REPAIR OF PORTICO ELEMENTS AND DRAINAGE SYSTEM OF THE HUSEJNIJA MOSQUE IN GRADAČAC

In 2004, the Commission for the Preservation of National Monuments declared the "Architectural Complex of Husejnija (Husein-kapetan Gradaščević) Mosque in Gradačac" a national monument of Bosnia and Herzegovina. The mosque belongs to the type of central domed mosque with a portico covered by three small domes. In September/October 2023, cracks were observed on six arches, the capitals of two columns, and the base of one column in the portico of the mosque. Geotechnical investigative works included the creation of three excavations and two boreholes with continuous Standard Penetration Tests (SPT). The excavations reveal layers below the ground level, consisting of a well-bound sandy artificial fill from the ground surface to a depth of 1.35 meters, a layer of poorly bound artificial stony material from 1.35 to 2.45 meters, and a layer of natural clay at greater depths. It is assumed that over time, due to water seepage from the hillside and rainfall runoff from the mosque, there has been a change in the physical-mechanical properties of the foundation soil and partial settling of the portico structure. In addition to the existing channel on two sides of the mosque, a drainage ring around the building and a drainage curtain on the uphill slope have been designed. Also, underpinning of the portico foundations in alternating segments has been designed to strengthen the stone masonry layer and prevent further settling and development of cracks in the portico elements. After the works are completed, a 12-month monitoring period is planned, followed by an analysis and repair of the cracks.