Method for filling railway foundation with low-cost steel slag

Abstract

The invention discloses a method for filling a railway foundation with low-cost steel slag. The method comprises the steps that the railway foundation is constructed; the railway foundation comprises a steel rail erected on a concrete sleeper, railway ballast is arranged below the concrete sleeper, a steel slag rolling layer is arranged at the bottom of the railway ballast, and a pile is vertically arranged below the steel slag rolling layer. The components of the steel slag rolling layer comprise more than 80% of steel slag. Compared with the prior art, the problems that an existing railway foundation constructed through traditional graded broken stone is insufficient in durability and rolling resistance strength and high in cost can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of railway foundation construction, in particular to a method for replacing railway foundation filling by using low-cost steel slag instead of traditional graded crushed stone. Background Art

[0002] Existing large-scale logistics enterprises, especially steel production groups, often use internal railways for short-distance logistics transportation. This type of railway foundation includes rails on concrete sleepers, ballast under the concrete sleepers, a rolling layer of traditional graded crushed stones at the bottom of the ballast, and large stones under the rolling layer. Vertical piles are set between the large stones to support the entire foundation. Because the traditional graded crushed stones have poor internal friction and anti-freezing properties, insufficient durability and rolling resistance, and the price is constantly rising, it is necessary to find low-cost, easy-to-obtain materials with good physical and mechanical properties for railway foundation construction. Summary of the invention

[0003] The problem to be solved by the present invention is to provide a method for filling railway foundation with steel slag at a low cost, so as to solve the problems that the railway foundation constructed with conventional graded crushed stone has insufficient durability and rolling resistance and high cost.

[0004] In order to solve the above problems, the technical solution of the present invention is: the method of low-cost steel slag filling railway foundation includes constructing a railway foundation; the railway foundation includes steel rails mounted on concrete sleepers, ballast is under the concrete sleepers, a steel slag rolling layer is provided at the bottom of the ballast, and piles are vertically provided under the steel slag rolling layer; the components of the steel slag rolling layer include more than 80% steel slag.

[0005] In the above technical solution, a more specific solution may be: the steel slag rolling layer comprises the following components: 52%-59% of 10-20 mm steel slag, 22%-28% of 5-10 mm steel slag, 9-11%% of machine-made sand, and the remainder is mineral sand.

[0006] Furthermore: the steel slag rolling layer includes the following components: 55% of 10-20 mm steel slag, 25% of 5-10 mm steel slag, 10% of machine-made sand and 10% of mineral sand.

[0007] Further: the construction steps include mixing the steel slag, machine-made sand and mineral sand in a good proportion, and then backfilling the space of the steel slag compaction layer in layers, with each layer being between 20-30cm thick.

[0008] Furthermore: the construction steps also include constructing the entire road section in sections, with the length of each section controlled between 40-50m.

[0009] Due to the adoption of the above technical solution, the present invention has the following beneficial effects compared with the prior art: This low-cost steel slag filling railway foundation method uses steel slag (10-20mm in size) and steel slag powder (5-10mm in size) discarded by steel companies, and uses the excellent physical and mechanical properties of steel slag, which has good internal friction and extrusion force and good frost resistance. It can increase the effective durability and rolling resistance of the finished product, and combines machine-made sand and mineral sand to design the best steel slag mix ratio to replace the traditional graded crushed stone to fill the rolling layer of the railway foundation, so that the entire railway foundation has good physical and mechanical properties; it also solves the problem of high cost of steel production enterprises in stacking and processing steel slag. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic structural diagram of a railway foundation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0011] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings: The low-cost slag filling railway foundation method includes a railway foundation construction.

[0012] like Figure 1 The railway foundation shown includes a rail 1 mounted on a concrete sleeper 2, a ballast 3 under the concrete sleeper 2, a slag rolling layer 4 at the bottom of the ballast 3, and piles 5 vertically arranged under the slag rolling layer 4; the components of the slag rolling layer include more than 80% of slag.

[0013] In order to study the influence of different particle sizes of steel slag on grading performance and steel slag utilization, the gradation layer test section was implemented in two sections: Scheme 1 uses steel slag of two specifications, 5-10mm and 10-20mm; Scheme 2 uses 5-10mm steel slag, as shown in the gradation design table below.

