CN217105151U - Compound high slope supporting construction - Google Patents

Abstract

The utility model discloses a compound high slope supporting construction, including buttress formula barricade, prestressed anchorage cable and the miniature stake of basement, set up two rows of miniature stakes of basement in buttress formula barricade bottom to the miniature stake of two rows of basement combination buttress formula barricade structures that set up, it consolidates through setting up the prestressed anchorage cable on the buttress formula barricade again, carries out effectual strutting to the condition that the excavation and filling handing-over position and the unsatisfactory requirement of barricade basement foundation bearing capacity, satisfies the requirement that the side slope was strutted.

Description

Compound high slope supporting construction

Technical Field

The utility model relates to a compound high slope supporting construction relates to side slope support engineering technical field.

Background

With the rapid development of the engineering construction field in recent years, permanent high slope protection and reinforcement engineering frequently appears in engineering construction projects and is an important component of the engineering construction projects; the engineering geological conditions vary greatly due to different regions. Along with the continuous development of economy, mountain engineering construction projects are more and more. In engineering practice, many retaining walls are located at the excavation and filling joint part, or the bearing capacity of the retaining wall base foundation does not meet the design requirements, foundation treatment is required or a firmer supporting design scheme is required to be changed, so that the period is prolonged, the construction difficulty is increased and the cost is increased. Considering that high slope support needs to integrate site slope geological conditions, specific height of the slope, surrounding environment of the slope top of the slope and the like, and aiming at the situation that the slope after excavation has stratum change and landslide, the conventional single support mode cannot meet the requirements of high slope support.

In summary, the current supporting mode cannot meet the requirements aiming at the comprehensive factors of slope supporting and the distribution condition of foundation soil layers.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a compound high slope supporting construction, through the composite construction of counterfort formula barricade, prestressed anchorage cable, basement micropile, satisfies the requirement of side slope support.

In order to realize the technical purpose, the technical effect is achieved, the utility model discloses a realize through following technical scheme:

a composite high slope supporting structure comprises a buttress type retaining wall, a prestressed anchor cable and base micro piles, wherein two rows of base micro piles are arranged at the bottom of the buttress type retaining wall, a connection transition section of the buttress type retaining wall and the base micro piles is a C20 plain concrete cushion layer, a toe board and a wallboard of the buttress type retaining wall are close to the outside of a slope, a heel board is close to the inside of the slope, the outside of the prestressed anchor cable is anchored with the wallboard, the inside of the prestressed anchor cable extends to the slope, and an included angle of 15-25 degrees is formed between the external of the prestressed anchor cable and the horizontal plane; the counterfort retaining wall is provided with a gravel reverse filter layer and a water drainage hole.

Further, buttress-type retaining wall is C25 concrete retaining wall.

The utility model has the advantages that:

the utility model discloses a compound high slope supporting construction, including buttress formula barricade, prestressed anchorage cable and the miniature stake of basement, set up two rows of miniature stakes of basement in buttress formula barricade bottom to two rows of miniature stakes of basement combine buttress formula barricade structure, set up the prestressed anchorage cable reinforcement on buttress formula barricade again, carry out effectual strutting to the circumstances such as the unsatisfactory requirement of foundation bearing capacity at the bottom of filling and digging handing-over position and barricade, satisfy the requirement that the side slope was strutted.

Of course, it is not necessary for any particular product to achieve all of the above-described advantages at the same time.

Drawings

Fig. 1 is a schematic structural view of a composite high slope supporting structure according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a buttress retaining wall, a prestressed anchor cable and a foundation micropile according to an embodiment of the present invention;

in the drawings, the reference numerals correspond to the following components:

1-buttress type retaining wall, 101-C20 plain concrete cushion layer, 102-gravel reverse filter layer, 103-water drainage hole, 2-prestressed anchor cable and 3-base micro pile.

Detailed Description

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Example 1

As shown in fig. 1-2

A composite high slope supporting structure comprises a buttress type retaining wall 1, a prestressed anchor cable 2 and base micro-piles 3, wherein two rows of base micro-piles 3 are arranged at the bottom of the buttress type retaining wall 1, a connection transition section of the buttress type retaining wall 1 and the base micro-piles 3 is a C20 plain concrete cushion layer 101, a toe board and a wallboard of the buttress type retaining wall 1 are close to the outside of a slope, a heel board is close to the inside of the slope, the outside of the prestressed anchor cable 2 is anchored with the wallboard, the inside of the prestressed anchor cable extends to the slope, and an included angle of 15-25 degrees is formed between the inside of the prestressed anchor cable 2 and the horizontal plane; the counterfort retaining wall 1 is provided with a gravel reverse filtering layer 102 and a water drainage hole 103.

