LIGHTWEIGHT MORTAR GEOPOLIMER BASED ON FLY ASH AND PALM ASH

This research discusses the use of alumunium powder in the manufacture of geopolymer mortar made from fly ash and palm ash, with the aim of knowing the optimal amount of alumunium powder mixture against the compressive strength of geopolymer mortar. The research method used experimental methods in the laboratory, to examine the compressive strength of different geopolymer mortar tests used in the form of cubes measuring 5 x 5 x 5 cm with a mixture composition of NaOH: Na2SiO3 = 1: 2.5, Activator: Precursor = 1: 1, Fine Aggregate: Precursor = 1.5: 1 Concentration of NaOH = 12 M for the ratio of fly ash use: palm ash = 75: 25% using alumunium powder as much as 0, 0.5, 0.75 and 1%. Mortar strength testing was carried out after 3, 7, 14, 21 and 28 days of maintenance The compressive strength results obtained in each composition of the geopolymer mortar mixture are for geopolymer mortar without a mixture of alumunium powder as large as Mpa, for geopolymer mortar with a mixture of alumunium powder as much as 0.5%, 0.75% and 1% have a compressive strength of 20.9 Mpa, 15.2 Mpa, 12.7 Mpa Dan 9,7 Mpa

A Review of Lightweight Composite Development Using Paper Waste and Pulverized Ceramics - Towards a Sustainable and Eco-Friendly Construction

Finding an effective framework for the consumption of municipal and construction/demolition wastes has been the main research consideration for decades. For different categories of wastes, there is a need for the development of working systems for cleaner utilization of the materials. This study is focused on the review of composite development using paper waste and pulverized ceramics. The issues discussed comprises; excessive waste production, the building sector’s ecological effects, paper waste availability, and proposed solutions to realizing a sustainable built environment. The study also discussed standard mortar and the various types that exist, lightweight mortar, its nature, intricacies of its production process, and the prior use of waste materials for its manufacture. Paper waste, although not having enough strength as conventional aggregate, but with its filling effect, could fit lightweight mortar production along with other similar aggregates. The study gave an overview of the methodological deficiency found and proposed viable approaches to combat these gaps and further advance sustainable and eco-friendly construction.

Residual TRM-to-Concrete Bond after Freeze–Thaw Cycles

In the present work, the effect of various freeze–thaw cycles (namely, 0, 10, 30, 50, 60, and 70) on the residual bond characteristics of textile reinforced mortar (TRM)-to-concrete was experimentally examined. The TRM consisted of a carbon dry fiber textile embedded in a cement-based matrix. Two mortar types were used as the matrix: a normal-weight and a lightweight one sharing the same hydraulic powders but different aggregates (limestone and pumice sand, respectively). The single-lap/single-prism set up was applied after the specimens underwent hygro-thermal treatment (according to ASTM C 666-Procedure B). Failure was due to the sleeve fibers rupturing the load aligned yarns or textile slippage from the mortar for an exposure period ranging between 0 and 60 cycles and to TRM debonding from the substrate for 70 cycles. Increasing cycles resulted in the intensification of partial interlaminar debonding phenomena and the weakening of the textile-to-matrix bond, with lightweight mortar being more prone to these effects. In the absence of a commonly accepted standardized method for the assessment of the freeze–thaw resistance of cement-based composites, the criterion for the termination of the freeze–thaw sequence was the number of cycles inferring a shift in failure mode (from fiber rupture/fiber slippage to TRM debonding from the substrate).

Interlayer Reinforcement Combined with Fiber Reinforcement for Extruded Lightweight Mortar Elements

Lightweight mortar extrusion enables the production of monolithic exterior wall components with improved thermal insulation by installing air chambers and reduced material demand compared to conventional construction techniques. However, without reinforcement, the systems are not capable of bearing high flexural forces and, thus, the application possibilities are limited. Furthermore, the layer bonding is a weak spot in the system. We investigate a reinforcement strategy combining fibers in the mortar matrix with vertically inserted elements to compensate the layer bonding. By implementing fibers in the extruded matrix, the flexural strength can be increased almost threefold parallel to the layers. However, there is still an anisotropy between the layers as fibers are oriented during deposition and the layer bond is still mainly depending on hydration processes. This can be compensated by the vertical insertion of reinforcement elements in the freshly deposited layers. Corrugated wire fibers as well as short steel reinforcement elements were suitable to increase the flexural strength between the layers. As shown, the potential increase in flexural strength could be of a factor six compared to the reference (12 N/mm2 instead of 1.9 N/mm2). Thus, the presented methods reduce anisotropy in flexural strength due to layered production.