Charkhal is a historical building of Nepal, built of clay brick in mud mortar dated more than 105 years of age. This paper focuses on seismic vulnerability assessment and retrofit option of historic buildings charkha Adda carried by NSET just few years before the Gorkha Earthquake, which got damage during the recent Gorkha earthquake 2015. The building is a courtyard type; with a large number of openings in their facade. The building is three stories with a total height of 10.88m and largest dimension in the plan of 55.01m. The thickness of walls varies in the range of 0.8m to 0.35m with the greatest values attained at the ground floor. The building floors are thick with jack arch and steel I-sections. The foundation of the building is in strip footing. The plinth level is considerably high above the ground level with a provision for ventilation. A complete geometric and structural survey of the whole building was performed during the assessment of building. The need for safety of the building lying at high seismic zone in Nepal, the Seismic Vulnerability Assessment out was carried out to improve the building response in future earthquakes. The seismic vulnerability of the building was assessed after the following:(a) historical investigation about the building, (b) detailed geometrical investigation, (c) identification of materials by means of surveys and literature indications, (d) Detailed Intrusive Tests, (f) Detail linear static analysis of the building by means of a Finite Element (FE) model. After these steps, the FE model was used to assess the safety level of the building by means of linear static analyses, and identifying a proper retrofitting strategy for this building.

Keywords : Historical Building; Seismic Vulnerability; FE Modeling; Intrusive Test, Retrofit Option.