8/12/2019 132kv Scope.

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FOUNDATIONS

The requirements of 'Common Civil Works' shall apply.

3.1. TYPES AND USES

3.1.1 General

Where a tower location is in an area suitable for future development and theexisting ground level is below the probable level of ground when prepared fordevelopment the tower location is to be raised to this future level prior to anyinstallation work being started. The future level is to be assumed to be the surfacelevel of the adjacent highway asphalt. Raising of the level is to be done by theimportation, placement and compaction of properly graded rock, aggregates andfines to a standard suitable for the forming of the tower foundations which will beformed partly in the fill. Where appropriate the density and compaction of thematerial is to be tested to prove it meets the values assumed in the foundationdesign. The area of land to be raised will be that contained within a circle whosecenter is the center of the tower and whose circumference encloses the extremitiesof the soil frustums assumed in the foundation design plus an addition two metres ofwidth all round at the top of the batter.

Foundations for lattice steel towers for different classes of soil conditions shall be ofthe following approved types and shall be designated as specified that is, Types 1,2, 3, 4, 5 and 6 qualified by the arrangement under consideration, e.g., type 4 Piled,etc.

Class 1 : Anchor and MicropilesClasses 2 - 3 : Pad & ChimneyClasses 4 5 : PiledClass 6 : Piled - requiring special investigation

The type and design of foundation in each position shall be approved and shallmake adequate provision for horizontal shear forces at and below ground level.

Foundations for angle towers shall not have different designs for the compressionand tension legs, but shall be satisfactory for the most adverse condition ofmaximum and minimum angles of deviation and with the wind blowing from themost onerous direction.

Design methods and stresses not otherwise specified shall be in accordance withan approved Standard or Code of Practice.

3.2. DESIGN

3.2.1 Sub-soil Conditions

The Contractor shall ascertain that each foundation is suitable for the sub-soil andhe shall be responsible for any subsidence or failure due, in the opinion of theEngineer, to insufficient care having been taken either in the preliminary

examination of ground conditions or in the choice of installation of the foundation.The Contractor must satisfy himself about the general circumstances of all the sitesof the Works and the possibility of the subsidence and slips of soft ground, materialsand rock in or arising out of the Works. No authorised, approval or direction of theEngineer with regard to excavation or any matter or thing connected therein shall in