Analisa Struktur Jembatan Melengo Kabupaten Siak Terhadap Hasil Uji Beban Dinamis

The Melengo Bridge is one of the bridges in Siak Regency, its existence not only as a transportation infrastructure, its shape resembling a butterfly is used as a tourism object. However, behind its grandeur also saves the uniqueness of the technique, where the placement of the bridge pinched both sides, this is not usually done. Bridge with an arch taper box steel frame structure with a span length of 75m with a main structure of 66m and a span width of 8.5m. This study is to determine the actual condition of the bridge compared to the natural bridge by dynamically loading test. The sensors used are strain gauge, accelerometer and LVDT. Testing is done by giving a load using a dump truck with a load of 15 tons that passes the bridge at speeds of 10 km / hour, 20 km / hour, 30 km / hour and 40 km / hour and without a speed trap, the position of the vehicle through the bridge in the middle of the bridge body. The maximum deflection value that occurs in dynamic loading testing occurs in scheme 4 with a truck speed of 40 km / h with a yield deflection value of LVDT of 11.37 mm. The value of dynamic magnification (DLA - dynamic load alloawance ) based on the results of testing and comparison of the data above can be concluded that on the Melengo Bridge, the maximum result is DAF = 1.35. Comparison of the actual frequency and natural frequency of the Melengo Bridge produces a frequency of 3.91 Hz, greater than the calculated bridge structure frequency of 2.17 Hz, the criteria for the bridge condition are good and there is no damage. This proves that the existing bridge structure is more rigid compared to structural modeling in software. The rating factor (diagnostic load testing) of the Melengo Bridge based on the test shows that the smallest RF value is the RF inventory rating at the moment in the cross beam element with a value of 1.17 and 1.96 at the RF operating rating. RF values> 1 indicate that the load used on daily loads is safe against the bridge with a maximum truck speed of 20 km / h. Maximum Inventory Load = 1.17 x 15 tons = 17.55 tons and maximum operating load = 1.96 x 15 tons = 29.4 tons