JPH0431505A - Construction method of concrete filled continuous wall - Google Patents

Abstract

PURPOSE:To promote work efficiency by continuously driving steel sheet piles so that vertical connections of unit steel sheet piles adjacent to each other in the horizontal direction are respectively separated at a stress resisting interval, and placing concrete in internal hollows of them after erecting a continuous driving body. CONSTITUTION:Preceding box type steel sheet piles 20c and succeeding box type steel sheet piles 20d are connected in a state of load resisting connection with internal and external connection plates 24, 23 and bolts 25 at vertical connections 18. While, preceding box type steel sheet piles 20r and succeeding box type steel sheet piles 20s adjacent to each other in the horizontal direction are also connected in a state of load resisting connection at vertical connections 19. In that case, the box type steel sheet piles are so continuously driven that the vertical connections 18 and 19 are respectively separated by a stress resisting interval. Concrete is placed into internal harrows of a steel sheet pile continuous driving body after erecting the steel sheet pile continuous driving body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for constructing a concrete-filled continuous wall used for structures such as earth retaining, foundations, underground walls, wells, and cells in the civil engineering and architectural fields.

[Conventional technology]

As is well known, there are many types of steel sheet piles, but the method for constructing concrete-filled continuous walls includes H-shaped steel sheet piles 2 and 11 having #1 male and female fitting joints I, as shown in Figure 10.
As shown in the figure, a square steel pipe 14 having a detuning pipe fitting 3 having a fitting slit and fitting with the H-shaped steel sheet pile 2, and a square steel pipe having male and female fitting fittings 5 that are the same as shown in Fig. 12. Box-shaped steel sheet piles such as square steel pipe sheet piles 8 which are equipped with sheet piles 6 and detuned pipe joints 7 having fitting slits as shown in FIG. 13 and fit with the square steel pipe sheet piles 6 are used. , has high mechanical strength, excellent workability, allows for safe construction work, and smooth concrete pouring, so it has come to be used extensively in large-scale construction projects in recent years. .

Therefore, in order to construct a concrete-filled continuous wall using the box-type steel sheet piles, unit steel sheet piles are interlocked and cast to form a continuous steel sheet pile body, and the inner cavity of the continuous steel sheet pile body is After excavating the soil, concrete is poured into the cavity, or as shown in FIG. By repeating the method of erecting the steel sheet pile continuous body 11, which has been separately assembled to a predetermined size, into the excavation groove 10 using the crane truck 12, a desired box-shaped steel sheet pile continuous body with a desired lateral length is obtained. After construction, either concrete is poured into the inner cavity of the steel sheet pile structure, or concrete is poured between the inner cavity of the steel sheet pile structure and between the steel sheet pile structure and the excavation trench wall. Alternatively, a muddy water solidification method is generally employed in which a solidifying agent is introduced into the muddy water in the excavated trench 10 and the muddy water is solidified.

[Problem to be solved by the invention]

Now, the length of the box-type steel sheet piles is limited due to production technology, transportation, and erection conditions, so in applications that require a long erection depth, the connecting parts of the unit steel sheet piles must have the desired strength. It is necessary to connect by means such as welding or bolting to make the connection.

Now, the above-mentioned welding connection is expensive because the dimensions of the unit box-type steel sheet pile are large and high quality welding technology is required, and the cost of equipment such as welding equipment and jigs increases, and the cost is also high due to on-site welding. However, with the addition of environmental and weather issues, there is an unavoidable increase in construction costs.

Furthermore, bolted connections require many through-holes to be drilled in advance at the connecting points of the unit box-type steel sheet piles, require the preparation of many connection plates and bolts, and require a large amount of labor to tighten the bolts. The problem is that construction costs are high because of the need for

That is, FIG. 15 is a schematic cross-sectional view of the conventional bolt connection part of the H-type steel sheet pile 2, and FIG. 16 is a partial schematic side view of the vertical connection part of the H-type steel sheet pile 2. , a predetermined number of through holes (not shown) are usually bored in the flange 2a, and the outer connecting plate 13. Inner connection plate 14. Clamping the flange 2a with the bolts 15, the preceding H-shaped steel sheet pile 20a
and the trailing H-shaped steel arrow W20b.

