Concrete Damage in Precast Reinforced Concrete Elements

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 1: Discoloration and air voids in a reinforced concrete wall (exposed concrete)

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig 2: Discoloration in a reinforced concrete wall (exposed concrete)

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 3: Fine cracks in a precast reinforced concrete wall

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 4: Crack and air voids in a reinforced concrete wall

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 5: Concrete damage on a precast reinforced concrete joist

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 6: Concrete damage on a wall component with lightweight wood wool panels for thermal insulation

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 7: Concrete surface severely damaged in the lower section by road salt and weathering

Figure: Prof. Dr.-Ing. Jürgen Vogel

Figure: Peri Vertrieb Deutschland

Fig. 8: Steel formwork

Figure: Peri Vertrieb Deutschland

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 9: Concrete wall constructed using formwork panels, with small voids visible on the concrete surface

Figure: Prof. Dr.-Ing. Jürgen Vogel

Fig. 10: Road bridge in Hanover temporarily supported with heavy-duty steel braces

Figure: Prof. Dr.-Ing. Jürgen Vogel

Precast concrete elements enable cost-effective and precise construction, but place high demands on materials, planning and execution. Damage such as cracks, spalling or corrosion can compromise the durability of the structure. This article examines typical causes of damage, modern concrete mixes, requirements for exposed concrete, as well as quality assurance procedures and concrete repair methods.

Causes and Manifestations

Concrete damage can result from several factors, including design, construction, and material defects, as well as chemical and physical influences. Common types of damage to concrete components include cracks, spalling, and corrosion of the reinforcement. Possible causes include, for example, an incorrect concrete mix design, inadequate compaction of the fresh concrete, or insufficient concrete cover, which leaves the reinforcing steel unprotected. Weather conditions such as freeze-thaw cycles, road salt, and aggressive pollutants in the air, as well as inadequate...