺒﻜﺮ .وﻗﺪ أﺟ ﺮﻳﺖ هﺬﻩ اﻟﺪراﺳﺔ وهﻲ ﺗﺘﻨﺎول ﻣﺮاﺟﻌﺔ ﻋﺎﻣﺔ ﻟﺘﻘﻴﻴﻢ ﺟﻮدة اﻟﺨﺮﺳﺎﻧﺔ ﺑﺎﻟﻤﻨﺸﺂت اﻟﺘﻲ ﺗﻢ ﺗﻨﻔﻴﺬهﺎ ﻓﻲ ﺑﻌﺾ اﻟﻤﻮاﻧﺊ اﻟﻠﻴﺒﻴﺔ، ﺣﻴﺚ ﺗﻢ إﺟﺮاء ﺑﻌﺾ اﻹﺧﺘﺒﺎرات ﻏﻴﺮ إﺗﻼﻓﻴﺔ ﻧﻈﺮا ﻟﺨﺼﻮﺻﻴﺔ اﻟﺨﺮﺳﺎﻧﺔ اﻟﺒﺤﺮﻳﺔ ﻋﻦ ﻏﻴﺮهﺎ ﻣﻦ ﺣﻴﺚ ﻃﺮق اﻹﻧﺸﺎء واﻟﻈﺮوف واﻟﺒﻴﺌﺔ اﻟﻤﺤﻴﻄﺔ .إﺧ وﻗﺪ ﺗﻢ ﻓﻲ هﺬﻩ اﻟﺪراﺳﺔ ﺘﻴﺎر ﺧﻤﺲ ﻣﻮاﻧﺊ ﺗﺠﺎرﻳﺔ وﺻﻨﺎﻋﻴﺔ ﻋﻠﻰ ﻃﻮل اﻟﺴﺎﺣﻞ اﻟﻠﻴﺒﻲ وهﻲ ﻣﻴﻨﺎء ﻃﺮاﺑﻠﺲ اﻟﺘﺠﺎري واﻟﺼﻠﺐ وﻣﻴﻨﺎء ﻣﺼﺮاﺗﻪ اﻟﺘﺠﺎري، وﻣﻴﻨﺎء اﻟﺤﺪﻳﺪ ، ﺑﻤﺼﺮاﺗﻪ اﻟﺒﺤﺮي . وﻣﻴﻨﺎء اﻟﺒﺮﻳﻘﺔ اﻟﺼﻨﺎﻋﻲ واﻟﺘﺠﺎري، ورﺻﻴﻒ أﺑﻮآﻤﺶ ،ﺧﻤﺲ ﺣﺎﻻت ﻣﻦ اﻟﻤﻮاﻧﺊ اﻟﺘﺠﺎرﻳﺔ واﻟﺼﻨﺎﻋﻴﺔ ﺗﻢ دراﺳﺘﻬﺎ وﻣﺮاﺟﻌﺔ ﺑﻌﺾ اﻟﺪراﺳﺎت اﻟﺘﻲ أﺟﺮﻳﺖ ﻋﻠﻴﻬﺎ، وﺗﻘﻴﻴﻢ ﻧﺘﺎﺋﺞ اﻹﺧﺘﺒﺎرات اﻟﺘﻲ ﺗﻢ إﺟﺮاؤهﺎ، وﻣﻨﺎﻗﺸﺔ اﻟﺘﺪهﻮر اﻟﺨﺮﺳﺎﻧﻲ اﻟﺬي وﺻﻞ ﻓﻲ اﻟﺒﻌﺾ ﻣﻨﻬﺎ إﻟﻰ ﻣﺮﺣﻠﺔ ﺧﻄﻴﺮة ﻓﻲ ﻓﺘﺮة زﻣﻨﻴﻪ ﻗﺼﻴﺮة ﻧﺴﺒﻴﺎ، آﻤﺎ ﺗﺒﺮز اﻟﺪراﺳﺔ اﻟﻌﻮاﻣﻞ اﻟﺮﺋﻴﺴﻴﺔ اﻟﺘﻲ ﺗﺆﺛﺮ ﻋﻠﻰ ﺗﺤﻤﻠﻴﺔ اﻟﺨﺮﺳﺎﻧﺔ ﻓﻲ اﻟﺒﻴﺌﺔ اﻟﺒﺤﺮﻳﺔ وﺗﺘﺤﺮى ﻣﺪى اﻟﺘﻘﻴﺪ واﻹﻟ ﺑﺎﻟﻤﻮاﺻﻔﺎت ﺘﺰام وﻓﻲ اﻟﺨﻼﺻﺔ ﺗﻘﺪم اﻟﺪراﺳﺔ ﺑﻌﺾ اﻟﺘﻮﺻﻴﺎت ﻟﺘﺤﺴﻴﻦ اﻟﻤﻮاﺻﻔﺎت اﻟﻤﺤﻠﻴﺔ ﻟﻠﺨﺮﺳﺎﻧﺔ اﻟﺒﺤﺮﻳﺔ، واﻟﺘﻲ ﺗﺘﻌﻠﻖ ﻟﻺﺳﻤﻨﺖ w/c ﺑﺸﻜﻞ رﺋﻴﺴﻲ ﺑﻤﻌﺪل اﻟﻤﺎء وﻧﻮع وآﻤﻴﺔ اﻹﺳﻤﻨﺖ، واﻟﻐﻄﺎء اﻟﺨﺮﺳﺎﻧﻲ واﻟﻤﻌﺎﻟﺠﺔ، ، وﺗﻘﺪم أﻣﺜﻠﺔ ﻋﻠﻰ ﺗﺄﺛﻴﺮ اﻟﺒﻴﺌﺔ واﻟﺘﺤﻜﻢ ﺑﺠﻮدة اﻟﺨﺮﺳﺎﻧﺔ ﺑﺎﻟﻤﻨﺸﺂت واﻟﺴﺎﺣﻠﻴﺔ اﻟﺒﺤﺮﻳﺔ.
عبد الله عمر الشكري (2010)

Abstract Behavior of constant thickness circular plates under axisymmetric uniform loading and for different edge boundary conditions may be obtained analytically, but for the case of variable thickness and transverse shear effect is usually difficult to follow analytically. Since the numerical analysis has become an essential tool in engineering mechanics, where the use of numerical methods enables the engineer to expand his or her ability to solve practical design problems, where the engineer may now treat real shapes as distinct from the somewhat limited variety of shapes amenable to simple analytic solution. That is why developing an appropriate numerical analysis becomes a more suited procedure to solve such problems. The standard stiffness procedure of finite element method may encounter some difficulty in formulation when dealing with both cases of variable thickness and transverse