Tower structure Design Specs
5.1.1 Square GSM Self supporting steel tower of height 20m and above:
5.1.2 Square telecommunication lattice tower of height 15m and below:
A hot dipped galvanized steel cable ladder should be installed between the telecommunication lattice tower and the container or outdoor cabinets to support the coaxial cables. Steel cable ladders should be delivered & installed between the shelter and tower. The cable ladder shall be 400mm minimum width with horizontal rungs spaced at 500mm maximum. The cable ladder profile shall be of shape and size to provide fixing arrangement for standard cable clamps such as Andrew, FEMA, RBS or other acceptable clamps for cable sizes of ½” through 1⅝”.
The cable ladder shall be delivered complete with all nuts, bolts, and clamps. The cable ladder shall be supported by hot dipped galvanized steel vertical adjustable (telescopic) supports having precast reinforced concrete foundations on the ground with minimum 20cm buried under the ground.
If requested by Omantel, the cable ladder shall be covered with a hot dipped galvanized steel cover, (to prevent damage to the cable) suitably fixed to the cable ladder.
The distance between the tower & the container is normally kept minimum; however the contractor is obliged to provide cable ladder in-between the GSM Self supporting steel tower & container regardless of the distance. In addition, the cable ladder should be designed, manufactured & installed in such a way that the unsupported length shall not exceed 3 meters in order to avoid bending under the weight of the cables.
The vertical feeder supports shall be provided adjacent to the climbing ladder capable of supporting maximum number of feeders for the ultimate system. The spacing between feeder support bars shall not exceed 0.8 meter. The vertical cable support shall not obstruct the feet of the climbing person; therefore the minimum distance from the climbing ladder to the support shall be 0.25 meter.
Climbing ladders (and vertical cable supports) shall be fixed at the nearest leg of the telecommunication lattice tower to the shelter and it should comply with local & international safety standards and specifications with regard to their dimensions, mounting, material, etc.
The connection bolts, nuts and washers will be according to any of the following standards (or equivalent):
Mechanical properties of fasteners
prEN 781/2 Hexagon bolts for high strength structural bolting
prEN 784/5 Plain washers for high strength structural bolting
EN 24014 Hexagon head
Strength class 8.8
The nuts will be locked so that they won’t get loose during the operation. The proper tightening torque will be defined in the document
Dimensional standards for fasteners
DIN 7990, 6914, 933, 607, 6921, 931, 960 961
DIN 555, 7967, 934, 6915, 439-2
DIN 7989, 6916, 126, 434
DIN 127, 128
As per requirements
The work platform should be equipped with a top handrail of tubular or angle profile, galvanized steel. The safety railing is capable of carrying a 1kN concentrated load. There is an intermediate rail at a height of 0.6m. A kick plate (toe board) 0.1m in height is installed around the platform to prevent tools or other objects from falling from the tower.
The Aircraft Warning System of the telecommunication tower should be designed, supplied & installed according to AWL Standards & Specifications that are described in documents