The "Strengthening Agricultural Accessibility and Downstream Processing Through the Implementation of Modular Bamboo Bridges in Purwosari Village"

Abstract

The structural analysis of a modular bamboo bridge based on a Cremona truss configuration intended to improve rural connectivity for agricultural value-chain activities in Wonogiri Regency, Indonesia. The analysis is based on the submitted research proposal and the provided side- and top-view drawings. The main geometry consists of a 13 m overall bridge length, 10 m deck length, 1.8 m deck width, 8 m truss span, and approximately 2 m maximum truss height. A two-dimensional truss idealization was developed using nine lower nodes, nine upper nodes, vertical members, and diagonal members. An initial service scenario of 5 kPa live load and 0.5 kPa preliminary deck/dead-load allowance was adopted as an explicit numerical assumption. The Cremona analysis produced support reactions of 19.80 kN at each support, an equivalent global bending moment of 39.60 kNm per truss plane, a maximum lower-chord tensile force of 19.80 kN, a maximum upper-chord compressive force of 19.56 kN, and a maximum diagonal compressive force of 22.91 kN. An elastic frame-stiffness verification produced a maximum vertical deflection of approximately 10.64 mm and a maximum local member bending moment of approximately 0.313 kNm. The results indicate that the truss configuration efficiently transforms global bending into axial forces; however, connection capacity, bamboo variability, actual deck loading, and static load testing remain essential before operational use.

Keywords: bamboo bridge; cremona truss; structural analysis; deflection; bending moment; wonogiri.