JPS6147241B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bed frame type track structure for saving labor on maintenance of railway tracks.

In order to improve the subsidence characteristics of conventional bedded tracks due to train loads, a paved track was developed that uses large block sleepers (LPC), which are larger than regular sleepers, and fixes the periphery and bottom of the sleepers with asphalt injection material. However, because the trackbed crushed stone is solidified, it is generally difficult to repair the area below the large block sleepers even if the track subsides.

In addition, in general slab tracks, in order to transmit the horizontal load applied to the track to the rigid roadbed below, it is necessary to create protrusions that are integrated with the lower rigid roadbed.

In order to compensate for these drawbacks, the present invention reduces the load strength by using a frame-shaped precast concrete member that has a larger supporting area than conventional large sleepers and is longer in the rail direction like a track slab. In addition to reducing track settlement, this bedded track resists horizontal loads due to the asphalt-based injection material injected into the periphery and bottom of the frame-shaped precast concrete members, which solidifies as a single piece, and the shear strength of the crushed stone. It provides structure.

Embodiments of the present invention will be specifically described below with reference to the drawings.

Figures 1a and 1b show a plan view and a cross-sectional view of a bed frame type track structure according to the present invention, in which a reinforced roadbed 5 consisting of a sand layer, a grain-sized crushed stone layer, an asphalt concrete layer, etc. is placed on an earth roadbed 6. A crushed stone layer 3 that has been properly compacted is provided on the reinforced roadbed 5, a frame-shaped precast concrete member 2 is installed at a predetermined position on the crushed stone layer 3, and the surrounding area of the frame-shaped precast concrete member 2 is The bottom part is fixed together with an asphalt-injected crushed stone layer 4, and the rail 1 is supported on the frame-shaped precast concrete member 2 via a fastening device.

If the asphalt-based injection material used here is one that solidifies over time and exhibits a predetermined strength, the horizontal load applied to the track can be resisted by the asphalt injection crushed stone layer 4.

A static load test, a wheelset drop test, a dynamic load test, and a horizontal resistance force test were conducted on the bed frame type track structure constructed according to the present invention, and the following results were obtained.

(1) In the static load test, the maximum vertical displacement of each part of the track for a wheel load of 8 tons was 0.97 to 1.38 mm for the rail and 0.31 to 0.75 for the frame-type precast concrete member.
mm, the raceway spring coefficient and track slab support spring coefficient are respectively 71.5t/cm and 11.5Kg/cm on average.
^cm3 , and has characteristics that are intermediate between existing slab-based trackways and bedded trackways.

Furthermore, for a lateral force of 6 tons, the maximum lateral displacement of each part of the track was 5.5 to 5.7 mm for the rail and 0.25 to 0.51 mm for the frame-shaped precast concrete member.

(2) In the wheel axle drop test, the drop height was 20 mm, and the average value of the orbital spring coefficient and damping coefficient as representative values at the center (middle) cross section of the frame-shaped precast concrete member was 68.7 t/cm, 125 Kg・sec/cm
It was hot.

(3) Dynamic load tests totaled 4.48 million times (5,600 times per ton)
As a result of the repeated impact test (equivalent to 10,000 tons), the maximum cumulative settlement of the track was 4.8 mm, which is about the same as that of the track tested using ordinary PC concrete sleepers.
It was 1/3 warm.

(4) In the horizontal resistance test, since the injection material is an asphalt-based material with high temperature sensitivity, the resistance is the lowest at high temperatures in summer, and the resistance force of the track bed for a displacement of 1 mm is approximately 1300 kg/m in the vertical direction and 1300 kg/m in the lateral direction. is 1600
It was about Kg/m.

As explained above, the track bed frame type track structure constructed according to the present invention has a large supporting area and a frame type track structure that is long in the rail direction, in place of the conventional sleepers laid on the track bed or large block sleepers. By using cast concrete members, the load is dispersed compared to general roadbeds and paved tracks, and the settlement characteristics of the track are improved.In order to handle horizontal loads, the cast concrete members are injected around and at the bottom of the frame-shaped precast concrete members. It is a structure that provides resistance due to the asphalt-based material, and there is no need to provide protrusions such as slab tracks.

In addition, by scattering crushed stone around the frame-shaped precast concrete member and inside the frame up to the surface of the member, it is also possible to reduce noise compared to the slab track.

[Brief explanation of the drawing]

FIGS. 1a and 1b are a plan view and a sectional view of a bed frame type track structure according to the present invention. 1...Rail, 2...Frame-shaped precast concrete member, 3...crushed stone layer, 4...asphalt injection crushed stone layer, 5...reinforced roadbed, 6...earth roadbed.

Claims (1)

[Claims] 1. In a railway track on an earth roadbed, a frame-shaped precast concrete member that supports the rail, an asphalt-injected crushed stone layer that fixes the frame-shaped precast concrete member in the horizontal direction, and a reinforced roadbed that supports the crushed stone layer. A bed frame type track structure consisting of.