CN111172833A

CN111172833A - Construction method of steep slope high embankment structure

Info

Publication number: CN111172833A
Application number: CN202010029567.7A
Authority: CN
Inventors: 罗强; 李元昊; 蒋良潍; 张良; 王腾飞; 梅明明; 谢涛
Original assignee: Southwest Jiaotong University
Current assignee: Southwest Jiaotong University
Priority date: 2020-01-13
Filing date: 2020-01-13
Publication date: 2020-05-19

Abstract

The invention discloses a method for constructing a steep slope high embankment structure, which comprises the following steps: A. on the steep slope foundation, cutting slopes along the line direction to form a foundation platform, and excavating pile pits on the foundation platform at intervals; B. embedding the pile foundation into a pile pit, and then installing a longitudinal beam on the foundation platform along the line direction; C. t-shaped components are arranged on the longitudinal beams at intervals along the line direction, and each T-shaped component comprises an upright post and a triangular rib plate; D. and (3) overlapping soil retaining plates on the longitudinal beams on the inner sides of the adjacent upright columns along the line direction, and then filling and compacting embankment filling soil on the two sides of the triangular rib plates and the inner sides of the soil retaining plates until the embankment surface. The embankment retaining structure is arranged on the basis of the foundation consisting of the pile foundation and the longitudinal beam, and the friction force between the triangular rib plates on the T-shaped component and the embankment filling soil balances the soil pressure acting on the soil retaining plate, so that the stability of the formed steep slope embankment is ensured. Small disturbance to the soil body of the steep slope foundation, high construction safety, small masonry amount and convenient operation.

Description

Construction method of steep slope high embankment structure

Technical Field

The invention relates to the technical field of roadbed engineering, in particular to a construction method of a steep slope high embankment structure.

Background

In recent years, the construction of infrastructures such as railways and roads in China is rapidly developed, wherein the construction engineering of areas with complex terrain and severe terrains plays a crucial role in promoting the modernization process of China. In mountainous areas with numerous mountains and rugged ravines, embankments are often required to be arranged on steep slope foundations. In the existing engineering construction, common steep slope embankment treatment measures and relevant action mechanisms thereof mainly comprise: 1) the steep slope embankment adopting the reinforced retaining wall mainly balances the soil pressure of the slope filling soil body acting on the retaining plate through the tension provided by the tie bars anchored in the stabilized soil body behind the wall. When the design is close to the vertical slope due to the restrictions of the terrain, the height of the embankment and the like, the structure has the advantages of small masonry amount, small occupied area and obvious advantages. 2) The steep slope embankment adopting the anchor pile plate wall balances the soil pressure mainly through the anti-skidding and anti-overturning force provided by the anchor piles embedded into the foundation soil body. Compared with the traditional gravity type supporting and retaining structure, the structure reduces the requirement on the strength condition of the slope foundation and has smaller self weight. Although the existing various steep slope embankment structures in the prior stage can meet the requirements of different working conditions to a certain extent, the existing steep slope embankment structures have defects to a certain extent due to the difference of respective structural characteristics and applicable conditions, and the economic loss caused by the related steep slope embankment diseases is not visible.

The current common diseases of the steep slope embankment mainly comprise: 1) the overall collapse of the embankment means that the filled embankment has poor stability and cannot continuously bear working load to collapse, and the embankment is frequently used in areas with poor terrain conditions such as steep slopes in mountainous areas and high fill road sections. 2) Embankment fender structure damages, and the concrete performance is: the wall body is prone to overturning and sliding caused by poor stability of the wall body, and the wall body is prone to cracking caused by overlarge external load and insufficient structural material strength. The resulting embankment stability problem can have a significant impact on engineering safety. 3) The uneven settlement of the embankment is overlarge and is mainly related to factors such as load size, soil body properties, construction process and the like, and the uneven settlement is strictly controlled to ensure the durability and safety of the engineering, so that the roadbed can bear the repeated load action of vehicles and resist various natural factors, and the normal operation of the line is ensured. Therefore, improvement and innovation are carried out on the conventional steep slope embankment structure, so that the method has certain practical significance for solving the problems of poor soil stability, complex construction process, large engineering masonry amount, high material cost and the like.

Disclosure of Invention

The invention aims to provide a construction method of a steep slope high embankment structure, which consists of two parts, namely a pile joist foundation and a rib anchor type retaining wall, can be used for arranging an embankment surface on a steep slope in a mountainous area, and has the advantages of reasonable stress, low cost, convenient construction and good stability of the filled embankment.

The technical scheme for realizing the purpose of the invention is as follows:

a method for constructing a steep-slope high embankment structure comprises the following steps:

A. on the steep slope foundation, cutting slopes along the line direction to form a foundation platform, and excavating pile pits on the foundation platform at intervals;

B. embedding the pile foundation into a pile pit, and then installing a longitudinal beam on the foundation platform along the line direction; the lower part of the pile foundation is rigidly connected with the top of the longitudinal beam, and the outer side of the longitudinal beam is also provided with a limiting flange;

C. t-shaped components are arranged on the longitudinal beam at intervals along the line direction; the T-shaped component comprises an upright post and a triangular ribbed plate, wherein the upper side of the triangular ribbed plate is horizontal, and the vertical side of the triangular ribbed plate is connected to the inner side of the upright post; the outer side of the upright post is tightly attached to the inner side of the limiting flange, and the bevel edge of the triangular rib plate is attached to the steep slope foundation;

D. and (3) overlapping soil retaining plates on the longitudinal beams on the inner sides of the adjacent upright columns along the line direction, and then filling and compacting embankment filling soil on the two sides of the triangular rib plates and the inner sides of the soil retaining plates until the embankment surface.

Further, in step C, the upright post of the T-shaped member is aligned with the axis of the pile foundation.

