Support method and structure for shallow trench excavation and protection

Abstract

The present invention discloses a novel support method and structure for shallow trenches that can be protected as they are excavated. A channel steel or H-shaped steel with a circular notch on the top is statically pressed into the soil layer as a vertical rib support, and then a steel plate is placed behind the two vertical ribs. As the excavation is carried out, the steel plate is gradually pressed to the designed elevation by an excavator, thereby achieving the effect of protecting as the trench is excavated. The present invention has a simple process and is convenient and safe to operate.

Description

Technical Field

[0001] The present invention relates to the technical field of trench construction, and in particular to a supporting method and structure for excavating and protecting shallow trenches. Background Art

[0002] Trench construction can be seen everywhere in engineering construction. Safety accidents in trench construction have always occurred frequently, mainly manifested in personal injuries caused by trench soil collapse. The fundamental cause of trench soil collapse is improper support measures.

[0003] Generally speaking, necessary support measures are required when excavation reaches a certain depth. When excavation depths exceed 3 meters and slope reduction is not possible, steel sheet pile support is required. Existing steel sheet pile support technology is mature, and in the early stages, the steel sheet piles are embedded entirely in the trench to be excavated. The steel sheet piles are embedded in the soil, with the two pile sheets interlocking. Combined with the surrounding purlin system, they effectively constrain the trench soil and act as a water barrier. This process is mature and reliable, but the steel sheet piles are burdensome, the project cost is high, and economical.

[0004] In engineering practice, excavation depths less than 3 meters are often encountered, and slope excavation is not feasible. Since excavation depths less than 3 meters do not qualify as hazardous projects, expensive steel sheet pile structures are rarely used, and this condition has received insufficient attention. Other support methods besides steel sheet piles include channel steel support. Current channel steel support methods utilize multiple welded channel steels (i.e., multiple channel steels welded together to form a steel channel plate), which is then inserted into the trench to be excavated before excavation. However, this channel steel support method is inefficient and expensive. Existing technologies also include retaining plate support and conventional horizontal plate support methods. However, both of these support methods require the trench to be excavated to a certain depth before installation. This means that excavation precedes support, which impacts construction safety. Furthermore, assembly of the retaining plate and horizontal plate is complex and inefficient. Summary of the Invention

[0005] The purpose of the present invention is to provide a shallow trench supporting method and structure for digging and protecting at the same time, so as to overcome the shortcomings of the prior art.

[0006] To achieve the above object, the present invention provides the following technical solution: a shallow trench support method for digging and protecting at the same time, comprising the following steps:

[0007] Step 1: Use ordinary channel steel or H-shaped steel as vertical ribs and steel plates as steel retaining walls;

[0008] Step 2: Use a machine to statically press the vertical ribs into the soil layer; that is, the vertical ribs are pre-pressed into the contour line of the trench to be excavated in advance by the machine, and the vertical ribs of the contour line of the trench to be excavated on the same side are evenly spaced, and the vertical ribs of the contour line of the trench on both sides correspond to each other;

[0009] Step 3: Place the steel retaining plate in place along the soil side of the adjacent vertical ribs of the trench to be excavated on the same side, and clamp the steel retaining plate through the adjacent vertical ribs. The two adjacent vertical ribs and the corresponding steel retaining plate constitute a basic combination of the support system; multiple basic combinations are formed according to this process;

[0010] Step 4: Mechanically excavate the trench to be excavated. During the downward excavation process, the steel retaining plates at the corresponding positions are statically pressed downward to provide support.

[0011] Step 5: When the machine excavates to the specified depth, the purlins will be installed between the corresponding vertical ribs, and the steel retaining plate will be statically pressed down to the specified depth. Then, manual excavation of the trench will be carried out until the design elevation is reached.

[0012] Step 6: After the construction is completed, pull the vertical ribs and steel plates out of the soil layer and proceed to the next construction.

[0013] As a further solution of the present invention: circular holes are evenly provided on the upper part of the vertical ribs and the upper part of the steel retaining plate. When the soil layer is pulled out in the later stage, the vertical ribs and the steel plate are pulled out mechanically by passing the steel wire rope through the corresponding circular holes on the vertical ribs and the steel retaining plate.

