Abstract
The increasing need to reduce the permanent weight of structural members forconstruction, especially for elegant and towering structures, to allow for long spans and less expensive foundations, has been a driving force in the quest to develop materials for such accomplishments. The GEM-TECH material is a foamed lightweight cementitious material made from mixing sand, cement, water and a GEM-SOL catalyst. The material has prospects of a lower CO2 emission from lower cement consumption, having light weight and lower cost of constituent materials, self-levelling and free-flowing with potential for structural use in construction. The material also has the potential of improved energy efficiency of a building as a result of reduced thermal conductivity like other foamed concretes.
This research investigates the structural performance of the GEM-TECH material by experimentally testing mechanical properties of the materials and then numerically exploring its structural behaviour by developing a finite element model that can simulate its behaviour using ANSYS software. Two sets of the GEM-TECH mixes with target densities of 1810 kg/m3 and 1600 kg/m3 were prepared and tested. The result from the experiment revealed that increasing the amount of GEM-SOL catalyst by 15% had improved the properties of the material such as its compressive (19% increase) and flexural strengths (30% increase). Compressive strength results from experiments for the mixes
with design densities of 1810 kg/m3 and 1600 kg/m3 (the former density chosen as it is close to the higher limit of density for lightweight concretes and the latter for comparison) fall into the LC16/18 and LC20/22 strength class based on British Standard classification for lightweight concretes. The material could be suitable for use as structural members in low strength structural applications or can complement normal weight concrete for higher
strength applications. The finite element model developed in the research showed good agreement with experimental tests results. Reinforced beams and slabs made from GEM-TECH material showed comparable flexural response to that of normal weight concrete of similar strength class in terms of failure load, however, the material offer less resistance to shear and crack propagation compared to normal weight concrete.
| Date of Award | Jun 2018 |
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| Original language | English |
| Awarding Institution |
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| Supervisor | Messaoud Saidani (Supervisor), Eoin Coakley (Supervisor) & Adegoke Olubanwo (Supervisor) |