General Information

Figure 1 shows a covered sports tribune.

Covered sports tribune.
Covered sports tribune made of precast segmental concrete beams

The roof structure consists of prestressed concrete, steel roof bracing, purlins, and metal roofing sheets.

Concrete Cracks

Figure 2 shows a schematic cross-section of the structure.

Covered sports tribune.
Cross-section of a covered sports tribune

The maximal cantilever arm a ≅ 27 m. The cracks are located in the top back junction region of the roof structure. Figure 3 shows a back view of the covered sports tribune.

Covered sports tribune (back view)
Back view of a covered sports tribune

The red circles mark the locations of the cracks. Location A is shown in figure 4.

Location A
Concrete cracks of a covered sports tribune

There are two horizontal cracks, and water leakage from crack 2 is noticeable. Two further crack locations viewed from the side are shown in figures 5 and 6.

Concrete cracks
Concrete cracks of a covered sports tribune

There are one vertical and two horizontal cracks.

Concrete cracks
Plants growing out of a concrete crack

There is one horizontal crack with plants growing out of it.

  • What are some possible reasons for the above shown cracks?
    What are the structural consequences?