And D, before filling the compacted embankment, arranging an inverted filter layer on the inner side of the soil retaining plate.

And D, excavating steps on the steep slope foundation before filling the compacted embankment with soil.

And step D, further comprising the step of arranging a transverse drainage slope on the embankment surface and arranging a longitudinal drainage lateral ditch on the inner side of the embankment surface.

The invention has the beneficial technical effects that:

the embankment retaining structure is arranged on the basis of the pile foundation and the longitudinal beam, and the friction force between the triangular rib plates on the T-shaped component and the embankment filling soil balances the soil pressure acting on the soil retaining plate, so that the stability of the formed steep slope embankment is ensured.

And secondly, the disturbance to the soil body of the steep slope foundation is small, the construction safety is high, the masonry amount is small, and the operation is convenient.

And thirdly, all components of the structure can be cast in place or prefabricated and assembled, so that comparison and selection of different engineering schemes are facilitated, the construction period can be shortened, and the cost can be reduced.

Drawings

Fig. 1 is an isometric view of a steep high embankment structure of the present invention prior to fill.

Fig. 2 is an isometric view of a steep high embankment structure of the present invention after it has been filled.

Fig. 3 is a structural cross-sectional view of the steep-slope high embankment structure of the present invention.

Fig. 4 is a plan view of the steep high embankment structure of the present invention.

The foundation comprises a steep slope foundation 1, a foundation platform 1a, a pile pit 1b, a pile foundation 2, longitudinal beams 3, a limiting flange 3a, a T-shaped component 4, a stand column 4a, a triangular rib plate 4b, a soil retaining plate 5, filling 6, an embankment surface 6a and a reverse filter layer 7.

Detailed Description

A construction method of a steep-slope high embankment structure comprises the following steps:

A. on the steep slope foundation 1, slope cutting is carried out along the line direction to form a foundation platform 1a, and pile pits 1b are excavated on the foundation platform 1a according to the designed interval;

B. burying a pile foundation 2 in a pile pit 1b, and installing a longitudinal beam 3 on the platform 1a along the line direction; the pile foundation 2 is rigidly connected with the longitudinal beam 3, and the outer side of the longitudinal beam 3 is provided with a limiting flange 3 a;

C. t-shaped members 4 with triangular rib plates are arranged on the longitudinal beams 3 along the line direction according to the designed interval, the outer sides of the upright posts 4a of the T-shaped members 4 are tightly attached to the inner sides of the limiting flanges 3a, and the upper edges and the lower edges of the triangular rib plates 4b of the T-shaped members 4 are horizontally attached to the steep slope foundation 1;

D. and (3) overlapping the retaining plates 5 on the longitudinal beams 3 in a layering manner on the inner sides of the adjacent upright columns 4a along the line direction, and then filling and compacting embankment filling 6 on two sides of the T-shaped members 4 and the inner sides of the retaining plates 5 in a layering manner until an embankment surface 6a is formed.

In the above technical solution, if the design intervals between the pile pit 1b and the T-shaped member 4 are the same, the vertical column 4a of the T-shaped member 4 should be aligned with the axis of the pile foundation 2.

In addition, a reverse filtering layer 7 can be arranged between the embankment filling 6 compacted by layered filling and the soil blocking plate 5. Before the embankment filling 6 is compacted by layered filling, steps can be dug on the steep slope foundation 1, and the width of the steps is usually not less than 2 m. After the embankment surface 6a is constructed, the embankment surface 6a can be further provided with a transverse drainage slope, and the inner side of the embankment surface 6a is provided with a longitudinal drainage lateral ditch so as to meet the drainage requirement.

Claims

1. A method for constructing a steep-slope high embankment structure is characterized by comprising the following steps:

A. on the steep slope foundation (1), slope cutting is carried out along the line direction to form a foundation platform (1a), and pile pits (1b) are excavated on the foundation platform (1a) at intervals;

B. embedding a pile foundation (2) into a pile pit (1b), and then installing a longitudinal beam (3) on a foundation platform (1a) along the line direction; the lower part of the pile foundation (2) is rigidly connected with the top of the longitudinal beam (3), and the outer side of the longitudinal beam (3) is also provided with a limiting flange (3 a);

C. t-shaped components (4) are arranged on the longitudinal beam (3) at intervals along the line direction; the T-shaped component (4) comprises a vertical column (4a) and a triangular rib plate (4b), wherein the upper side of the triangular rib plate (4b) is horizontal, and the vertical side is connected to the inner side of the vertical column (4 a); the outer side of the upright post (4a) is tightly attached to the inner side of the limiting flange (3a), and the bevel edge of the triangular rib plate (4b) is attached to the steep slope foundation (1);

D. and (3) overlapping soil retaining plates (5) on the inner sides of the adjacent columns (4a) along the direction of the road on the longitudinal beams (3), and then filling and compacting embankment filling soil (6) on the two sides of the triangular rib plates (4b) and the inner sides of the soil retaining plates (5) until reaching the embankment surface (6 a).

2. A construction method of a steep high embankment structure according to claim 1, wherein in step C, the columns (4a) of the T-shaped members (4) are aligned with the axis of the pile foundations (2).

3. The method for constructing a steep high embankment structure according to claim 1, wherein the step D further comprises installing a reverse filtration layer (7) inside the soil guard plate (5) before filling the compacted embankment fill (6).

4. The method for constructing a steep slope high embankment structure according to claim 1, wherein the step D further comprises excavating steps on the steep slope foundation (1) before filling the compacted embankment filling soil (6).

5. The method for constructing a steep-slope high embankment structure according to claim 1, wherein step D further comprises providing a lateral drainage slope on the embankment surface (6a) and a longitudinal drainage lateral ditch on the inner side of the embankment surface (6 a).