Further, FIG. 17 is a schematic cross-sectional view of a conventional bolt connection part of the square steel pipe sheet pile 6, and FIG. 18 is a partial schematic side view of the vertical connection part of the square steel pipe sheet pile 6. A predetermined number of through holes (not shown) are bored in the flange 6a in exactly the same manner as in the outer connecting plate 16. Inner connection plate 17. The flange 6a is held between the bolts 15 and the leading square steel pipe sheet pile 6 is
0a and the trailing square steel pipe sheet pile 60b are connected.

In this way, in the concrete-filled continuous wall construction method using box-type steel sheet piles as reinforcement, in order to connect unit steel sheet piles, as explained in detail in Figures 15 to 18, the bolt connection method requires This requires a large number of holes to be drilled and the preparation of a large number of connecting plates and bolts, which requires a large amount of manpower for the connection work, and the welding connection method also requires high connection work costs as mentioned above. As a result, the cost of constructing concrete-filled continuous walls increased and the construction period became longer.

The conventional means of connecting unit steel sheet piles as described above is because it has been considered an essential condition for steel sheet piles that the connecting parts have sufficient strength to withstand the bending and shearing forces received from the ground. For this purpose, careful connections were considered unavoidable, and expensive construction costs were incurred.

The present inventors discovered that in the construction of steel sheet piles as reinforcing materials, which are a major step in the construction of concrete-filled continuous walls, conventional steel sheet pile connections are extremely complex, costly, and take a long construction period. As a result of basically researching the connection of steel sheet piles, we have invented the method of the present invention, which allows for economical connection of steel sheet piles without worrying about strength and with a significantly short construction period.

The purpose of the present invention is to simplify the connection between the unit box-type steel sheet piles in a concrete-filled continuous wall construction method, improve work efficiency, and enable economical construction, as well as improve the mechanical performance of the constructed continuous wall. The objective is to provide a method with extremely high strength and reliability.

[Means to solve the problem]

In order to achieve the above object, the method for constructing a continuous concrete-filled wall of the present invention includes the following steps:
The vertical connecting portions of the unit steel sheet piles of the box type steel sheet piles are load-bearing connections, and the steel sheet piles are connected in a row so that the vertical connecting portions of horizontally adjacent unit steel sheet piles are spaced apart from each other by stress-resistant intervals, and After the steel sheet pile structure is erected, concrete is poured into the inner cavity of the steel sheet pile structure.

[For production]

In a concrete-filled continuous wall construction method using box-type steel sheet piles as reinforcements, the vertical connections between the unit steel sheet piles of the box-type steel sheet piles are simple load-bearing connections that can only support the weight of the preceding steel sheet piles. Therefore, in addition to the number of holes to be drilled, the number of connection plates and bolts required for the bolt connection method is 20 to 30% less than that of conventional connections, and the number of manpower required for connection is 172 to 1/3 that of conventional connections. It can be made to 4.

Further, the steel sheet piles are arranged in a row so that the vertical connection parts of the unit steel sheet piles that are adjacent in the horizontal direction are spaced apart from each other by a stress-resistant distance,
After the steel sheet pile structure is erected, by pouring concrete into the continuous body cavity, the bending moment and shear force generated at the vertical connection part can be absorbed by the concrete filled in the continuous body cavity. Since the shearing force can be sufficiently counteracted, there is no need to worry about mechanical strength.

〔Example〕

Hereinafter, the method of the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a schematic side view of a concrete-filled continuous wall constructed by the method of the present invention, and FIG. 2 is a schematic plan view thereof.

Now, the unit steel sheet pile, that is, the preceding box type steel sheet pile 20c
and the trailing box-type steel sheet pile 20d are the vertical connection portion 1
8, unit steel sheet piles 2 that are load-bearingly connected and adjacent in the lateral direction, that is, leading box-type steel sheet piles 2, as will be described in detail later.
0r and the trailing box type steel sheet pile 20s are vertical connection parts 1
Similarly, load-bearing connections are made at 9.

Thus, each of the vertical connections 18 and 1
As will be described later in detail, the box-shaped steel sheet piles are arranged in a row so as to be spaced apart from each other by a stress-resistant interval.

In FIG. 2, reference numeral 21 indicates a box-type steel sheet pile structure as a reinforcing material, and reference numeral 22 indicates concrete poured into the inner cavity of the continuous structure 21.

Next, FIG. 3 is a schematic cross-sectional view of the bolted joint portion of the H-type steel sheet pile 2 according to the present invention, and FIG. 4 is a schematic sectional view of the H-type steel sheet pile 2.
FIG. 3 is a partial schematic side view of the vertical connecting portion 18 of the FIG.

