A new and old roadbed construction lap joint structure

Abstract

This utility model discloses a construction overlap structure for new and old roadbeds, including a stone powder slag layer, several embedded steps, and several geogrids. The stone powder slag layer is backfilled on the inner and outer sides of an existing retaining wall. The new roadbed is set on top of the stone powder slag layer. The several embedded steps are excavated on one side of the old roadbed and form an interlocking structure with one side of the new roadbed. Several geogrids are laid and fixedly connected to the upper ends of the embedded steps, and all geogrids are anchored into the new roadbed. In this utility model, the stone powder slag layer backfilled on the inner and outer sides of the existing retaining wall enhances the bearing capacity of the bottom foundation to ensure the stability of the new and old roadbeds at the overlap. The several embedded steps on one side of the old roadbed form an interlocking structure with one side of the new roadbed, enhancing the roadbed interlocking force. The geogrids are constructed in stages, enhancing the bonding force between the new and old roadbeds. In summary, this construction overlap structure for new and old roadbeds can improve the quality of the overlap.

Description

Technical Field

[0001] This utility model belongs to the field of new and old roadbed overlapping technology, and in particular relates to a construction overlapping structure for new and old roadbeds. Background Technology

[0002] The technology for connecting the subgrades of new and old roads is particularly important. Under normal circumstances, the settlement of the subgrade of a new road is greater than that of the old road. This can easily cause subsidence and road surface cracking, thereby greatly reducing the normal service life of the road and potentially causing traffic accidents. Utility Model Content

[0003] To overcome the shortcomings of existing technologies, this utility model provides a construction overlap structure for new and old roadbeds, which can improve the quality of the overlap between new and old roadbeds.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A joint structure for the construction of new and old roadbeds, comprising:

[0006] Stone powder slag layer, the stone powder slag layer is backfilled on the inside and outside of the existing retaining wall, and a new roadbed is set on the top of the stone powder slag layer;

[0007] Several levels of embedded steps are excavated on one side of the old roadbed and form an interlocking structure with one side of the new roadbed.

[0008] Several geogrids are laid and fixedly connected to the upper end of several embedded steps, and all geogrids are anchored into the new roadbed.

[0009] The beneficial effects of adopting the above technical solution are as follows: the backfilling of stone powder and slag layers on the inner and outer sides of the existing retaining wall enhances the bearing capacity of the bottom foundation, thereby ensuring the stability of the new and old roadbeds at the joint; several embedded steps on one side of the old roadbed form an interlocking structure with one side of the new roadbed, enhancing the interlocking force of the roadbed; the graded construction of several geogrids enhances the bonding force between the new and old roadbeds; in summary, this construction joint structure for the new and old roadbeds can improve the joint quality of the new and old roadbeds.

[0010] Furthermore, the upper end of the stone powder slag layer is flush with the upper end of the existing retaining wall.

[0011] Furthermore, the cross-section of the stone powder slag layer is trapezoidal, with the upper end of the stone powder slag layer being wider than the lower end.

[0012] Furthermore, the lower end of the stone powder slag layer is 0.5m wide, and the slope ratio on both sides of the stone powder slag layer is 2:1.

[0013] Furthermore, the stone powder slag layer includes several layers of stone powder slag backfill compacted layer, the thickness of the stone powder slag backfill compacted layer is not greater than 20cm, and the compaction degree of the stone powder slag backfill compacted layer is ≥96%.

[0014] Furthermore, the upper end of the embedded steps slopes inward to form a gradient.

[0015] The beneficial effects of adopting the above technical solution are as follows: This arrangement is designed to form an interlocking structure with one side of the new roadbed, thereby preventing the new roadbed from slipping.

[0016] Furthermore, one end of the geogrid is fixedly connected to the embedded step, and the other end of the geogrid is provided with a reverse fold.

[0017] Furthermore, the other ends of all geogrids are flush.

[0018] Furthermore, the geogrid is a biaxial tensile geogrid.

[0019] Furthermore, one end of the geogrid is fixed to the embedded step by several U-shaped steel nails.

