Analysis of Mobile Crane and Crawler Crane Lift Capacity In Steel Box Girder Type Bridge Construction

Abstract

Purpose: The causes of work accidents in the erection process are overloading of crane capacity, operational errors, equipment conditions, and planning problems. Operation of a crane that is not in accordance with its capacity has a high chance of causing work accidents. The purpose of this study is to analyze the lifting load, determining the type and capacity of a safe crane, and the bearing capacity of the soil in the crane pad area as an optimization of the box girder steel erection process to improve work safety.

Methods/Design: This research method uses a quantitative descriptive approach. Primary data collection is based on surveys. Secondary data is obtained from testing, project documents, and literature. The independent variables of this study are lifting load, lifting angle, and crane radius.

Findings: In the calculation, the crane lifting load is 126.12 tons divided into 2 tandems so that the load is 63.1 tons. From the analysis of the 250T crane, it is known that the length of the crane boom is 24.4 meters and the working radius is 12 meters with an angle of 65 °, so the lifting capacity of the 250 T crane is 90 tons, with a load capacity rating of 73% and a safety factor of 1.4. While the analysis of the 360T crane, the length of the crane boom is 31 meters and the working radius is 12 meters with an angle of 60 °, so the lifting capacity of the 360T crane is 87 tons, with a load capacity rating of 75% with a safety factor of 1.3. Thus, it has exceeded the ASME 30.5 safety factor standard of at least 1.3.

Practical implication: With the existence of mature calculations related to lifting study cranes, it is hoped that work safety and the success of bridge erection can be improved and construction activities can run efficiently and effectively.