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A high proportion of damp problems in buildings are caused by ambient climate dependent factors of condensation and rain penetration. [1] Capillary penetration of fluid from the ground up through concrete or masonry is known as "rising damp" and is governed by the shape and porosity of the construction materials through which this evaporation ...
Water continues to permeate into the region. As the soluble substance dissolves under the paint layer, the pressure caused by the increase in volume can exert a greater force than the paint adhesion and cohesion forces, giving rise to the formation of a blister; the process called osmotic blistering.
If concrete is exposed to very high temperatures very rapidly, explosive spalling of the concrete can result. In a very hot, very quick fire the water inside the concrete will boil before it evaporates. The steam inside the concrete exerts expansive pressure and can initiate and forcibly expel a spall. [23]
Frost damage can occur as cracks, stone splinters and swelling of the material. When water freezes, the volume of water increases by 9 %. [citation needed] When the volumetric moisture content exceeds 91 %, then the volume increase of water in the pores of the material caused by freezing cannot be absorbed by sufficient empty pores. This causes ...
The water diffusion time is thus proportional to the square of its transport distance. As a consequence, the water saturation degree inside thick concrete structures often remains higher than 80%, a level sufficient to provide enough water to the system and to maintain the alkali-silica reaction on going.
Weathering carbonation occurs in concrete when calcium compounds react with carbon dioxide (CO 2) from the atmosphere and water (H 2 O) in the concrete pores. The reaction is as follows. First, through chemical weathering, CO 2 reacts with water in the concrete pores to form carbonic acid: CO 2 + H 2 O ⇌ H 2 CO 3
When it reacts with concrete, it causes the slab to expand, lifting, distorting and cracking as well as exerting a pressure onto the surrounding walls which can cause movements significantly weakening the structure. Some infill materials frequently encountered in building fondations and causing sulfate attack are the following: [2] Red Ash
Robotic Hydrodemolition in Folkestone, UK. Hydrodemolition of concrete exposing the rebar.. Hydrodemolition (also known as hydro demolition, hydroblasting, hydro blasting, hydromilling, waterblasting, and waterjetting) is a concrete removal technique which utilizes high-pressure water, often containing an abrasive material, to remove deteriorated and sound concrete as well as asphalt and grout.