shear effect. The usually followed procedure is to utilize ring elements of constant thickness and increase the number of elements to reach an accurate solution. Mixed finite element formulation utilizing curved ring element with linearly varying thickness as well as considering the shear effect has proved to be successful to obtain accurate results for shells of revolution with small number of elements, due to the fact that the mixed formulation allows for nodal values in the form of global displacement components (ur, uz) and bending moment (Mr, M) as field variables, where second order polynomials may be used allowing for shear deformation effect to be considered as a function of moments and does not require higher order polynomials.
ايناس عبدالمولي المصراتي (2009)

Different types of concrete mixtures are used as building materials. The manufacturing process of two-stage concrete (TSC) differs from that of conventional concrete. This study investigated conventional mechanical properties derive empirical relations for estimation of the mechanical parameters of TSC and conventional concrete mixtures. TSC was used to prepare 216 specimens and conventional concrete was used to prepare 108 specimens that then were aged for 28 days. Uniaxial compression, Brazilian tensile strength, and point load tests were carried out as destructive testing. Schmidt hammer and ultrasonic pulse velocity tests were carried out as nondestructive testing. The data from testing were categorized as regression or test data. Empirical relations were derived between the parameters for the two types of concrete, and these relations were validated. It was concluded that indirect, nondestructive testing of engineering materials, including concrete, considerably increases the speed and decreases the estimation cost of determining the mechanical parameters. This method can be recommended for estimation of these mechanical parameters. arabic 13 English 97
Hakim S. Abdelgader(7-2020)