The Audit and Assessment of Building Structural Strength (Case Study of Mataram Islamic State University Rectorate Building)

Rectorate building of Mataram Islamic State University was designed of four story building and started
under construction on 2008. However, the construction was aborted due to lack of administration
management and left the building under incomplete condition with only foundation and the first floor
erected. Ten years afterward, the management decided to continue construct the building. This study
aimed to investigate the condition of existing building whether can be rebuilt properly corresponding to
the previous design. The investigation included structural cracks that happened on structural element as
well as the deflection of structural beams. The conditions of existing structural column have also been
investigated.
The assessment process was conducted both on field and laboratory testing. The field testing was run with
Schmidt Rebound Hammer test to know the compressive strength of structural concrete and its quality.
The waterpass, theodolite, and tape measurement were used to measure the building geometric. SAP
2000 computer package was used to analyze the structure. Loading test was carried out base on the total
measurement test which was required in SNI 03-2847-2002. The total measurement load of 700 kg/m2
was employed representing U = 85% (1,4D + 1,7L), where D was dead load and L was live load. In this
study, the loading test was conducted on 300/700 and 200/500 size beams.
Test result indicated that the qualities and the concrete compressive strengths on the building
construction elements were varied. Steel reinforcement of structural columns was good enough to
withstand the load, but, the column concrete strength should be improved. On the beam of 300/700 in the
first floor, the deflection did not exceed the maximum deflection based on the code. However, the
maximum deflection on 200/500 beam was 6.92 mm > 5.85 mm (maximum allowable deflection) and
permanent deflection after loading of 2.31 mm > 1.46 mm (maximum allowable permanent deflection).
Therefore, rehabilitation and retrofitting of structural columns and 200/500 mm beam are essential.