CN211006711U

CN211006711U - High groundwater level pipeline slot backfilling structure

Info

Publication number: CN211006711U
Application number: CN201921427566.7U
Authority: CN
Inventors: 王骏林; 白若男; 刘梅; 范洁; 赵玲; 赖龙隆; 曹明利; 张朴
Original assignee: China Construction Water Affairs Environmental Protection Co Ltd
Current assignee: China Construction Eco Environmental Group Co Ltd
Priority date: 2019-08-29
Filing date: 2019-08-29
Publication date: 2020-07-14
Anticipated expiration: 2029-08-29

Abstract

The application relates to a high underground water level pipeline groove backfilling structure which sequentially comprises a graded crushed stone layer, a first medium coarse sand layer, a second medium coarse sand layer, a first improved soil layer, a second improved soil layer and a roadbed from bottom to top; the first modified soil layer and the second modified soil layer are lime soil; the graded broken stone layer and the first medium grit layer are located below the pipeline, the second medium grit layer is located below the pipeline bottom elevation horizontal line to the pipeline horizontal central line, the first modified soil layer is located in the second medium grit layer top to the pipeline topmark high level line, the second modified soil layer is located above the first modified soil layer (4) to the pipeline topmark high level line more than 50 cm. The backfill structure of the high-underground water level pipeline groove has high engineering quality, and the used raw materials are cheap and easy to obtain.

Description

High groundwater level pipeline slot backfilling structure

Technical Field

The application relates to the technical field of municipal drainage pipe network engineering construction, in particular to a backfill structure for a trench of a high-underground water level pipeline.

Background

In the pipeline groove backfilling engineering, because the water content of the original soil excavated by the pipeline groove is higher, the backfilled soil is easy to have insufficient compaction degree, so that the quality problems of pipe network damage and the like are caused, the application is less, particularly in southern areas, the underground water level is high, most of soil has higher water content, the earthwork excavating the groove cannot meet the optimal water content requirement of the backfilled soil, the spring phenomenon easily occurs in the compaction process, and the compaction requirement cannot be met. Therefore, in the prior art, the pipeline trench is generally backfilled by using sand as a backfilling material, and the sand with different particle sizes is used for backfilling according to different parts of a pipeline. For example, in the current rural sewage treatment projects, because original soil meeting the conditions is difficult to find, the village pipe network groove backfilling design method is to backfill sand to 50cm above the pipe top. Although the current materials of the sand are high in price and easy to break goods and delay the construction period, most construction enterprises still adopt the sand to backfill the pipeline groove for the engineering quality. Therefore, a pipeline groove backfill structure is urgently needed, which can not only ensure the engineering quality, but also reduce the engineering cost.

SUMMERY OF THE UTILITY MODEL

The invention aims to provide a high underground water level pipeline groove backfill structure which is high in structural engineering quality and low in price and easy to obtain used raw materials.

The backfill structure for the trench of the high-groundwater-level pipeline is characterized by comprising a graded crushed stone layer, a first medium coarse sand layer, a second medium coarse sand layer, a first improved soil layer, a second improved soil layer and a roadbed from bottom to top in sequence; the first modified soil layer and the second modified soil layer are lime soil; the graded broken stone layer and the first medium grit layer are located below the pipeline, the second medium grit layer is located below the pipeline bottom elevation horizontal line to the pipeline horizontal center line, the first modified soil layer is located in the second medium grit layer top to the pipeline topmark high level line, the second modified soil layer is located above the first modified soil layer to the pipeline topmark high level line more than 50 cm.

Preferably, the limestone soil is soil mass formed by mixing lime and pipeline groove raw soil according to the volume ratio of 3: 97-8: 92.

Preferably, the pipeline trench original soil is soil obtained by screening earthwork excavated from a pipeline by using a 10 × 10mm screen; the lime is slaked lime.

Preferably, the thickness of the graded crushed stone layer is 25 cm-35 cm, and the compactness is 90% -95%.

Preferably, the thickness of the first medium coarse sand layer is 18cm-22cm, and the compactness is 88% -92%.