Now, as shown in the figure, the outer connecting plate 23. Inside connection Fi
24. The leading H type steel sheet pile 20c and the trailing H are connected by bolts 25.
In the present invention, the outer connecting plate 23. is connected to the shaped steel sheet pile 20d. The strength of the inner connecting plate 24 and bolts 25 is designed to be strong enough to support the weight of the preceding H-shaped steel sheet pile 20c.

However, if another preceding H-shaped steel sheet pile is suspended from the lower end of the preceding H-shaped steel sheet pile 20c, it goes without saying that its weight must be increased.

The conventional method required a sturdy connection as explained in FIGS. 15 to 18 to sufficiently withstand the bending and shearing forces caused by the ground as described above, but in the present invention, the dimensions of the connecting plate are also small. , the number of bolts can be significantly reduced.

Therefore, as is clear from comparing the example of FIG. 3 and the conventional example of FIG. 15, even if only the number of bolts is compared, the present invention has a
This means that the amount of through-hole drilling required is only 1/4, and it is clear that the difference in processing and construction costs between the present invention and the conventional method is extremely large.

Next, FIG. 5 is a schematic cross-sectional view of the bolted joint portion of the square steel pipe sheet pile 6 according to the present invention, and FIG. 6 is a partial schematic side view of the vertical connection portion of the square steel pipe sheet pile 6. Just like the H-type steel sheet pile 2, the outer connecting plate 26. Inner connection plate 27
．． A situation is shown in which the leading square steel pipe sheet pile 60c and the trailing square steel pipe sheet pile 60d are connected at the vertical connection portion 29 by bolts 28. In this case, as in the case of the H-shaped steel sheet pile 2, the number of bolts and the through-hole drilling process are compared.
In the present invention, only 174 of the conventional example is sufficient, and the cost difference is extremely large.

However, in the present invention, the connection between the leading and trailing box-type steel sheet piles is not limited to the bolt connection, but as long as the connection between the leading and trailing box-type steel sheet piles can be suspended and withstand the load, it is better to use a small number of connecting plates and bolts, or by welding. For connections, spot welding at a few points is sufficient to withstand the load. Other such simple connections include a method of welding mutual steel sheet piles using steel sheets, and a method of gluing them together using a connecting plate. Define.

Next, FIG. 7 is a partial schematic perspective view for explaining the stress-resistant spacing in the present invention. The figure shows a case in which the unit steel sheet piles 20
The illustration is based on the assumption that a bending force is applied to e and the unit steel sheet pile 20e comes off at the vertical connection portion 30.31.

However, in FIG. 7, filling concrete is not shown for convenience of explanation.

Figure 8 is a stress diagram regarding the shear strength P per unit length on the shear plane (two planes), and the shear strength P is as follows (1
) as shown in the formula.

P=τcr x h ・−
−−・−(1) However, τer: Out-of-plane shear strength of concrete per 1 cd (-3.0 kg/d for boat fishing
) h: Web height (1) Therefore, the torsional shear strength Tc of concrete can be determined by the following equation (2).

Tc, = P − Lt/6 −・−・・(2
) Figure 9 is a graph showing the relationship between the stress-resistant interval and the torsional shear strength T e r of the concrete for a unit steel sheet pile with a web height h of 400 m++, and the horizontal axis is the stress-resistant interval L ( m), the vertical axis indicates the torsional shear strength 'rc, (t-m) of the concrete.

Now, in this way, the unit steel sheet piles 20e that are adjacent in the horizontal direction,
20f of vertical connecting portions 30.31 are arranged in series so as to be separated by a stress-resistant interval . ．． The bending moment and shearing force generated in the steel sheet piles 31 can be sufficiently counteracted by the shearing force T- of the concrete filled in the interior of the steel sheet pile connected body.

In other words, the stress resistance intervals may be set in the range of bending strength M of steel sheet piles, <torsion shear strength Tcr of concrete, shear strength Ssr of steel sheet piles, <pushing shear strength of concrete.

In other words, the stress-resistant spacing is determined by the yield strength of the main body of the steel sheet pile and the shear strength of the concrete, so the stress-resistant spacing is appropriately designed depending on the type and dimensions of the selected steel sheet pile and concrete.

However, since the H-type steel sheet pile 2 and the square steel pipe sheet pile 6 use straight steel sheet pile joints as joints, the joint efficiency can be up to 50%, so there is a high degree of freedom in setting stress-resistant intervals. There are advantages.

