JPH0749658B2 - Construction method of steep slope embankment - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement in a method of constructing a steep slope embankment by winding a reinforcing material. More specifically, in the method of constructing steeply sloped embankments by sequentially stacking them by winding up reinforcements for civil engineering, there is a large degree of freedom that the construction direction and position of each step are not constrained, and a method of constructing steeply sloped embankments by a simple construction method. Regarding

[Prior art] When constructing a flat surface with soil on a slope to construct a road or residential land, in order to maximize the area of the site to be constructed with respect to the site area of the foundation, the slope is It is necessary to make it steep. However, in order to safely use such steep embankments as roads and residential land, the built embankments must be stable and free from collapse. Various construction methods have been proposed as a method for constructing such a stable steep slope embankment.

One of the construction methods for such steep slope embankment is the embankment construction method involving the inclusion of a reinforcing material. This construction method lays and lays a civil engineering reinforcement material called geotextile, scatters earth and sand on it, piles up a slope molding material such as sandbags on the slope to reinforce, and after rolling and embanking these, Reinforcing the reinforcing material along the slope, wrapping the embankment material, protecting the slope and reinforcing the embankment to build the first embankment, repeating this operation in sequence and stacking to build a steep slope embankment. Is.

[Problems to be Solved by the Invention] Since the embankment construction method involving the inclusion of the reinforcing material can construct a stable steep slope embankment with a relatively simple operation, it can be constructed everywhere in the field of civil engineering in recent years. And its effects have been confirmed.

By the way, in this construction method, conventionally, the method as shown in FIG. 1 has been exclusively used. That is, when laying and constructing the reinforcing material, the reinforcing material 1 is prepared. The reinforcing material 1 is composed of a laying portion 1a laid on the lower portion of the embankment, a slope portion 1b contacting the slope, and a rewinding portion 1c which is rewound on the upper portion and covers the upper surface of the embankment.
According to the design of each step, the reinforcing material is cut to a length including the laying part, the slope and the rewinding part length ₃ , the reinforcing material is laid on the design step, and the slope forming material 2 and the embankment 3 are placed on the laying part 1a. After the embossing is performed at the design pitch with, the reinforcing material is folded back along the slope and the top surface of the embankment, and a part of the embankment is covered with the slope portion 1b and the winding portion 1c of the reinforcing agent.

Next, when constructing the next stage, install the reinforcement section 1a
Is installed right above the reinforcing material rewinding portion 1c of the lower stage correctly, and normally, the rewinding portion 1c of the lower reinforcing material and the laying portion 1a of the reinforcing material immediately above are connected to a connecting auxiliary material such as a joint pipe or a connecting jig. Connect and fix with 4 (hereinafter referred to as joint material),
Then, the rear end of the upper laying part is tensioned by using a machine or a tool to shape the slope, and the temporary reinforcement of the upper tier is temporarily fixed with the temporary fixing piles 5 as one step. The method of completing the reinforced embankment was taken.

However, since the connection work with the joint material 4 is a temporary work for shaping the slope, since the work is complicated and a disposable joint material is required, Not only is it economically disadvantageous in terms of material cost, labor cost, and long construction time, but it is also necessary to accurately align the reinforcing materials in the upper and lower layers in the width direction. The failure of material construction cannot be corrected on the way and extends to the top stage. In addition, in steep slope embankments other than straight walls, which are often used for vegetation walls, slopes are used to accommodate bending in the wall extension direction, extension length of each layer that occurs when forming curved walls, and changes in the laying direction. Although it is inevitable to cut and discard the standard width of the reinforcing material and the joint member due to the above, it is necessary to make it disappear when the bend R is small or when high wall construction is performed. Therefore, in addition to the economic problems such as loss of materials other than the above, increase in work steps, extension of construction period, etc., it is related to the essence of the reinforcement embankment method such as slope deformation after construction due to defective molding. There is inconvenience.