Preferably, the degree of compaction of the second medium coarse sand layer is 94-98%.

Preferably, the degree of compaction of the first improvement soil layer is 94% to 98%.

Preferably, the degree of compaction above the second amended soil layer pipeline is between 84% and 88%; the compaction degree of other parts is 90-94%.

Preferably, the particle size of the medium coarse sand in the first medium coarse sand layer is 0.5 mm-1 mm; the grain size of the coarse sand in the second medium coarse sand layer is 0.3-0.5.

Through the technical scheme, the utility model provides a structure is backfilled to high groundwater level pipeline slot, should backfill the structure make full use of the soil that the slot was excavated, reduced the moisture content of soil with the help of the effect of lime to greatly reduced the cost under the prerequisite of guaranteeing engineering quality, reduced because of the hidden danger that the quality problems of sand brought, absorbed the earthwork that the slot was excavated simultaneously, satisfied the environmental protection requirement.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

FIG. 1 is a schematic diagram of a trench backfill structure for a pipeline with a high ground water level.

Reference numerals

1. Graded crushed stone layer

2. First medium coarse sand layer

3. Second medium coarse sand layer

4. First modified soil layer

5. Second improved soil layer

6. Road bed

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

According to the present disclosure, as shown in fig. 1, the present disclosure provides a trench backfill structure for a high groundwater level pipeline, which sequentially comprises, from bottom to top, a graded crushed stone layer 1, a first medium coarse sand layer 2, a second medium coarse sand layer 3, a first modified soil layer 4, a second modified soil layer 5 and a roadbed 6; the first modified soil layer 4 and the second modified soil layer 5 are lime soil; the graded broken stone layer 1 and the first medium coarse sand layer 2 are located below the pipeline, the second medium coarse sand layer 3 is located below the pipeline bottom elevation horizontal line to the pipeline horizontal central line, the first modified soil layer 4 is located in the second medium coarse sand layer 3 is located above the pipeline top elevation high level line, and the second modified soil layer 5 is located above the first modified soil layer 4 is located above the pipeline top elevation high level line by more than 50 cm.

Preferably, the limestone soil is soil mass formed by mixing lime and pipeline groove raw soil according to the volume ratio of 3: 97-8: 92. The volume ratio of the lime to the raw soil of the pipeline groove is further preferably 5: 95.

Preferably, the thickness of the graded crushed stone layer 1 is 25 cm-35 cm, and the compactness is 90% -95%.

Preferably, the thickness of the first medium coarse sand layer 2 is 18cm-22cm, and the compactness is 88% -92%.

Preferably, the degree of compaction of the second medium coarse sand layer 3 is 94% to 98%.

Preferably, the degree of compaction of the first improvement soil layer 4 is 94% to 98%.

Preferably, the degree of compaction above the second topsides 5 pipeline is 84% to 88%; the compaction degree of other parts is 90-94%.

Preferably, the grain size of the medium coarse sand in the first medium coarse sand layer 2 is 0.5 mm-1 mm; the grain diameter of the coarse sand in the second middle coarse sand layer 3 is 0.3 mm-0.5 mm.

According to the method, before the pipeline trench is formally backfilled and worked, a well section is selected as a test section. And (3) excavating a pipeline groove to the height of the bottom of the pipe for the stratum with high underground water level, and filling a soft soil foundation which is 30cm below the bottom of the pipe, wherein graded broken stones are adopted as filling materials, and the compaction degree of the graded broken stone layer 1 is 93%. Laying a first medium-coarse sand layer 2 on the graded crushed stone layer 1 as a foundation, sieving raw materials before laying, filtering impurities such as soil blocks in medium-coarse sand, properly wetting the sand to ensure compactness, wherein the laying thickness of the medium-coarse sand is preferably 5-10cm higher than the elevation of the pipe bottom, performing water compaction on the sand foundation by adopting a spraying mode after laying is completed, and simultaneously leveling and checking an elevation soft soil stratum, wherein the thickness of the first medium-coarse sand layer 2 is 20cm after compaction, and the compaction degree is 90%. And laying a second medium coarse sand layer 3 on the first medium coarse sand layer 2 to a position below the horizontal central line of the pipeline, wherein the compactness of the second medium coarse sand layer 3 is 96%, and tamping is carried out by adopting a water-tamping auxiliary small-sized vibrator. And then, installing the pipeline, and encapsulating the pipeline joint part by adopting C15 concrete, wherein the encapsulation height is more than 10cm above the top of the pipeline.