[0014] The Schellenberg leakage test and the Kentburg dispersion test were carried out on Schemes 1 and 2 to verify the designed mix design. According to the designed gradation and optimal oil-stone ratio, the road performance such as high temperature stability, water stability and low temperature crack resistance were tested.

[0015] In order to test whether the volume stability of steel slag SMA can meet the requirements, the Marshall specimen was kept in a constant temperature water bath at 60℃ for 72 hours, and its volume expansion rate was measured to evaluate its stability. After testing, the water expansion rate of Scheme 1 was 0.18%, and the water expansion rate of Scheme 2 was 0.12%. Scheme 1 was finally selected as the railway roadbed replacement scheme for the No. 3 blast furnace railway supporting system project of our company.

[0016] The same tests were conducted on the gradation similar to Scheme 1, and the water expansion rate of this component range was also 0.18%, which can be used as the railway roadbed replacement scheme for other blast furnace railway supporting system projects. This component includes 52%-59% 10-20mm steel slag, 22%-28% 5-10mm steel slag, 9-11% machine-made sand, and the rest is mineral sand. There are several schemes with gradation similar to Scheme 1, including Scheme 3: 52% 10-20mm steel slag, 28% 5-10mm steel slag, 9% machine-made sand, 11% mineral sand; Scheme 4: 59% 10-20mm steel slag, 22% 5-10mm steel slag, 10% machine-made sand, and 9% mineral sand.

[0017] The construction steps include: A. Use 5-10mm, 10-20mm steel slag and steel slag powder to design the best steel slag mix ratio, and replace graded crushed stone for foundation replacement.

[0018] B. Before construction, conduct a comprehensive inspection of the underlying layer, including the cross slope, width, flatness, etc., remove gravel, loose soil, debris, etc., sprinkle water evenly to keep the surface moist without leaving any visible water.

[0019] C. After the steel slag mixture is mixed according to the mix ratio, it shall be transported to the construction site in time for backfill construction. The backfilling shall be carried out in layers, with each layer having a thickness of 20-30cm.

[0020] D. The rolling construction should be carried out in sections, following the principle of light first and heavy later, slow first and fast later. The length of each section should be controlled between 40-50m.

[0021] This method uses steel slag (10-20mm in size) and steel slag powder (5-10mm in size) discarded by steel enterprises, and utilizes the excellent physical and mechanical properties of steel slag, which has good internal friction and extrusion force and good frost resistance. It can increase the effective durability and rolling resistance of the finished product, and combines machine-made sand and mineral sand to design the best steel slag mix ratio to replace the traditional graded crushed stone to fill the rolling layer of the railway foundation, so that the entire railway foundation has good physical and mechanical properties; it also solves the problem of high cost of steel production enterprises in stacking and processing steel slag.

[0022] The method is convenient, safe and reliable in construction; it improves work efficiency and the comprehensive utilization rate of steel slag; while ensuring safety, quality and progress, it reduces construction costs and solves the environmental pollution caused by steel slag stacking.

Claims

1. A method for filling railway foundation with low-cost steel slag, characterized in that: Includes construction of a railway foundation; The railway foundation comprises steel rails mounted on concrete sleepers, ballast is under the concrete sleepers, a steel slag rolling layer is provided at the bottom of the ballast, piles are vertically provided under the steel slag rolling layer; the components of the steel slag rolling layer include more than 80% of steel slag.

2. The method for filling railway foundation with low-cost steel slag according to claim 1, characterized in that: The steel slag rolling layer includes the following components: 52%-59% of 10-20 mm steel slag, 22%-28% of 5-10 mm steel slag, 9-11% of machine-made sand, and the rest is mineral sand.

3. The method for filling railway foundation with low-cost steel slag according to claim 2, characterized in that: The steel slag rolling layer includes the following components: 55% of 10-20 mm steel slag, 25% of 5-10 mm steel slag, 10% of machine-made sand and 10% of mineral sand.

4. The method for filling railway foundation with low-cost steel slag according to claim 3, characterized in that: The construction steps include mixing steel slag, machine-made sand and mineral sand, and then backfilling the space of the steel slag compaction layer in layers, with each layer being between 20-30cm thick.

5. The method for filling railway foundation with low-cost steel slag according to claim 4, characterized in that: The construction steps also include dividing the entire road section into sections, with the length of each section controlled between 40-50m.

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