[0020] The beneficial effects of this utility model are as follows:

[0021] The backfilling of stone powder and slag layers on both the inner and outer sides of the existing retaining wall enhances the bearing capacity of the bottom foundation, ensuring the stability of the new and old roadbeds at the joint. Several embedded steps on one side of the old roadbed form an interlocking structure with one side of the new roadbed, enhancing the interlocking force of the roadbeds. Several geogrids are constructed in stages, enhancing the bonding force between the new and old roadbeds. In summary, this joint structure for the construction of new and old roadbeds can improve the quality of the joint between the new and old roadbeds. Attached Figure Description

[0022] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings. Wherein:

[0023] Figure 1 A schematic diagram of the structure of one embodiment of the present invention is shown;

[0024] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.

[0025] Figure label:

[0026] 1. Existing retaining wall; 2. Stone powder slag layer; 3. New roadbed; 4. Geogrid; 401. Reverse fold section; 5. Embedded steps; 6. Old roadbed. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings.

[0028] This utility model provides a new and old roadbed construction overlap structure, such as Figure 1 As shown, it includes:

[0029] Stone powder slag layer 2 is backfilled on the inner and outer sides of the existing retaining wall 1, and a new roadbed 3 is set at the top of the stone powder slag layer 2.

[0030] Several levels of embedded steps 5 are excavated on one side of the old roadbed 6 and form an interlocking structure with one side of the new roadbed 3.

[0031] Several geogrids 4 are laid and fixedly connected to the upper end of several embedded steps 5, and all geogrids 4 are anchored into the new roadbed 3.

[0032] Among them, three sections of the new roadbed can be filled and compacted with plain soil in layers.

[0033] Understandably, the backfill of stone powder and slag layers 2 on the inner and outer sides of the existing retaining wall 1 enhances the bearing capacity of the bottom foundation to ensure the stability of the new roadbed 3 and the old roadbed 6 at the joint; several embedded steps 5 on one side of the old roadbed 6 form an interlocking structure with one side of the new roadbed 3, enhancing the interlocking force of the roadbed; several geogrids 4 are constructed in stages, enhancing the bonding force between the new and old roadbeds and achieving the expected construction effect; in summary, this new and old roadbed construction joint structure can improve the joint quality and stability of the new and old roadbeds.

[0034] In one embodiment, the upper end of the stone powder slag layer 2 is flush with the upper end of the existing retaining wall 1.

[0035] In one embodiment, the cross-section of the stone powder slag layer 2 is trapezoidal, and the upper end of the stone powder slag layer 2 is wider than the lower end of the stone powder slag layer 2.

[0036] In one embodiment, the lower width of the stone powder slag layer 2 is 0.5m, and the slope ratio of both sides of the stone powder slag layer 2 is 2:1; the stone powder slag layer 2 includes several layers of stone powder slag backfill compaction layer, the thickness of the stone powder slag backfill compaction layer is not greater than 20cm, and the compaction degree of the stone powder slag backfill compaction layer is ≥96%.

[0037] It should be noted that the overlap between the new and old roadbeds is located above the existing retaining wall 1. To prevent uneven settlement from affecting the overlap of the new and old roadbeds after backfilling on the inside and outside of the retaining wall, and because the existing backfilling is limited and large machinery cannot be used for compaction, a layered stone powder slag backfilling technique is adopted to replace the traditional plain soil backfilling, so as to form several layers of stone powder slag backfill compaction layers, and finally form stone powder slag layer 2 on the inside and outside of the existing retaining wall 1. In addition, each layer of stone powder slag backfill compaction layer can be compacted using small tamping machinery.

[0038] In one embodiment, the upper end of the embedded step 5 is inclined inward to form a 4% slope so as to form an interlocking structure with one side of the new roadbed 3, thereby preventing the new roadbed 3 from slipping.

[0039] It should be noted that before constructing the embedded steps 5, the surface of the old roadbed 6 will be cleaned to a thickness of 30cm, and then the embedded steps 5 with a width of 1m and a height of 0.6m will be excavated.