In the conventional method, the rewound part of the reinforcing material is shorter than the laying part and covers only part of the embankment, so that it does not have the reinforcing effect of the embankment itself, and the laying part 1a of the next-stage reinforcing material and the joint material. It was connected and fixed with, the slope was shaped by tensioning the rear end of the upper laying part, and the embankment was reinforced,
For this reason, connection with a joint material was necessary.

In addition, in this method of winding the reinforcing material, the embankment wound in the reinforcing material is piled up successively, but in the conventional method, the rewinding portion 1c of the lower reinforcing material and the laying portion 1a 'of the reinforcing material immediately above are wide. Contact over an area. Since the reinforcing material usually has a mesh structure, a grid structure, a knitted fabric structure, etc., it provides an interlocking effect to soil, but the friction resistance of the reinforcing materials is not sufficient, and sliding motion along the contact surface of the reinforcing material is not sufficient. There was concern, and fixing with joint materials also had the effect of blocking this.

The inventors of the present invention, except for the above-mentioned drawbacks in the conventional method, studied the method of simplifying the process, saving the material, and constructing a stable steep embankment, and as a result, in the conventional method, only a part of the embankment was obtained. By setting the length of the rewound part of the reinforcing material that covered the to a specific length, by making it a reinforcing part rather than a simple rewound part, a tension operation for embankment stability can be performed without using a joint material. I found that I could do it.

In addition, when building the embankment after the second step, after loading the slope forming material on the reinforced portion of the reinforced material, lift the end of the laid portion and place it between the reinforcement portion of the directly lower reinforcing material. By inserting and filling the embankment material, and then rolling and spreading the slope forming material and the embankment material, the contact between the reinforcing materials is minimized, and by the winding structure in which the reinforcing material is fixed by the embankment itself, It is possible to firmly fix the reinforcing material without using a joint material or the like, and it is possible to completely eliminate the drawback caused by eliminating the use of the joint material. In this way, by adopting the construction method of the present invention which is completely different from the conventional method in which the use of a joint material is essential, it is possible to lay the reinforcing material in each step without mutual restraint in the direction and position. The inventors have found a method capable of constructing a stable steep embankment and reached the present invention.

[Means for Solving the Problem] That is, the present invention is to roll the embankment by rolling with a slope molding material and embankment on the expanded and reinforced civil engineering reinforcement material, and then rewinding the reinforcement material along the slope and the top surface of the embankment. In the method of constructing a single-step embankment by covering the upper surface of the formed embankment with a reinforcing material, and repeating this operation in sequence to construct a steep slope embankment with multiple steps, the length of the reinforcing portion of the reinforcing material is laid. At least 100% or more of the length, and at the time of embankment construction after the second step, after loading the slope forming material on the reinforced material laying part, lift the end of the laying part and raise it immediately below. This is a method of constructing a steep slope embankment, which is characterized in that a filling material is inserted and filled between the reinforcing material and a reinforcing portion, and then the slope forming material and the filling material are compacted and spread.

Reinforcing material used in the present invention is laid under the embankment, after roll compaction with the embankment and slope forming material and embankment, rewind along the slope and cover the upper surface of the formed embankment. It has a function to protect and reinforce the embankment, and a cloth-like fiber material for water-permeable soil stabilization, which has such an effect, has been widely used in recent years called geotextile. Examples of such geotextiles or similar materials include woven fabrics, non-woven fabrics, composites thereof, mats, nets, lattices, foam sheets, and composites of the above various materials.

In the present invention as well, any of such geotextiles can be used as a reinforcing material, but the reinforcing material used in the present invention can be a plastic net or a grid-like material in addition to a fiber product. In particular, grid-shaped products are also called geogrids, and the material itself has excellent strength and chemical stability, and its unique shape does not hinder the continuity of the soil and gives an interlocking effect. Is especially excellent as

The reinforcing material is composed of a portion laid on the bottom of the embankment, a portion in contact with the slope, and a portion that is rolled up to cover the upper surface of the embankment and is used for reinforcing the embankment. In the present invention below, the portion to be laid at the bottom of the embankment is a laying portion 1A, the portion in contact with the slope is the slope portion 1B, and is rewound on the upper surface of the embankment, and the portion used for reinforcing the embankment is the reinforcing portion 1C. Call.

