General Information

Figure 1 shows the construction site of a pavilion.

Pavilion.
Construction site of a pavilion

The project consists of building several pavilions alongside a lake. A pavilion consists of four reinforced concrete columns, two benches, and a Dutch gable roof. The distance between the reinforced concrete columns l ≅ 3.5 m, and the distance w ≅ 2.5 m.

Bench Concept

Figure 2 shows a bench under construction.

Bench formwork and reinforcement.
Formwork and reinforcement of an RC bench

The bench consists of three legs (1 to 3) and a seat. The end legs (1 and 3) are made of autoclaved aerated concrete (AAC) blocks and concrete, which is poured into the space between the AAC blocks and the RC columns; the central leg (2) is made of AAC blocks. The seat reinforcement consists of longitudinal and transverse rebars with 90-degree bent ends (bottom reinforcement only). The longitudinal rebars are placed directly (without cover) over the formwork panels and have a bigger diameter and a shorter spacing than the transverse rebars, which are placed directly over the longitudinal ones. Figure 3 shows an end leg region.

End leg.
Leg region of a reinforced concrete bench

The RC columns are connected by direct contact.

  • Does the reinforcement have any problems?
  • Figure 4 shows the pavilion during construction with finished benches.

    Pavilion with finished benches.
    Pavilion with reinforced concrete benches

    New Bench Concept

    The bench concept was changed; all pavilions were demolished until the foundation, as shown in figures 5 and 6.

    Pavilion during demolition works.
    Pavilion during demolition works
    Pavilion after demolition works.
    Pavilion after demolition works
  • What are some possible reasons to change the project during the construction phase?
    How many resources are used for the construction of the pavilions and their demolition until the foundations?
  • Figure 7 shows the construction site of a new pavilion.

    Pavilion.
    Construction site of a pavilion

    The new bench consists of two legs (the columns) and a seat made of reinforced concrete. The seat has an asymmetric inverted U-like shape and is connected to the legs by rebars. Figure 8 shows a finished bench.

    New RC bench.
    Pavilion with reinforced concrete benches

    The cross-section shape of the seat is shown in yellow. Figure 9 shows a new pavilion with the steel roof structure.

    New pavilion with steel roof structure.
    Pavilion with RC benches and steel roof structure

    The RC columns are partially confined with AAC blocks.

  • What are some possible reasons to use reinforced concrete benches instead of timber or steel benches?
    Does the pavilion have a structural safety or serviceability problem without the AAC blocks?