The counterfort retaining wall 1 is a C25 concrete retaining wall.

Two rows of base micro piles are arranged at the bottom of the counterfort type retaining wall, the two rows of base micro piles are combined with the counterfort type retaining wall structure, and then the counterfort type retaining wall is reinforced by setting a prestressed anchor cable on the counterfort type retaining wall, so that the excavation and filling connection position and the conditions that the bearing capacity of the retaining wall base foundation does not meet the requirements and the like are effectively supported, and the requirements of slope support are met.

Example 2

The composite high slope supporting structure comprises a buttress retaining wall, a prestressed anchor cable and a foundation micro pile;

buttress-type retaining wall: the retaining wall is cast by adopting a plain concrete integral formwork, and the concrete grade is C25;

the retaining wall foundation is constructed by adopting segmented excavation (the length of each segment is not more than 25m or the length of each expansion joint is required to be separated), excavating one segment, and immediately erecting and pouring the formwork; the foundation trench should be kept dry, accumulated water in the foundation trench should be drained at any time in rainy days, all the foundation soil soaked by water should be removed, and the foundation soil is tamped to the required elevation by centimeter stones (or gravels); the substrate needs to enter the supporting layer to be not less than 1.0m while meeting the design buried depth requirement;

the retaining wall requires every 25m interval (the specific interval can be adjusted according to the actual field or according to the design requirement, etc.), an expansion joint with the width of 2-3 cm is reserved, asphalt hemp threads or asphalt-coated wood boards are filled in the joint along the inner, outer and top edges of the wall, and the filling depth is not less than 200 mm;

the concrete curing strength of the wall body reaches 80% or more, and the wall body can be backfilled, and before the wall back is filled with soil, the earth surface plant layer, the ploughing soil and the weak soil need to be removed;

the filler is preferably crushed rock with good gradation, when the filler is mainly cohesive soil or completely weathered rock stratum, the filler is preferably mixed with a certain proportion of crushed stone, and the volume ratio is as follows: 7:3 of broken stone; the filler can not be selected from mucky soil, plowed soil, soft to plastic cohesive soil, silt and the like.The internal friction angle of the backfill material is more than 30 degrees, and the gravity is more than or equal to 19.5KN/m ³ The filler is tamped layer by layer (the thickness of the layer is preferably 0.5m), the tamping is uniform, and the tamping coefficient is not less than 0.92;

substrate micropile: the miniature pile needs to be formed at one time, the reinforcement cage needs to be manufactured into a whole root, and the pile is formed by grouting at the bottom of the hole after the hole is formed and the reinforcement cage is placed.

Adopting an engineering geological drilling machine to perform pore-forming construction:

(1) the pile body rib body of the miniature pile is made of 3C 20 steel bars (HRB400) and has the length of 12.0 m;

(2) the micro pile is preferably formed by a geological drilling machine, the hole diameter of a drilled hole is 180mm, the hole wall of the formed hole needs to be smooth, the diameter of the hole wall meets the requirement, and the hole needs to be cleaned after the hole is formed, so that the hole wall has no pollutants, and the bonding strength between cement paste and a rock body is ensured; if the hole collapse phenomenon occurs in the formed hole, corresponding measures (such as full casing follow-up or secondary hole forming) are required to be taken to ensure the quality of the formed hole;

(3) a pair of middle supports are arranged every 2m on the reinforcing steel bars of the pile body so that the reinforcing steel bars are in the middle in the drilled hole;

(4) when the steel bar is welded, double-side welding is adopted, and the lap joint length during welding is not less than 5 d;

(5) the surface of the adopted steel bar must not have oil stain, rust or rust removal before construction;

(6) grouting by adopting a secondary grouting technology from the bottom of the hole to the top until grout returns from the orifice; the primary grouting pressure is about 0.2MPa, secondary grouting is carried out about 2-3 hours after the primary grouting is finished, the grouting pressure is about 1.2-1.5 MPa, and the concrete grouting pressure is properly adjusted according to the actual situation on site; grouting needs to ensure that grout at the position of an orifice is densely filled, the using amount of grouting cement is not less than 70kg/m, the grouting adopts pure cement with a water-cement ratio (weight ratio) of 0.50-0.55, and the cement strength grade is PO 42.5;

