Subway ballast bed concrete replacing process in special limiting condition

Abstract

The invention discloses a subway ballast bed concrete replacing process in a special limiting condition. The subway ballast bed concrete replacing process comprises the following steps of arranging ofcurtain water stopping; arranging of safety facilities; pulling support of a track; connecting-point type static force concrete dividing; static force concrete dismantling; dismantling and assemblingof sleepers; track supporting; manual water clearing, rebar supplementing and planting; deep water stop treatment; construction interface treatment; track measuring and fine tuning; formwork supporting, concrete pouring; and track geometrical state monitoring. The subway ballast bed concrete replacing process adopts a blocking dismantling and replacing method on ballast bed concrete, and train derailing due to long-time and large-span hanging in the air of a steel rail is avoided; a concrete new and old interface is subjected to treatment by adopting a high-density cement-permeable crystalline material, and weak points of construction seams are effectively overcome; the method of connecting-point type static force cutting and static force dismantling is adopted to conduct concrete dismantling, influence on the periphery of a dismantled area is reduced, disturbance to surrounding concrete is avoided, and damage to load-bearing rebars in a structure is avoided.

Description

technical field [0001] The invention belongs to a concrete replacement process, and in particular relates to a concrete replacement process for a railway track bed in a special restricted condition. Background technique [0002] The trackless bed used in the subway is a reinforced concrete structure. Due to long-term erosion by external water, changes in the properties of alkaline substances, and rolling vibrations, the initial function of the concrete structure continues to decay, and the concrete components will gradually segregate and overflow, and the structure will crack. Fault spalling, deformation and subsidence, disintegration tendencies and other phenomena, and with the passage of time, the geometric dimensions of the track can no longer maintain the original state, which seriously threatens the operation safety of subway trains. [0003] When the concrete of the ballast bed is damaged, it will affect the safe operation of the subway, and the concrete of the ballast...

AI Technical Summary

Problems solved by technology

[0004] However, replacing and repairing the track bed under the condition of non-stop subway operation faces many insurmountable problems, such as: (1) There is no precedent for reference in China, and the existing urban subway operating companies do not have the same case and feasible plan; (2) Relevant experts could not come up with a standardized and feasible maintenance plan; (3) Concrete building specifications, ordinary concrete can only meet the design load-bearing requirements after 28 days of pouring, and the concrete will disintegrate under external force or vibration during the curing period. The daily rest time of the subway is 5 hours, 4 hours for maintenance work during the period, and only 3.5 hours for concrete pouring and curing (strength reaches C30); (4) The damaged ballast concrete cannot be removed in a large area at one time, otherwise there will be no firm foundation for restraining the rails and fixing small sleepers. Therefore, it cannot be operated; (5) The demolition of the concrete of the ballast bed cannot cause disturbance to the surrounding concrete and internal steel bars, otherwise the rep

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