The inventors have a cross-sectional dimension of 400 x 400 mm and a length of 6.
Using H-type steel sheet piles of 000 to 16,000, depth 45
In constructing a closed continuous underground wall of ,000 m, the vertical connection between the unit steel sheet piles was made a load-bearing connection using bolts, and the stress-resistant interval was then set to 3,000 m to form a continuous body. Later, it was filled with blast furnace cement concrete to achieve the desired purpose.

〔Effect of the invention〕

Since this invention is configured as described above, it produces the effects described below.

Since it is possible to extremely simplify the connection of unit box-type steel sheet piles as reinforcing materials, work efficiency is high, and it not only makes it possible to construct concrete-filled continuous walls in a short period of time and economically. The mechanical strength and reliability of the constructed continuous wall are extremely high, and its practical effects in the civil engineering and architectural fields are extremely large.

[Brief explanation of drawings]

Fig. 1 is a schematic side view of a concrete-filled continuous wall constructed by the method of the present invention, Fig. 2 is a schematic plan view thereof, and Fig. 3 is a schematic sectional view of the bolted joint part of the H-shaped steel sheet pile used in the present invention. Fig. 4 is a schematic side view thereof, Fig. 5 is a schematic sectional view of the bolted joint part of the square steel pipe sheet pile used in the present invention, Fig. 6 is a schematic side view thereof, and Fig. 7 is the stress-resistant interval in the present invention. Partial schematic perspective view for explanation,
FIG. 8 is a stress diagram regarding the shear strength P, and FIG. 9 is a stress diagram showing the stress interval and the torsional shear strength T of the concrete. Figures 10 to 13 are schematic cross-sectional views of different box-type steel sheet piles, Figure 14 is an explanatory diagram showing the situation in which steel sheet piles □ are erected using the muddy water excavation method,
Fig. 15 is a schematic sectional view showing the bolted joint part of a conventional H-shaped steel sheet pile, Fig. 16 is a schematic side view thereof, Fig. 17 is a schematic sectional view showing the bolted joint part of a conventional square steel pipe sheet pile,
FIG. 8 is a schematic side view thereof. 1... Fitting joint, 2... H type steel sheet pile, 2a... Flange, 3... Detuned pipe joint, 4... H type steel sheet pile, 5
... Fitting joint, 6... Square steel pipe sheet pile, 6a... Flange, 7... Detuning pipe joint, 8... Square steel pipe sheet pile, 9.
... Ground, 10 ... Excavation groove, II ... Steel sheet pile connected body, 12 ... Crane truck, 13 ... Outside connection plate, 14
...Inner connection plate, 15...Bolt, 16...Outer connection plate, 17...Inner connection plate, 18...Vertical connection part, 19...Vertical connection part, 20a...・ Trailing H
Type steel sheet pile, 20b... Leading H type steel sheet pile, 20c...
Leading box type steel sheet pile (H type steel sheet pile), 20d... Trailing box type steel sheet pile (H type steel sheet pile), 20r... Leading box type steel sheet pile, 20s... Trailing box type steel sheet pile, 21... Box type steel Sheet pile long throw body, 22... Concrete, 23... Foreign connection plate, 24... Inner connection plate, 25... Bolt, 26... Outer connection plate, 27.
...Inner connection plate, 28...Bolt, 29...Vertical direction connection part, 30...Vertical direction connection part, 31...Vertical direction connection part, 60a... Leading square steel pipe sheet pile, 60b.・
- Trailing square steel pipe sheet pile, 60c... Leading square steel pipe sheet pile, 60
d... Trailing square steel pipe sheet pile. 2 (20C) 2 (20d) 2 (20c 20d) Fig. 5 6 (60c, 60d) Fig. 6 Tcr (t-m) L (m) Fig. 10/ 2-/ Fig. 11 Fig. 15 Fig. 2 ( 20a, 20b) Fig. 16 2 (20a) Fig. 17 6 (60a 60b)

Claims (1)

[Claims] In a concrete-filled continuous wall construction method using box-type steel sheet piles as reinforcing materials, the vertical connections between the unit steel sheet piles of the box-type steel sheet piles are load-bearing connections, and the vertical connection between the horizontally adjacent unit steel sheet piles A method for constructing a concrete-filled continuous wall, which comprises: installing steel sheet piles in a row so that the connecting parts are spaced apart from each other by stress-resistant distances; and, after the steel sheet piles are erected, concrete is poured into the inner cavity of the steel sheet piles.