Due to the rapid depletion of natural resources, the use of waste materials and by-products from different industries of building construction has been gaining increased attention. Geopolymer concrete based on Pozzolana is a new material that does not need the presence of Portland cement as a binder. The main focus of this research is to produce lightweight geopolymer concrete (LWGPC) using artificial coarse lightweight aggregate which produced from locally available bentonite clays. In this investigation, the binder is low calcium fly ash (FA) and the alkali activator is sodium hydroxide and sodium silicate in different molarities. The experimental tests including workability, fresh density, also, the compressive strength, splitting tensile strength, flexural strength, water absorption and ultrasonic pulse velocity at the age of 7, 28 and 56 days were studied. The oven dry density and thermal conductivity at 28 days age are investigated. The results show that it is possible to produce high strength lightweight geopolymer concrete successfully used as insulated structural lightweight concrete. The 28-day compressive strength, tensile strength, flexural strength, dry density, and thermal conductivity of the produced LWGPC are 35.8 MPa, 2.6MPa, 5.5 MPa, 1835kg/m3, and 0.9567 W/ (m. K), respectively.

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In this paper, geopolymer lightweight aggregate pervious concrete (GPLWAPC) was studied. It utilized two ratios of blending, which are 1:4 and 1:5 (fly ash: local artificial coarse aggregate). The rough aggregates utilized were graded as well as made of single size. An optimal ratio of aggregates content was achieved via the technique of trial and error. The fly ash (FA) that was used was low calcium, while the alkali activating element represents sodium hydroxide (NaOH) along with sodium silicate (Na2SiO3) with proportion of 1:2.5. Mixture was made with alkaline liquid to fly ash 0.4 proportion, NaOH concentration of 16 molarity was used. The artificial graded coarse aggregate to fly ash proportion of 1:4 shows the highest compressive strength with 5.2 MPa at 7 days with density of 1340 kg/m3. Many experimental investigations on GPLWAPC were investigated; workability and the strengths of compressive and splitting tensile, at the age of 7, 28 and 56 day, were studied. Moreover, thermal conductivity and scanning electronic microscopy were examined at 28 day age for the same mixture.

On-site traditional methods to build items of homes with affordable prices are time-consuming. The adoption of ready and shaper technology, not only allows faster construction but also a better Economy. For many years Iraq engineering work for roof flatness used to use which is a square board with a length of 400, 600, or 1000mm, yet the procedure and the production need many improvements. One of the disadvantages of this production is the heavyweight and the big amounts of cement that need. So in this research, we made a trial to solve this difficulty using geopolymer concrete and lightweight artificial coarse aggregate. The article describes a new method used first time in Iraq based on the geopolymer concrete technique using fly ash as cementitious material and sodium silicate and hydroxide sodium as alkali-activated solutions and lightweight artificial coarse substances as aggregates enabling to produce lightweight tile. The produced tiles of research results have 35%, 50% less in weight, and thermal conductivity respectively than the normal tile which improved in Iraqi tiles and can be used for roof flatness.