Ancillary construction work
Hawthorn hedging develops too much top growth and hence requires frequent cutting, otherwise it tends to develop tree-like trunks and loses its lower growth and, hence, its value as a hedge. The construction of brick walls is usually associated with road improvement schemes where the realignment of the carriageway causes existing walls to be demolished and new brick walls to be built along the altered frontages. A retaining wall may be of reinforced concrete, mass concrete, masonry or brick, but in every case its function is to resist the pressure exerted by the soil which it supports and to transfer this force on to the ground on which it is built. Great care must be taken in preparation and fixing of shuttering for concrete retaining walls. Reinforced concrete retaining walls use less concrete than the equivalent mass concrete walls, the steel reinforcement providing the structural strength of the walls.