![]() ![]() For the third model, beams and mullions both had a 40 mm circular section and a 2 mm thickness. The second model was made with beams with a circular section of 40 mm and a thickness of 1.5 mm and uprights with a square section of 35 mm and a thickness of 1.5 mm. The first model contained beams with a circular section 25 mm in diameter and 1.5 mm thick and mullions with a circular section of 40 mm in diameter and 1.5 mm in thickness. Initially, three different configurations of steel railings were analyzed analytically and experimentally. Other studies tested steel wooden structures and high-density polyethylene, and the results showed that in some cases, the limit displacement values defined in standard EN 13374 were exceeded. Lan and Daigle carried out experimental, static, and dynamic tests, according to the Quebec Code S-2.1, r.4, to validate the use of the metallic support of the slab as a support for 38 mm × 89 mm wooden crossings, concluding that these guardrail structures are safe and comply with the code. After the tests, the authors proceeded to take the structures to rupture, surpassing the OSHA load criterion of 900 N and reaching a load of 3600 N. Both wooden guardrail systems met these requirements. experimentally evaluated two commercial wooden guardrail systems to verify compliance with the OSHA load requirement, of a 50 mm × 100 mm cross-section with an impact load between 900 N and 1720 N and an estimated impact velocity of 1.52 m/s. Static and impact tests conducted on wooden structures with a 38 mm × 89 mm profile and poles spaced at 1.80 m under the requirements of the Québec Safety Code for the Construction Industry (S-2.1, r.6) demonstrated that the structures do not always meet the requirements. Therefore, a better understanding and analysis of how forces operate in these systems is necessary to design systems that ensure the necessary protection of the people involved in the construction process. The system becomes complex in terms of evaluating safety owing to the dynamic phenomena that occur. There are many differences when applying the mechanical strength and tolerance requirements, particularly in the simulation of the impact of workers on guard rail structures. The guardrail system is the most widely adopted edge protection method, and some configurations provide a better feeling of protection for workers than others. They represent one of the leading causes of bans and prohibitions by the inspections of the Brazilian Ministry of Labor. Moreover, studies have shown that implementation of edge protection measures is not readily observed by companies, mainly because of the poor techniques used in the construction of the protection. In Brazil, the standards available for guidance regarding work at height have descriptive technical specifications on how to work at height, but contain several gaps regarding standardized methodologies for safety performance in equipment and installations. These standards show divergence in some aspects. The performance and resistance requirements for the protective structures are specified by OSHA 1926.502 in the United States of America, EN 13374 in the European Union, S-2.1, r.4 in Canada, AS/NZS 4994 in Australia and New Zealand, and in Brazil by NR 18, NR 35, and RTP 01. In the USA, OSHA 1926.502 determines that protective measures must be adopted when the work is carried out at the height of greater than 1.80 m, in Brazil, the NR 35 specifies 2.00 m, and in Canada, the code S-2.1, r.4 specifies a height of 3.00 m or 1.20 m when equipment or vehicles are being used. Guardrail structures are used worldwide as a protective measure against falls. found that in 98% of the cases analyzed, the fall was caused by a lack of protective measures. Statistics from the US Bureau of Labor Statistics show that fatal accidents due to falls from height are still the most significant cause of construction fatalities. Civil construction is one of the economic sectors with the highest number of occupational accidents. ![]()
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