(7) the plane position of the micro pile can be locally adjusted according to the actual situation of the field;

(8) quality acceptance and inspection requirements:

firstly, raw materials such as reinforcing steel bars, cement, auxiliary materials and the like are checked before construction;

the allowable deviation of hole positions is not more than 50mm, the error of the inclination angle of a drilled hole is not more than 3 degrees, and the length of the rod body is not less than the designed length;

thirdly, the allowable deviation of the aperture is between +20mm and-5 mm, and the allowable deviation of the depth is between +200mm and-50 mm;

(9) other parameters are performed according to the relevant specifications.

Pre-stressed anchor cables:

(1) anchor cable construction technical requirements

Firstly, performing an anchor cable anti-pulling test before construction, wherein the number of the tests is not less than 3, adjusting the tension value of the anchor cable and the length of the anchor section of the anchor cable in time according to the test result, and performing the anchor cable anti-pulling test according to the relevant standard;

secondly, the anchor cable is constructed by adopting a dry pore-forming process, the pore depth is 0.5-1.0 m higher than the designed depth, the drilling of the anchor cable cannot disturb the surrounding stratum, the pore-forming construction of the anchor cable is carried out, and when an unstable stratum (a stratum with easy-to-collapse pores) is encountered, casing wall protection drilling or other effective measures are adopted to ensure that the length of the anchor cable meets the design requirement;

and thirdly, accurately measuring and placing the position of the anchor hole according to a design drawing, wherein the longitudinal and transverse errors of the hole position are not more than +/-50 mm, and the skewness of the axis of the drill hole is not more than 3% of the length of the anchor rod. Before the anchor cable is placed in the drill hole, rock powder and soil scraps in the hole are removed completely.

(2) The anchor cable assembly and placement requirements are as follows:

firstly, an anchor cable body is a 1860-grade 15.2 steel strand, oil stains and rusty spots of the steel strand are removed, the steel strand is blanked strictly according to design requirements, the blanking length is greater than the design length by 1.0m, and the steel strand is arranged straightly;

secondly, the anchor cable isolation frames are arranged along the axis direction of the rod body, one isolation frame is arranged at intervals of 1.5m in the anchoring section, and one isolation frame is arranged at intervals of 2.0m in the free section;

thirdly, when the anchor cable body is placed, the rod body is prevented from twisting and bending, the primary grouting pipe is placed into the drilled hole along with the anchor cable, the distance between the head of the grouting pipe and the bottom of the drilled hole is 50-100 mm, and the placing angle of the rod body is consistent with the angle of the drilled hole;

fourthly, the anchor cable body cannot be knocked and hung with heavy objects after being placed.

(3) Grouting requirements:

firstly, anchor cable construction adopts secondary high-pressure grouting and a grouting leakage-repairing process, the cement consumption per meter is not less than 80kg, and the grouting leakage-repairing grouting is carried out until the wall surface is turned over and no water seepage phenomenon exists around an anchor hole; pure cement slurry is adopted for grouting (the cement grade is PO42.5, the water cement ratio is about 0.50-0.55, triethanolamine early strength agent accounting for 0.05% of the cement dosage is added, and the 28-day strength of the grouting body is not lower than 30 MPa);

secondly, immediately putting down a grouting pipe (simultaneously putting down along with the anchor cable) after hole cleaning is finished, then injecting pure cement slurry into the anchor hole by using a pressure pump, performing primary grouting until water and impurities in the drill hole are replaced out of the orifice and cement slurry flows out of the orifice, and plugging the orifice when the slurry flows out of the orifice;

thirdly, after primary grouting is finished for about 6 to 8 hours, plugging and compacting the orifice by using quick-setting cement, and performing secondary grouting at the grouting pressure of about 1.4 to 1.6 MPa;

the grouting slurry is uniformly stirred and used along with stirring, the slurry is used up before initial setting, and stones and impurities are prevented from being mixed into the slurry strictly;

fifthly, grouting is carried out for ensuring that cement paste is full without phenomena of overflowing from the inside to the outside, grouting operation is started and stopped for a long time in the midway, and a grouting pump and a grouting pipeline are lubricated by water or dilute cement paste during operation again;

sixthly, the number of the test blocks for testing the slurry strength is not less than 1 group per 15 anchor cables, and each group of test blocks is not less than 6;