[0014] As a further solution of the present invention: after the vertical ribs are pre-compressed, the part of the vertical rib exposed to the ground accounts for 1 / 3-1 / 4 of the length of the entire vertical rib. Through this design, during the initial excavation, the steel retaining plate can be attached to the exposed part of the vertical rib to prevent the steel retaining plate from tipping over.

[0015] As a further solution of the present invention: in step three, the two steel retaining plates on the adjacent foundation assemblies on the same side are staggered with each other.

[0016] A support for shallow trenches that is dug and protected as they are excavated, comprising vertical ribs located on both sides of the outline of the trench to be excavated, wherein the vertical ribs are partially embedded in the soil at the trench to be excavated, and is characterized in that steel retaining plates are placed on the backs of adjacent vertical ribs located on the same side of the trench to be excavated, and the steel retaining plates are clamped by adjacent vertical ribs, wherein two adjacent vertical ribs and corresponding steel retaining plates constitute a basic combination of a support system, wherein the two steel retaining plates on the adjacent basic combinations located on the same side are staggered with each other; by achieving staggered coordination of the two adjacent steel retaining plates, when there may be excessive landslide external force at a certain point in the trench, the retaining plates can be staggered to tighten the landslide external force, so that the landslide external force can be evenly distributed on each vertical rib, thereby avoiding the landslide external force from concentrating on the corresponding vertical ribs.

[0017] As a further solution of the present invention: the vertical ribs of the contour line of the trench to be excavated on the same side are distributed at equal intervals, and the positions of the vertical ribs on the contour lines on both sides of the trench to be excavated correspond to each other.

[0018] As a further solution of the present invention: circular holes are provided on the upper part of the vertical ribs and the steel retaining plate; by evenly providing circular holes on the upper part of the vertical ribs and the upper part of the steel retaining plate, when pulling out the soil layer in the later stage, the vertical ribs and the steel plate can be pulled out mechanically by passing the steel wire rope through the corresponding circular holes in the vertical ribs and the steel retaining plate.

[0019] As a further solution of the present invention: a purlin structure is arranged between the two relatively positioned basic assemblies; the purlin structure includes a rigid corbel located on the vertical ribs, two braces and two transverse braces; the two transverse braces span and are fixed on the two rigid corbels on the same purlin structure, and the two transverse braces are located between the two purlin structures, and the two ends of the transverse braces are welded and fixed to the corresponding brace positions.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The existing retaining plate or horizontal plate support is generally composed of more than three components to form a support unit. Generally, the support device can only be installed after the trench is excavated. The efficiency is not high and there are certain safety hazards when only excavation is carried out in the early stage without trying support. The present invention is to reduce the support components while ensuring the support effect, so as to achieve support as the excavation progresses, thereby improving efficiency and safety.

[0022] 2. The machines and materials used in the present invention are commonly used on construction sites, are easy to obtain, highly reliable, reusable, and economical.

[0023] 3. The present invention proposes a support structure and method with a trench depth of less than 3 meters, which has high reliability and makes up for the treatment plan for non-dangerous projects in trench construction.

[0024] 4. The present invention has been verified for reliability and can maintain a stable support effect even under extreme working conditions; under good working conditions, the surrounding purlins can be simplified or eliminated, resulting in higher operating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the installation of the vertical ribs of the present invention;

[0026] Figure 2 Schematic diagram of the installation of the steel retaining plate of the present invention;

[0027] Figure 3 A top view of the basic combined structure of the support system of the present invention;

[0028] Figure 4 for Figure 3 AA cross-sectional view.

[0029] In the figure: 1. Vertical rib; 2. Bracing; 3. Horizontal bracing; 4. Steel retaining plate; 5. Steel corbel; 6. Round hole; 7. Contour line. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] For example, see Figure 1-4 This embodiment provides a shallow trench support method for digging and protecting simultaneously, comprising the following steps:

[0032] Step 1: Ordinary channel steel or H-shaped steel is used as the vertical ribs, and steel plates are used as steel retaining boards. Circular holes are evenly arranged on the upper part of the vertical ribs and the upper part of the steel retaining board. When the soil layer is pulled out in the later stage, the vertical ribs and the steel plates are pulled out mechanically by passing the steel wire rope through the corresponding circular holes in the vertical ribs and the steel retaining board;

