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lightweight Concrete

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Lightweight concrete made simply by using lightweight aggregates. Lightweight aggregates are produced by expanding shale, clay, and slate. These aggregates are manufactured in high-temperature rotary klin. During the production, gas bubbles are formed inside the aggregates and remain after cooling. These bubbles will reduce the weight of aggregates without reducing strength.
Figure 1
The using of lightweight concrete is limited due to cost and durability concerns. Despite the limited use of lightweight concrete, many structures around the world are built using lightweight concrete. 

Using lightweight concrete to construct a building will significantly reduce the dead load. Cutting the dead loads means reducing the size of foundations. For precast elements. Using lightweight concrete will reduce the weight of prefabricated elements and facilitate the handling, shipping, and erection of members. Lightweight concrete can be used to increase the span length and rehabilitate old structures. replacing normal aggregates with lightweight aggregates can be done using one of the following methods

  •  All lightweight: All aggregates (coarse and fine) are made up of lightweight materials.
  • Sand lightweight: Lightweight coarse aggregate with normal-weight fine aggregate.
  •  Specified density: A blend of lightweight and normal-weight aggregates to achieve a target density.

Another benefit of using lightweight aggregates is internal curing. Lightweight aggregates can be wetted before mixing with other concrete mix ingredients. Lightweight aggregates will absorb a higher amount of water than normal-weight aggregates. Once the hydration process begins. The moisture inside the aggregates will leave and contribute in the hydration process. Several tests conducted in concrete mixed with pre-wetted lightweight aggregates have shown reducing permeability and shrinkage of concrete. Internal curing will help in reducing the time of external curing. 



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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)