Because of the change in operation and use, the construction should be retrofitting in 2011. To this end, the construction structure (except the A area) was fully tested. The results are as follows:

• B area: building area of 57 thousand m2, after testing: some reinforced concrete beams and columns do not meet the requirements, a small amount of structural strength is still lower than the design grade, must be partially reinforced.

  
  

• C area: the building area is 83 thousand m2. After testing, some reinforced concrete columns and beams are lower than the design strength grade 1, 3 floor is lower than grade 2.

  
  

• After testing the concrete strength of some beams of each layer, except the detection value of the underground layer is presumed to be 25.0MPa, the difference of the other layers is more than 5.5MPa, so it is not presumed, and the strength grade is the lowest C40 concrete. The value is only 19.8MPa.

  
  

• The axial compression ratio and reinforcement of some columns do not meet the requirements of 8 degree seismic fortification in Beijing area. Therefore, the testing unit recommends that all components should be comprehensively tested.  In addition to the D1 area (building area 43 thousand m2) and D2 area (construction area 37 thousand and 500 m2), the testing units suggest that the seismic reinforcement and the bearing capacity reinforcement of the components be strengthened.

Strengthening reinforced concrete(RC) column

There are two methods for the consolidation and mining of steel reinforced concrete column

 (1) In the original steel reinforced concrete column Angle corners of outsourcing;

 (2) Increase the cross-sectional area of steel reinforced concrete column.

Strengthening reinforced concrete(RC) beams

 (1)Cross section of a cantilever beam

 (2)Sticking steel plate on top of the cantilever beam

 (3)Cross section of positive cross section beam

 (4)Inclined cross section of beam with carbon fiber reinforced wrap