[0033] Step 2: Use a machine to statically press the vertical ribs into the soil layer; that is, the vertical ribs are pre-pressed into the contour line of the trench to be excavated in advance by the machine, and the vertical ribs of the contour line of the trench to be excavated on the same side are evenly spaced, and the vertical ribs of the contour line of the trench on both sides correspond to each other;

[0034] Step 3: Place the steel retaining plate in place along the soil-side of adjacent vertical ribs of the trench to be excavated on the same side, and clamp the steel retaining plate through the adjacent vertical ribs. After the vertical ribs are pre-compressed, the exposed portion of the vertical ribs on the ground accounts for 1 / 3-1 / 4 of the entire vertical rib length. This design allows the steel retaining plate to be attached to the exposed portion of the vertical ribs during initial excavation to prevent it from tipping over. The two adjacent vertical ribs and the corresponding steel retaining plates constitute a basic combination of a support system. Multiple basic combinations are formed according to this process, in which the two steel retaining plates on adjacent basic combinations on the same side are staggered with each other.

[0035] Step 4: Mechanically excavate the trench to be excavated. During the downward excavation process, the steel retaining plates at the corresponding positions are statically pressed downward to provide support.

[0036] Step 5: When the machine excavates to the specified depth, the purlins will be installed between the corresponding vertical ribs, and the steel retaining plate will be statically pressed down to the specified depth. Then, manual excavation of the trench will be carried out until the design elevation is reached.

[0037] Step 6: After the construction is completed, pull the vertical ribs and steel plates out of the soil layer and proceed to the next construction.

[0038] A shallow trench support formed by the above method that is dug and protected at the same time includes vertical ribs 1 located on both sides of the contour line 7 of the trench to be excavated, and the vertical ribs 1 are partially embedded in the soil at the trench to be excavated. It is characterized in that: steel retaining plates 4 are placed on the back sides of adjacent vertical ribs 1 located on the same side of the trench to be excavated, and the steel retaining plates 4 are clamped by adjacent vertical ribs 1, wherein two adjacent vertical ribs 1 and corresponding steel retaining plates constitute a basic combination of a support system, wherein the two steel retaining plates 4 on the adjacent basic combinations located on the same side are staggered with each other; by achieving staggered coordination of two adjacent steel retaining plates, when there may be excessive landslide external force at a certain point in the trench, the retaining plates can be staggered to tighten the landslide external force so that the landslide external force can be evenly distributed on each vertical rib 1, thereby avoiding the landslide external force from concentrating on the corresponding vertical rib 1.

[0039] The vertical ribs 1 on the contour line of the trench to be excavated on the same side are distributed at equal intervals, and the positions of the vertical ribs 1 on the contour lines on both sides of the trench to be excavated correspond to each other; circular holes 6 are provided on the upper part of the vertical ribs 1 and on the steel retaining plate 4; by evenly providing circular holes on the upper part of the vertical ribs and the upper part of the steel retaining plate, when the soil layer is pulled out in the later stage, the vertical ribs and the steel plate are pulled out mechanically by passing the steel wire rope through the corresponding circular holes on the vertical ribs and the steel retaining plate; a purlin structure is provided between the two relatively positioned foundation combinations; the purlin structure includes a steel bull leg 5 on the vertical rib 1, two braces 2 and two cross braces 3; the two cross braces 2 span over and are fixed on the two steel bull legs 5 on the same purlin structure, and the two cross braces 3 are located between the two purlin structures, and the two ends of the cross braces 3 are welded and fixed to the corresponding parts of the braces 2.

[0040] Working principle and usage process of this embodiment

[0041] In the construction of trenches designed for deeper excavation, under the premise of meeting structural safety, the two channel steels or H-shaped steel cross braces 3 and the brackets 5 on both sides of the trench can be fully utilized to form a trench support structure node. The trench support structure node realizes the support system of the pipeline trench through the transverse retaining plate 5 and the brace 2, thereby realizing trench excavation, which is very practical.

