Technical inspection of technical underground floor elements of administrative building in lutsk

Abstract

The technical inspection results for the administrative building’s technical underground elements in city of Lutsk by the science-research construction laboratory of Lutsk National Technical University are given. The building type is a skeleton frame. In the structural scheme, metal I-beams and channel beams were used as the technical underground floor joists.

     The survey found that building elements were in operation for a prolonged period of time (up to thirty years) in absence of proper ventilation, excessive moisture due to damaged utility lines and flooding of the technical underground floor. This led to corrosion of metal elements, corrosion of reinforcing steel in precast reinforced concrete elements with insufficient concrete cover, uneven subsidence of the concrete floor.

     During the metal floor beams’ inspection, ultrasonic test of load-bearing capacity reduction for load-bearing elements due to corrosion losses was performed using an ultrasonic flaw detector. 6 samples were studied. The test results indicated that the steel beams have a general uniform surface corrosion, but the thickness of the beams’ walls and shelves meets the requirements of DSTU 8807: 2018.

     For further safe operation of the building it is recommended: to arrange for ventilation of the technical underground floor, update the utility lines  with changes and additions to the project; restore corrosion protection of metal beams; perform plastering of reinforced concrete floor slabs where concrete cover is cracked and reinforcing steel is exposed; perform restoration of the technical underground concrete floor with arrangement of slopes, an emergency drainage pit, add necessary changes and additions to the project.

     Precast reinforced concrete column series 1.020-1 / 83 which was installed instead of a metal beam, located in grid lines 29-31/G, was designed as a bending element. Calculation of the beams’load-bearing capacity showed that the strength per normal cross-sections on the applied loads was provided.