Vertical or inclined trench wall anchors - use tensioned tie rods with mushroom head, spaced to suit maximum permissible shear stess

摘要

Trench walls which are fastened from behind by ties, use anchors whether the trench wall is vertical or inclined. The ties are almost perpendicular to the wall and are tightened to a predetermined tension. The concrete is applied by a spray gun. The anchors also have precast reinforced concrete elements forming a mushroom head on the end of the ties. they only cover a fraction of the total surface area which is to be reinforced and it is on these elements that the pull of the ties is exerted. The ties are positioned so that the trench wall in between the anchor heads is able to resists the shear stress. The edges of the mushroom heads are chamfered, and the surface of the concrete has corresponding locating grooves for the heads.