According to the present disclosure, after the pipeline installation, backfilling a first modified soil layer 4 and a second modified soil layer 5, wherein the modified soil is lime soil, and the lime soil is mixed with the soil according to a volume ratio of lime to soil of 5:95, the concrete operations are as follows: processing and screening excavated soil to obtain a part which has less impurities and is close to the original soil, wherein the water content of the original soil is not higher than 10% of the optimal water content; arranging quicklime digestion sites around the grooves, curing the quicklime three days in advance, sieving the cured quicklime after the curing is finished, and removing blocks which do not meet the requirements; and then mixing the digested lime with the screened qualified raw soil, wherein the mixing times are 5-6 times, and backfilling the pipeline groove of the mixed lime soil.

According to the method, the first improved soil layer 4 is backfilled to the elevation of the top of the pipe, the backfilling height is less than 20cm each time, a small vibration machine is adopted for tamping and rolling after backfilling, the improved soil body is compacted for 2-4 times, the compaction degree of the first improved soil layer 4 is 96%, and the machine is prevented from touching the pipe during compaction. Backfilling the second layer of improved soil to 50cm above the top of the pipe, repeating the above operations, and compacting for 2 times by using a small machine right above the pipeline, wherein the compaction degree is 86%; compacting the other parts for 3 times, wherein the degree of compaction is 92%. And detecting the compacted material and the method adopted by the test section, and carrying out backfill work of the normal pipe section after the standard is met.

According to the utility model provides a pair of structure is backfilled to high groundwater level pipeline slot, make full use of excavation soil has reduced soil moisture content with the help of the effect of lime, greatly reduced the cost under the prerequisite of guaranteeing engineering quality, reduced the hidden danger that brings because of the quality problems of sand, absorbed the earthwork that the slot excavated simultaneously, satisfied the environmental protection requirement.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. The backfill structure for the trench of the high underground water level pipeline is characterized by sequentially comprising a graded crushed stone layer (1), a first medium coarse sand layer (2), a second medium coarse sand layer (3), a first improved soil layer (4), a second improved soil layer (5) and a roadbed (6) from bottom to top; the first modified soil layer (4) and the second modified soil layer (5) are lime soil; the graded broken stone layer (1) and the first medium grit layer (2) are located below the pipeline, the second medium grit layer (3) is located below the pipeline bottom elevation horizontal line to the pipeline horizontal center line, the first modified soil layer (4) is located in the second medium grit layer (3) top to the pipeline top standard high level line, the second modified soil layer (5) is located above the first modified soil layer (4) to the pipeline top standard high level line more than 50 cm.

2. The backfill structure according to claim 1, characterized in that the graded crushed stone layer (1) has a thickness of 25-35 cm and a degree of compaction of 90-95%.

3. The backfill structure according to claim 1, characterized in that said first medium grit layer (2) has a thickness of between 18 and 22cm and a degree of compaction comprised between 88 and 92%.

4. The backfill structure according to claim 1, characterized in that the degree of compaction of the second medium coarse sand layer (3) is between 94% and 98%.

5. The backfill structure according to claim 1, characterized in that the compaction of the first improving soil layer (4) is between 94% and 98%.

6. The backfill structure according to claim 1, characterized by a degree of compaction above the secondary amended soil layer (5) pipe of 84-88%; the compaction degree of other parts is 90-94%.

7. The backfill structure according to claim 1, characterized in that the medium grit in the first medium grit layer (2) has a particle size comprised between 0.5mm and 1 mm; the grain diameter of the coarse sand in the second medium coarse sand layer (3) is 0.3 mm-0.5 mm.