5.4.1 The manner of side and structural support may be of the following types :
1) Sloped back to a safe angle of repose as required by the soil conditions.
2) Shored by timber or steel support piles/ sheets, timbers should be close boarded and braced, sheet piles should be interlocked.
3) Provision of trench or drag boxes for trenching activities which are pulled along s the work progresses.