An investigation of the effect of walnut shell as sand replacement on the performance of cement mortar subjected to elevated temperatures

Abstract

This study examined the effect of ground shells of walnut (GW) as fine aggregate on the fresh and hardened properties of cement mortar before and after being subjected to elevated temperatures. The experimental work consists of two series with different water to cement ratio (w/c) and various percentages of GW. In each series, the ratios of GW were varied in range (0-30% at an increment of 10%). The fresh density and slump test were used as fresh properties and the dry density with compressive strength were measured at the curing ages of 7, 14 and 28 days as hardened characteristics. Also, the dry density and compressive strength at 28 days curing age were examined after exposure to an elevated temperature of 400 °C and 600 °C for two hours. The results indicated that the all tested properties were reduced by using GW. The optimum utilized ratio of GW is 20% for the first series with w/c of 0.5 which led to producing lightweight cement mortar and is suitable for structural purposes before and after exposure to 400 °C. However, the rest of the mixtures are suitable for non-structural purposes.

Investigation the effect of nanocarbon tube prepared from tea waste on microstructure and properties of cement mortar

“…This tendency is self-explanatory, since there is a notable disparity between the density of nano carbon tube produced from tea waste and the mortar's primary materials (Zhang et al 2019;Cao et al 2021;Horma et al 2022). These ndings are also consistent with those of prior investigations, which explored a reduction in the dry density of mortar samples (Parveen et al 2015;Mohammed et al 2021).…”

Synergic effect of metakaolin and groundnut shell ash on the behavior of fly ash-based self-compacting geopolymer concrete

“…To tackle the problem of global warming, the world has made tremendous efforts to decrease the use of PC. These include the disposal of waste by-products by recycling these waste materials and the development of alternative binders for PC [6][7][8].The use of industrial/agricultural waste by-products like wheat straw ash (WSA) [9], coconut shell ash [10], ground granulated blast furnace slag (GGBFS) [11], wheat straw ash (WSA) [12], eggshell ash [13], metakaolin (MK), corn cob ash (CCA), millet husk ash (MHA) [14,15], açaí natural fibre [16], palm oil fuel ash [17], rice straw and cotton stalk [18], glass fiber [19], ceramic wastes [20], plastic waste [21], seashell [22], rubber [23] and other pozzolanic materials can assist in decreasing the requirement for PC in concrete, hence reduce the carbon dioxide discharges [2,24,25]. The addition of fly ash (FA) to concrete can significantly improve many of the properties of fresh and hardened concrete.…”

The behavior of sustainable self-compacting concrete reinforced with low-density waste Polyethylene fiber

“…Concrete has an extensive environmental impact, such as landfills, sea and air pollution [1][2][3]. Therefore, recycling the concrete materials wastes is of significant importance [4,5].…”