Complete excavation with sloping sides

-Excavation for a basement on an open site can be carried out by cutting the perimeter back to the natural angle of repose of the soil .
-This method required sufficent site space around the intended structure for the over-excavation.
-No timbering is required
-In economic terms , the coasts of plant and manpower to cover the extra excavation , backfilling and consolidating must be offset by the savings made by omitting the temporary support works to the sides of the excavation.
-sometimes called open excavation


battered side excavation to safe angle repose

extra perimeter space required-restricts site space available for circulation , storage etc.

perimeter wedge of earth to be removed and after completon of the basement construction backfilled and consolidated