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soundness test for cement-(Video-Youtube)

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Soundness test conducted in cement to verify that cement will not undergo a destructive expansion after setting. The expansion of restrained concrete members will result in severe tensile stresses that can result in cracking and spalling of casted concrete. The expansion could occur due to the reaction of free lime, magnesia, and calcium sulfate.  
Free lime found in the clinker. Free lime inter-crystallized with other compounds, and it tends to expand during the hydration process. The expansion of free lime is more than calcium oxide. Magnesia reacting with water similarly as calcium oxide does. But the crystalline formed due to the reaction of magnesia is deleteriously reactive, so it is unsound. Calcium sulfate can cause destructive expansion. The reaction of calcium sulfate will produce calcium sulfoaluminate (ettringite), which can result in the harmful expansion of cement. 
A soundness test will be conducted using La Chatelier's apparatus. For conducting this test, a cement sample of a specific consistency is prepared and placed inside the split cylinder. then, the cement is soaked in water for 24 hours. After 24 hours, the distance between indicator arms recorded (D1). Then the sample submerged in boiling water for one hour. The distance between the indicator arms recorded again (D2). The expansion is D2-D1. The cement expansion should fall within the specified value in project specifications or the local codes. 





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My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)