KITUI SAND DAMS

5) Masonry comprising Hard core and mortar Substructure.After the foundation blinding slab sets and holds the columns firmly the foundationtrench is filled with masonry comprising clean hard core and mortar (1:4) Mortar forfilling should have more water (Sasol name) The joints between the rocks are filled25mm of this mortar. The rocks should be tapped well to settle completely to allvoids.When the filling reaches the level of the back flow, the construction of thebackflow should be done along side that of the wall as shown.PlanYTrench Where filling is done.River courseback flow trenchb) Section x-x (When back flow is on hard formation).X0.5mMasonry Comprising H/C and mortar (1:4)100m slab (1:3) with 12 strands of barbed wire.NB: The back flow for this site is resting on a formation that can support its weight.c) Section x-x (When the BF rests in a soft formation).It is usually not necessary to dig the whole depth of the trench at the back flow. It can beupto 0. 3m trench.47