DETECTION OF VERTICAL DEFORMATIONS OF A LARGE BUILDING

Abstract

The great central building of Technical University of Budapest was built during the years 1902 - 1909 mostly over the filled river bed of the Danube. The building has suffered heavy vertical deformation since then. Hence it became necessary to detect the exact amount and time course of deformation by an investigational survey. Firstly the uneven subsidences of loaded outer walls, which were resulted up to the present, were detected such, that the height of one rim passing completely around, - and was planned originally to be horizontal - was measured. Its deviations from horizontal plane practically equal to the uneven subsidences of outer walls (Figs. 1 and 2). We gained data for the uneven subsidences of the inner parts of building by analyzing previous repeated levellings taken to the axes of inner passages (Fig. 3). The overall subsidence of building was detected by using such results of levelling of first-order benchmarks placed previously in the basement of building, which were connected time by time with outer first-order benchmarks that can be taken as motionless (Fig. 5 and Tables). We have located critical sites of deformation and ascertained that the subsidence and uneven subsidence of the building is going on at present as well.Some new first-order benchmarks were established along the loaded outer walls and inside the building. Hence accurate data can be gained in the future for short periods of time (e.g. one year) for the relative and absolute movements of the building.