[0040] In one embodiment, one end of the geogrid 4 is fixedly connected to the embedded step 5, and the other end of the geogrid 4 is provided with a folded portion 401, specifically folded back 50cm at the other end of the geogrid 4.

[0041] In one embodiment, the other ends of all geogrids 4 are flush.

[0042] It should be noted that a 2.5m wide geogrid 4 is laid on the first level of embedded step 5. Since the width of each level of embedded step 5 is 1m, the geogrid 4 on each subsequent level of embedded step 5 will be 1m wider to ensure that the other ends of all geogrid 4 are flush.

[0043] In one embodiment, the geogrid 4 is a GSL50 biaxial tensile geogrid, whose longitudinal and transverse ultimate tensile strength should not be less than 50KN / m, and whose elongation at nominal tensile strength should not be greater than 12%.

[0044] In one embodiment, one end of the geogrid 4 is fixed to the embedded step 5 by a number of U-shaped steel nails; wherein, the U-shaped steel nails are made of steel bars with a diameter of 8mm, and the number of U-shaped steel nails are evenly distributed along the length direction of the embedded step 5, and the spacing between two adjacent U-shaped steel nails is 2m; in addition, the open end of the U-shaped steel nail passes through the geogrid 4 and is inserted into the embedded step 5 so that one end of the geogrid 4 is fixed to the old roadbed 6.

[0045] In summary, this utility model adopts an embedded step 5 and a bidirectional geogrid 4 for the overlapping position of the new and old roadbeds at the top of the existing retaining wall 1. Compared with the traditional construction method for overlapping new and old roadbeds, it has higher construction efficiency, simpler operation, and better overlapping quality, and has high promotion and application value.

[0046] In the description of this utility model, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0047] While specific embodiments of the present invention have been described herein with reference to them, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A joint structure for the construction of new and old roadbeds, characterized in that, include: Stone powder slag layer (2), the stone powder slag layer (2) is backfilled on the inner and outer sides of the existing retaining wall (1), and a new roadbed (3) is set at the upper end of the stone powder slag layer (2). Several levels of embedded steps (5), the several levels of embedded steps (5) are excavated on one side of the old roadbed (6) and form an interlocking structure with one side of the new roadbed (3); Several geogrids (4) are laid and fixedly connected to the upper end of several embedded steps (5), and all the geogrids (4) are anchored into the new roadbed (3).

2. The overlapping structure for new and old roadbed construction according to claim 1, characterized in that, The upper end of the stone powder slag layer (2) is flush with the upper end of the existing retaining wall (1).

3. A new and old roadbed construction overlap structure according to claim 1 or 2, characterized in that, The cross-section of the stone powder slag layer (2) is trapezoidal, and the upper end of the stone powder slag layer (2) is wider than the lower end of the stone powder slag layer (2).

4. The overlapping structure for new and old roadbed construction according to claim 3, characterized in that, The lower end of the stone powder slag layer (2) has a width of 0.5m, and the slope ratio of both sides of the stone powder slag layer (2) is 2:

1.

5. A new and old roadbed construction overlap structure according to claim 1 or 2, characterized in that, The stone powder slag layer (2) includes several layers of stone powder slag backfill compaction layer, the thickness of the stone powder slag backfill compaction layer is not greater than 20cm, and the compaction degree of the stone powder slag backfill compaction layer is ≥96%.

6. The overlapping structure for new and old roadbed construction according to claim 1, characterized in that, The upper end of the embedded step (5) slopes inward to form a gradient.

7. The overlapping structure for construction of new and old roadbeds according to claim 1, characterized in that, One end of the geogrid (4) is fixedly connected to the embedded step (5), and the other end of the geogrid (4) is provided with a folded part (401).

8. The overlapping structure for construction of new and old roadbeds according to claim 7, characterized in that, The other end of all the geogrids (4) is flush.

9. A new and old roadbed construction overlap structure according to any one of claims 1 or 7, characterized in that, The geogrid (4) is a biaxial tensile geogrid.

10. A new and old roadbed construction overlap structure according to claim 1 or 7, characterized in that, One end of the geogrid (4) is fixed to the embedded step (5) by several U-shaped steel nails.

Images