The reinforcing material is the length L ₁ of the laid part 1A according to the design of each step,
Cut to a length that includes the length L _{2 of} the slope 1B and the length L ₃ of the reinforcement 1C (hereinafter referred to as the pitch), lay the stake 1A on the design stage, and cut the stake on the stake 1A. After compacting the surface forming material 2 and the embankment 3 to the design pitch, rewind the reinforcing material along the slope and the upper surface of the embankment, and cover the embankment with the slopes 1B and 1C of the reinforcing agent. Reinforce the embankment by tensioning the end in the direction opposite to the slope. At this time, the length L ₃ of the reinforcing portion 1C is at least 100% or more of the length L ₁ of the laying portion 1A, preferably 2
It is necessary to set it to 00% or more. If the length of the reinforcing portion is shorter than the above range, it is difficult to tighten the end portion of the reinforcing portion, and even if it is tightened, it cannot be fixed in a tensioned state. Laying reinforcements,
Since this must be joined to the joint material to tension the rear end of the upper laying portion, the above-mentioned construction problems associated with the joint material joining work cannot be avoided.

In the present invention, by specifying the relationship between the length of the reinforcing portion and the length of the laying portion, it is possible to tension the reinforcing material without using a joint material, and the reinforcing material wound on the upper portion directly fills the embankment. The effect of reinforcement can be given, and it has become possible to simplify the process and expand the degree of freedom in construction.

As the slope forming material in the present invention, sandbags are usually used, and as the sandbags, vegetative sandbags, slope-formed products such as iron and concrete are used, and vegetative sandbags are particularly preferable. Several layers of soil, usually around 3 layers, are piled up according to a predetermined gradient, and rolling is repeated to finish at a predetermined pitch.

Further, in the present invention, in order to prevent slippage between the reinforcing portion of the lower reinforcing material and the laying portion of the upper reinforcing material,
After stacking the slope forming material, lift the end of the laid reinforcing material, and the part of the reinforcing material where the slope forming material is not loaded and the lower reinforcing material winding part that is placed almost horizontally. It is possible to adopt a structure in which the embankment material is inserted and filled in the space formed in the space having a triangular shape in cross section, whereby the reinforcing material can be firmly fixed without using a joint material or the like.

In this case, the length of the portion to be lifted reinforcing member is a portion excluding the contact portion between the slope molding material from director laying of L _1, when it is too long, the consumption of material is large, uneconomical Not only is it difficult to lift,
On the other hand, if the length is too short, the effect of fixing the reinforcing material by the embankment becomes small. Usually, 1 to 1.5 m is suitable. In addition, it is appropriate that the reinforcing material be lifted at an angle of about 5 to 10 degrees with respect to the reinforcing material immediately below. If it is smaller than this, the fixing effect of the reinforcing material by the embankment is small, and if the angle is large, the reinforcing material is reinforced. This is not preferable because the material contacts the upper layer.

The length L of the reinforcing material for one step is L = L ₁ + L ₂ + L ₃ (where L ₁ is the length of the laying portion, L ₂ is the length of the slope surface, and L ₃ is the length of the reinforcing portion). In laying the reinforcing material, the reinforcing material is cut into a length L and prepared in accordance with the design standard set by each length described above. Usually, the length L _{1 of the} laid portion is preferably 1.5 m or more. The reinforcing portion is 100% or more, preferably 200% or more of the length of the laid portion.

In the present invention, the lifting of the reinforcement is to avoid contact between the reinforcements and is therefore necessary in the second and higher stages.

In the construction of the embankment according to the present invention, a foundation laying material, a drainage material, or the like may be laid at the base of the embankment, if necessary.

An example of the embankment construction method according to the present invention will be described below with reference to FIG.

(1) High density polyethylene lattice-shaped civil reinforcement material (manufactured by Nippon Tencer Co., Ltd.) cut into a length L obtained by adding the length L _{1 of the} laying portion L _{2 of the} slope portion L ₃ according to the design criteria Product name tensor) 1 is prepared.

