Comprehensive assessment of the floor slab technical condition of the medical and diagnostic complex building of the hospital "OKHMATDIT"

Abstract

This paper contains research results of the monolithic reinforced concrete 8th-floor slab of the block B of the object "Modern medicaldiagnostic complex of the National Children's Specialized Hospital "OKHMATDIT" in Kyiv". The need to research the 8th-floor slab technical condition is due to the fact that as a result of poor quality work associated with the violation of technological standards for winter concrete works, the floor slab defects that significantly reduce the loadbearingcapacity of the slab and prevent further works tocomplete the block B and put it into operation.The floor slab technical condition assessment had performed by methods of visual and instrumental investigation. During a visual investigation,numerous manufacturing defects of the monolithicreinforced concrete 8th-floor slab had been located, such as local destruction of concrete cover, corrosion, and uncovering of reinforcement. The real concrete strength of the 8th-floor slab has beendetermined by using non-destructivemethods.As a result of the analysis of defects and damages of the floor slab, its technical condition had been assessed as unfit for normal service –condition category "3" according to DSTU-N BB.1.2-18:2016.For the floor slab repair, recommendations for the restoration of the protective concrete cover by using a repair polymer-cement mixture have been developed. The column in axes 3b / Vb has beenreinforced with steel casing after the 8th-floor slabrepairing.The verification analysis of the floor slab stiffness, considering real concrete strength, has been worked out by the limit state method by using a computational model developed with the finiteelement method by the Lira-CAD software package.The full-scale test of the 8th-floor slab section has carried out after the repair and restoration works and the strengthening of the repair concrete.The 8th-floor slab section loading has carried outusing a pool filled with water. Load on the floorslab section has been applying by steps with a timedelay after each step. The floor slab test displacements did not exceed the limit values.