PERFORMANCE ANALYSIS OF THROUGH TRUSS BRIDGE BASED ON TECHNICAL DRAFT REQUIREMENTS FOR HEAVY TRAIN 1435 MM

• Main Author: Nuranita, Badriana
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/42227
• Institution: Institut Teknologi Bandung

A bridge is an infrastructure from the road network that plays an important role in the economic, socio-cultural, and environmental sectors. Therefore, the need to build a bridge is significantly increased along with the needs and development of an area. Steel truss bridges have been considered effective and popular in Indonesia, including the use of system for railway bridges. Among the various types of steel bridge, Warren Truss is the most common steel bridge and often used in Indonesia, as in the case of the Warren Truss bridge type WTT (Welded Through Truss) where it is available in standard drawings for design of railway bridges in Indonesia with varied spans. The existing standard drawing is intended for a railway track gauge of 1067 mm, whereas in order to meet current and future loading and traffic requirements according to applicable international standards, the Ministry of Transportation is updating the related regulations regarding railway planning in the Draft Appendix to Ministerial Regulations Transportation in 2017 for Technical Requirements of Railway Tracks for Heavy Train with a 1435 mm railway track gauge design. This study analyzed the performance of the upper structure of the typical railway bridge type WTT 42 m by comparing the design technical criteria contained in the previous regulation, namely the Minister of Transportation Regulation Attachment No. 60 of 2012 for Technical Requirements for Railroad, to the technical criteria in the latest draft regulation. The results are evaluated in terms of stress ratio values and structural deflections, with the structures and the corresponding loads modeled into: Model 1 bridges (existing structures with old regulations), Model 2 (existing structures with new regulations), and Model 3 (new structures recommended with new regulations). The analysis result indicated that the railway bridge type WTT 42 m was able to accommodate the technical requirements in the Ministerial Regulation. However, it was unable to accommodate the technical requirements contained in the Draft Annex to the Minister of Transportation Regulation in 2017 because there are significant differences between the value of the loads and railway requirements that are imposed. Therefore, a new or modified structure is required. The modification in this study is conducted by increasing the thickness of the cross-section or by completely changing the dimensions of the cross-section profile for critical elements such as stringers, floor beam, and end post. As a result, a decrease in stress ratio was obtained for floor beam in the range of 36.96-44.24%. For stringers, a decrease in stress ratio was identified in the range of 46.33-55.31%, following the changing of profile dimensions. For end posts, the stress ratio decreased around 57.47-57.78% by increasing the thickness of flange and web plates. To sum up, with the updated draft regulations that is currently in the process of completion, the existing typical WTT bridge design exists seems to be ineffective. Therefore, a new typical WTT bridge that adopts the 1435 mm railway track gauge is needed based on the latest draft regulations.