(2) A foundation laying material or drainage material 6 is laid at the base of the embankment.

(3) A reinforcing material is provided on the outer side of the slope line 7, the length L _{3 of the} reinforcing portion,
And the slope length L ₂ part are left, and the laying part length L ₁ is set inside
Lay 1.5m and lay the planned first stage.

(4) A sandbag 2 as a slope forming material is piled up along the slope bottom line 7 with a predetermined gradient in four steps, and then the embankment material 3 is sprinkled out, and the compacting of the slope forming material and the embankment material is repeated. Finish to the design pitch.

(5) The reinforcing material left outside the slope line is wound back along the slope, and the embankment slope formed by rolling is rolled up to cover the upper surface of the embankment. The length of the reinforcement part of the reinforcement material covering the embankment was 3.5 m.

(6) A tensioning jig is attached to the end of the laid reinforcing material, and tension is applied by a machine or instrument to properly shape the slope to the design conditions.

(7) Place embankment material with a thickness of 20-30 cm over a range of 100 cm or more on the laid reinforcement material, avoiding the place where it will be laid next to it and the place where the reinforcement material will be wound in the next stage.

(8) The reinforcing material is tensioned again, the reinforcing material on the slope is brought into close contact with the slope, and the construction of the first stage construction planned portion is completed.

(9) Next, the first shoulder line is the second shoulder line,
After expanding and laying the reinforcing material, the slope forming material is piled up by the same method as the above-mentioned item 3.

(10) Then, when using the sandbag as the slope forming material along the shoulder line 10 to spread the embankment material for the first time, lift up the end of the reinforcement laying portion 1A of the second step The embankment material 9 is sandwiched between the reinforcing material rewinding portion 1C and the winding reinforcing material is securely fixed. After that, the rolling compaction is withdrawn to finish the design pitch and the second stage construction is completed.

(11) After that, the steps (9) to (10) are sequentially repeated and piled up to construct a multi-stage steep embankment.

[Effects of the Invention] When a steep slope embankment is constructed by the method of the present invention, unlike the conventional method, the reinforcing material at each step does not restrain the direction and position. Since the upper part is not constrained by the direction and position of the lower part, for example, when forming a sloped arc wall, it is possible to reduce the number and move the position to any number according to each upper part, so with the conventional method The inherent width of the reinforcing material and material loss for cutting the joint member are eliminated. In addition, it becomes possible to deal with the temporary increase of the area toward the upper part when bending within the gradient, etc.
It is possible to solve the problems in the conventional method.

In addition, since it is possible to use an effective method that could not be done with conventional methods such as so-called brick laying method that shifts the vertical line of each step by half width, the range of use of steep embankment construction method with reinforcement such as geotextile Can be greatly expanded.

[Brief description of drawings]

FIG. 1 is a standard sectional view of a conventional method, and FIG. 2 is a sectional view of an embankment constructed by the method of the present invention. Fig. 1 1 Reinforcing material 1a Laying part 1b Slope 1c Rewinding part 2 Slope forming material 3 …… Embankment 4 …… Joint, 5 …… Temporary retaining pile, 6 …… Drainage Material, 7 …… Hosekiri line, 8 …… Shoulder line 9 …… Filling material 10 …… Shoulder line Fig. 1A …… Laying section 1B …… Slope section 1C …… Reinforcing section

Claims (1)

[Claims] 1. A compacted embankment and an embankment are applied to the expanded and laid civil reinforcement material, and the reinforcement material is rewound along the slope and the embankment upper surface, and the molded embankment upper surface is reinforced. In the method of covering and building a one-step embankment and repeating this operation in sequence to construct a multi-step steep slope embankment, the reinforcement length of the reinforcing material that covers and reinforces the upper surface of the embankment is set to the laying length of the reinforcement material. On the other hand, at least 100% or more, and at the time of embankment construction after the second step, after loading the sloped material on the sill of the reinforcing material, lift the end of the sill to raise the A method for constructing a steep slope embankment characterized by inserting and filling embankment material between the reinforcement part and then rolling and spreading the slope molding material and embankment material.