[0042] In trench construction with an excavation depth of less than 3 meters, an excavated soil layer mainly consisting of old clay, and a shallow trench depth, on the premise of meeting structural safety, two channel steels or H-shaped steel vertical ribs 1 and a transverse retaining plate 5 on the same side of the trench can be used to form a basic combination of the support system. Only this simple structure is used for support, reducing the purlin system. During the trench excavation process, protection can be achieved as the trench is excavated, thereby improving work efficiency, reserving a larger working space for pipeline installation, and thus improving safety.

[0043] After the construction is completed, pass the wire rope through the circular hole 6, use the excavator to pull the vertical rib 1 and the horizontal steel plate 4 out of the soil layer, and proceed to the next construction.

[0044] At this point, the function of the present invention is fully realized, which can greatly save the cost of livestock and poultry breeding and effectively avoid food waste.

[0045] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0046] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A shallow trench support method for digging and protecting at the same time, characterized in that The following steps are involved: Step 1: Ordinary channel steel or H-shaped steel is used as vertical ribs, and steel plates are used as steel retaining walls; Step 2: Use a machine to statically press the vertical ribs into the soil layer; that is, the vertical ribs are pre-pressed into the contour line of the trench to be excavated in advance by the machine, and the vertical ribs of the contour line of the trench to be excavated on the same side are evenly spaced, and the vertical ribs of the contour line of the trench on both sides correspond to each other; Step 3: Place the steel retaining plate in place along the soil side of the adjacent vertical ribs of the trench to be excavated on the same side, and clamp the steel retaining plate through the adjacent vertical ribs. The two adjacent vertical ribs and the corresponding steel retaining plate constitute a basic combination of the support system; multiple basic combinations are formed according to this process; Step 4: Mechanically excavate the trench to be excavated. During the downward excavation process, the steel retaining plates at the corresponding positions are statically pressed downward to provide support. Step 5: When the machine excavates to the specified depth, the purlins will be installed between the corresponding vertical ribs, and the steel retaining plate will be statically pressed down to the specified depth. Then, manual excavation of the trench will be carried out until the design elevation is reached. Step 6: After the construction is completed, pull the vertical ribs and steel plates out of the soil layer and proceed to the next construction; Circular holes are evenly arranged on the upper part of the vertical ribs and the upper part of the steel retaining plate. When the soil layer is pulled out in the later stage, the vertical ribs and the steel plate are pulled out mechanically by passing the steel wire rope through the corresponding circular holes on the vertical ribs and the steel retaining plate. In the step 3, the two steel retaining plates on the adjacent foundation assemblies on the same side are staggered with each other.

2. A shallow trench support method for excavation and protection according to claim 1, characterized in that: After the vertical ribs are pre-pressed, the portion of the vertical ribs exposed to the ground accounts for 1 / 3 to 1 / 4 of the length of the entire vertical rib.

3. A support structure formed by the support method for supporting a shallow trench as it is excavated according to any one of claims 1-2, comprising vertical ribs (1) located on both sides of the contour line (7) of the trench to be excavated, wherein the vertical ribs (1) are partially embedded in the soil at the trench to be excavated, and is characterized in that: The steel retaining plates (4) are placed on the back of the adjacent vertical ribs (1) on the same side of the trench to be excavated, and the steel retaining plates (4) are clamped by the adjacent vertical ribs (1), wherein two adjacent vertical ribs (1) and the corresponding steel retaining plates constitute a basic combination of a support system, wherein the two steel retaining plates (4) on the adjacent basic combination on the same side are staggered with each other; the vertical ribs (1) on the contour line of the trench to be excavated on the same side are distributed at equal intervals, and the positions of the vertical ribs (1) on the contour lines on both sides of the trench to be excavated are aligned. The invention relates to a method for preparing a purlin structure for a vertical rib (1) and a steel retaining plate (4); a circular hole (6) is provided on the upper part of the vertical rib (1) and the steel retaining plate (4); a purlin structure is provided between the two foundation assemblies at opposite positions; the purlin structure comprises a steel bull leg (5) located on the vertical rib (1), two opposite braces (2) and two transverse braces (3); wherein the two opposite braces (2) span over and are fixed to the two steel bull legs (5) on the same purlin structure, and the two transverse braces (3) are located between the two purlin structures, and the two ends of the transverse brace (3) are welded and fixed to the corresponding opposite braces (2).

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