(4) requirement for tensioning

Firstly, the strength of an anchoring body and an outer anchor pier reaches 80% of the design strength, the tensioning and locking can be carried out after the strength of a grouting body and the strength of pedestal concrete are both greater than 20MPa, the bearing surface of the pedestal is smooth and is vertical to the axis direction of an anchor rod, and the tensioning is carried out in a grading manner;

pre-tensioning for 1-2 times by taking 10-20% of the designed axial tension value of the anchor cable before formal tensioning of the anchor cable to ensure that the rod body is completely straight, all parts are tightly contacted, the anchor cable is kept for 10min when tensioned to a tensioning locking value of 1.1-1.15 times, then unloading is carried out to a locking load design value for locking, and compensation tensioning is carried out when the prestress loss after locking is more than 10% of the design value;

tensioning the anchor cables according to a certain program, wherein the tensioning sequence of the anchor cables needs to consider the mutual influence of the adjacent anchor cables, and the distance between the two tensioned anchor cables is not less than 2 times of the distance between the anchor cables during tensioning;

fourthly, after compensation tensioning and locking, when the grouting material reaches the designed strength, and after tensioning of the anchor cable is completed, cutting off redundant steel strands by using a grinding wheel machine.

(5) Corrosion resistance of anchor cable

Corrosion prevention of a free section: after rust and oil removal of each steel strand, coating lubricating oil or brushing anti-corrosion paint on the surface of the anchor cable at the free section for anti-corrosion treatment, then putting the anchor cable into a plastic sleeve, and winding and binding an engineering adhesive tape within a length of 100-200 mm from the end part of the sleeve at one side of the anchoring section for fixing;

anchoring section anticorrosion: after rust and oil removal of the steel strand, adopting cement mortar for corrosion prevention, and positioning the anchor cable in the middle of the anchor hole during construction, wherein the thickness of a cement mortar protective layer around the rod body is required to be not less than 35 mm;

fourthly, corrosion prevention of the anchor head: tensioning and locking an anchor cable, sealing after secondary grouting is finished, reserving a steel strand of 100mm from the anchor, and sealing C25 fine aggregate concrete according to the requirement of an anchor head, wherein the detailed drawing is shown in detail;

(6) quality acceptance and inspection requirements:

firstly, the raw materials such as steel strands, cement, auxiliary materials and the like are checked before construction;

the allowable deviation of hole positions is not more than 50mm, the error of the inclination angle of a drill hole is not more than 3 degrees, the length of the rod body is not less than the designed length, and the allowable deviation of the length of the sleeve of the free section is +/-50 mm;

thirdly, the allowable deviation of the aperture is between +20mm and-5 mm, and the allowable deviation of the depth of the hole is between +200mm and-200 mm;

(7) other parameters are performed according to relevant specifications.

The utility model discloses a compound high slope supporting construction, including counterfort formula barricade, prestressed anchorage cable and basement miniature stake, set up two rows of basement miniature stakes in counterfort formula barricade bottom to two rows of basement miniature stakes combine counterfort formula barricade structure, reinforce through setting up prestressed anchorage cable on the counterfort, carry out effectual strutting to the circumstances such as the unsatisfactory requirement of foundation bearing capacity at the bottom of filling and filling handing-over position and the barricade, satisfy the requirement that the side slope was strutted.

In the description herein, references to the description of "one embodiment," "an example," "a specific example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, to thereby enable others skilled in the art to best understand the invention for and utilize the invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims (2)

1. The utility model provides a compound high slope supporting construction which characterized in that: the wall-supporting retaining wall comprises a wall-supporting retaining wall, a prestressed anchor cable and substrate micro-piles, wherein two rows of substrate micro-piles are arranged at the bottom of the wall-supporting retaining wall, a connection transition section of the wall-supporting retaining wall and the substrate micro-piles is a C20 plain concrete cushion layer, a wall toe plate and a wall plate of the wall-supporting retaining wall are close to the outside of a side slope, a wall heel plate is close to the inside of the side slope, the external part of the prestressed anchor cable is anchored with the wall plate, the internal part of the prestressed anchor cable extends to the side slope, and an included angle of 15-25 degrees is formed between the external part of the prestressed anchor cable and the horizontal plane; the counterfort retaining wall is provided with a gravel reverse filter layer and a water drainage hole.

2. A composite high slope supporting structure as claimed in claim 1, wherein: the buttress type retaining wall is a C25 concrete retaining wall.

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