PLANNING AND TESTING OF A BALSA WOOD TRUSS BRIDGE USING THE VARIABLE OF TRUSS WEIGHT AGAINST MAXIMUM LOAD WEIGHT

Abstract

The use of lightweight materials like balsa wood in prototype bridge construction has become a fascinating topic in civil engineering, especially in laboratory-scale experimental studies. This research aims to evaluate the structural performance of a prototype balsa wood truss bridge under concentrated loading. The bridge is designed with a symmetrical truss system and a main joint at the central connection, which acts as the center for force distribution. The design process was conducted using a numerical approach through structural software to analyze the axial force and bending moment under various load scenarios, namely 10 kg, 20 kg, and 30 kg. The analysis results show that the compressive and tensile axial forces, as well as the bending moments that occur, are still within safe limits based on the specifications of balsa wood's modulus of elasticity and strength. Additionally, experimental testing was also carried out on this balsa bridge prototype. Structurally, this bridge has a total weight of 25,91 grams. The test results show that the bridge can withstand a load of 30.90 kg. When compared to the weight of its structure, the bridge demonstrates good material efficiency as it can support 1,161.327 times its own weight.