Rapid grout for railroad bridge bearing

Abstract

The invention provides a quick grouting material used in railroad bridge supports. The grouting material comprises the following components with parts by weight: 25-60 parts of cement, 50-80 parts of sand, 2-6 parts of an expanding agent, 0.25-2.5 parts of a water reducing agent, 0.1-1.5 parts of a coagulant and 0.1-1.5 parts of a retarder. The beneficial effects of the invention are that (1) two-hour compressive strength of the grouting material used in the railroad supports is improved to more than 20MPa, the construction efficiency of a hanging bridge machine is greatly improved; (2) by virtue of a combination use of the retarder and the coagulant, the grouting material has workable performance with the fluidity being more than 240mm in 30 minutes after being blended and early-strength performance with the two-hour compressive strength being more than 20Mpa; (3) the grouting material can be used for hanging bridge construction under the conditions of low temperature and negative temperature; and (4) the volume of the grouting material swells slightly in the hardening process, which ensures that the grouted space is tightly filled.

Description

Technical field [0001] The invention relates to a special engineering material, in particular to a cement-based fast-hardening grouting material that can be used for grouting a railway bridge support. Background technique [0002] With the continuous development of my country's national economy, the railway construction mileage is also getting longer and longer. According to the "Medium and Long-term Railway Network Planning", by 2020, China's railway passenger transport capacity will be unprecedentedly increased, and rapid passenger transport between provincial capitals and large and medium cities will be built Through the passage, inter-city rapid passenger transport systems in the Bohai Rim, Yangtze River Delta, and Pearl River Delta regions will be built, and passenger dedicated lines of more than 12,000 kilometers will be built. In the construction of the railway passenger dedicated line, a large number of prefabricated box girders are hoisted. After the box girder is in plac...

AI Technical Summary

Problems solved by technology

However, existing domestic grouting materials have disadvantages such as poor fluidity, short construction time, and slow strength development. For example, the fast-hardening expansion grouting material for emergency repair construction proposed in the Chinese patent CN1356285A, the compressive strength can only reach 20MPa in 6 hours, and the initial fluidity is 250mm. None of them can meet the requirements of grouting at the joints of box girders and railway bridge supports