Rockfall wire nettings
Rock-fall protection nettingRockfall Netting is defined as being rolls of heavily galvanized(or PVC coated heavily galvanized) steel wire mesh. This netting is used for protection against falling rock. The selvedges of the rockfall netting are the thicker edge wires to which the wire mesh is securely tied to withstand sudden or gradual stress.
Lacing wire is the wire used to joint the rockfall netting.
The cut edges of all mesh used in the construction of Rockfall Netting, except the bottom edges of end netting, shall be tightly selvedged with a wire having a diameter as shown in the table below.
The side selvedge of all and any mesh panels shall be woven integrally with the main mesh as described in the above clause 1.5 with a selvedge wire with the following diameter :
Selvedge wire diameter
Wire mesh shall be mechanically pre-fabricated to become a uniform hexagonal woven mesh wherein the joints are formed by twisting each pair of wires through three half-turns (commonly known as double twist), in such a manner that unraveling is prevented.
The tightness of the twisted joints shall be such that a force of not less than 1.7 kN is required when pulling on one wire to separate it from the other wire, provided each wire is prevented from turning under the applied forces, and the wire is all in the same plane.