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Article Incorporation of river silt in ceramic tiles and bricks

Thank you, sir. But, my specific question was when we have soil-cement blocks.

Hello Ashwin,

Understanding the behaviour of silt may help us to understand its suitability in a soil-cement block. Silt is basically a fine-grained soil component that in most cases does not exhibit plasticity and thus can be classified as an inert material. Since it cannot exhibit plasticity, it cannot act as a binder as clays do. On other hand, the particle size of silt is less than that of sand (75micron to 2 micron). Since the particle size is so less, there is less frictional resistance which it can provide in comparison to sand. Hence, its contribution to the overall strength will also be less. Additionally, with a higher surface area than other inert granular material in the block and by limiting the clay content in the block, you would require higher quantities of cement to provide necessary bonding between the silt particles. Practically, silt can act only as a filler in a soil-cement block filling up the pores which sand or gravel cannot do. Hence, only a limited percentage of silt can be used in the block, provided it is stabilised properly.

I hope this answer helps you in any way.

Regards,

Sravan