Proceedings of the First International Conference on Press-in Engineering 2018, Kochi

Press-in with Augering; an Installation of Steel Sheet Piles ConnectedLongitudinally (Hard Ground Press-in Method)
Koichi MOMONO
Director, GEOTECH Co., Ltd, Mie, Japan
Email: post@geotech.ecnet.jp

Manabu FUJITA
Representative director, GEOTECH Co., Ltd, Mie, Japan
Email: post@geotech.ecnet.jp

ABSTRACTThe case described here is about the construction of the earth retaining wall in an aseismic reinforcement work of theEnoura Ohashi Bridge in Mie Prefecture, Japan. The site showed the maximum SPT N-value is 88, and a standard pressin was not applicable. In addition, the site was adjacent to residential areas, and a pressing machine that would emit as
low vibration and noise as possible should be selected. Therefore, the press-in assisted with augering was adopted.
The construction site was limited under the existing bridge. Including the hoisting wire of a crane, the assembly length of
the Pile auger for 8.0 m steel sheet piles became 17.88 m. Therefore, an auger hoisting system for the installation under
overhead obstructions was selected at the design stage. However, segmenting the augers, casings and steel sheet piles, thenormal press-in assisted with augering became possible by connecting the spliced piles vertically. When the site wasnarrow that a crane could not be set, the operation was carried out by the Silent Piler F111 (Hereafter, F111) only, without
the crane support. This way, the construction method adopted for this work contributed to making the construction period
shorter as well as saving the cost.
Key words: Press-in Method assisted with augering, Hard Ground Press-in Method, Maximum N-value,
Overhead clearance, Silent Piler

1. OUTLINE OF THE PROJECT

reinforcement with the concrete jacketing method. About

1.1. Location
The project was an aseismic reinforcement work of

6.0 m below the ground surface, there was a sand and gravel

the Enoura Ohashi Bridge in the Nagashima harbour,the hardness of the ground, it was possible to conduct thelocated at Nagashima, Kihokucho, Kitamuro, Mieconstruction by using the three-point-supported type pile

Prefecture, Japan. The site consisted of sand and gravel

driving rig (Hereafter, three-point pile driver rig). However,with the maximum SPT N-value of 88. The site wasthere was an existing bridge girder as an overheadadjacent to residential houses. In addition, the construction

obstruction. In addition, the site was narrow, and a large

had to be carried out at a place where there was anmachine could not be used. After consideration, it wasoverhead clearance of 12.3 m (Fig. 1).

judged and concluded that the construction would belayer with the maximum SPT N-value of 88. Judging frompossible, if the Press-in Method with augering (F111) was
1.2. Background and Objectives of the Project
The construction plan was to press-in 174 no. of 8.0 m

used, since the casing auger could cope with segmentationand connection of the steel sheet piles.

long steel sheet piles of type III in a rectangular shape as atemporaryearthretaining

wallforanaseismic- 453 -Proceedings of the First International Conference on Press-in Engineering 2018, Kochi

2.3. Structural TypeSide viewFig.3 shows a plan view of the temporary structure.

2000

P12B

3300

Ag

13200

DL=-5.000

1087

12463
14400

18800

shape of 16,000 mm x 18,800 mm. In total, 174 steel sheet
piles of type III were pressed-in:
・ 120 no. U-shaped steel sheet piles, type Ⅲ, L=8.0m
・ 27 no. U-shaped steel sheet piles, type Ⅲ,
L=8.0m (4.0mx2), one joint
・ 27 no. U-shaped steel sheet piles, type Ⅲ,

8000

Lining RC
Bridge axial direction t=250mm
Bridge-axial-orthogonal direction t=250mm

Overhead clearance 12300

The steel sheet piles were to be installed in a rectangular

L=8.0m (3.5m+4.5m), one joint

850
2200

Non-joint piles

AsAg

One joint piles
27@400=10800

2000

3200

2300

2200

Fig. 1

Side view of the bridge

Non-joint piles

16000
11400

23009000Initial Press-in

2. STRUCTURAL TYPE AND PILING METHOD
6800

63@400=25200

3300

2.2. Ground Condition

12000

The site was in the vicinity of a river mouth area.

14400
18800

57@400=22800

2.1. Site Condition

As shown in Fig. 2, the site ground consists of sandand gravel layer with occasional boulders. Maximum SPT
2200

N-value was 88 in the sand and gravel layer, about 6 m
below ground surface.

2000

Non-joint piles

Fig. 327@400=10800
One joint piles

3200

Non-joint piles

Layout of the steel sheet piles

2.4. Piling Method
The Press-in Method with augering (Hard Ground
Press-in Method) was adopted (Fig. 4). The construction
was carried out in the following stages:
1) By using a 5.0 m long casing and auger, a lower
spliced steel sheet pile is installed
2) Press-in the spliced steel sheet pile, disconnect themotor from the Pile auger and lay it on the ground3) Connect the motor with a 4.5 m middle auger andcasing and joint them with the already installed
auger and casing after the crane lifts them up.
Fig. 2

Layout of the steel sheet piles- 454 -Proceedings of the First International Conference on Press-in Engineering 2018, Kochi

4) Pitch an upper steel sheet pile and connect it with

3. PRESS-IN PILING

the lower steel sheet pile by welding.
5) Press-in the jointed steel sheet pile, disconnect the3.1. Condition during Pressing-in Steel Sheet Piles
Though the maximum N-value was 88, the groundmotor from the Pile auger and lay it on the ground.

was not as hard as it required pre-augering. Therefore, the6)Connect the motor with a 2.0 m upper auger andPress-in with simultaneous augering, which is “Coringcasing and joint them with the already installedpress-in”, was conducted. The construction was started

auger and casing after the crane lifts them up.

with installing three no. 8 m-long steel sheet piles, then7) Press-in the jointed steel sheet pile.

from the 4th sheet on, the steel sheet piles with a single

8) Complete of the Press-in operation.

joint were pressed-in.

9) Extract the Pile auger including the disassembling

Underneath the bridge, steel sheet piles wereof the augers and casings.

installed using a 4.9ton telescopic boom crawler crane10) Repeat the procedure from 1) to 9)(hereafter, telescopic crane) (Photo 1). In addition, thenumber of supervisors was increased to make sure the toe

Note that the type A piles (L=8.0m/4.0mx2) and theof the crane boom would not touch the bridge girder, andtype B piles(L=8.0m/3.5m+4.5m) are alternately installed.

the construction was carried out cautiously, by restricting
the boom angle and extension/contraction limits of the50ton rough terrain crane (Photo 2).

②③④⑤⑥

⑦⑧

Length of theassembled casing
2000 2130
500
5004500

4500

8000

3500

4500

2000

2000

3500

2000

500

4500
9330

500

Silentpiler F111
4500
4500

12300
1000

12.3m

2970

▼Overhead clearance
Layout of joint sheet piles
TypeⅢ L=8.0m (4.5m＋3.5m)

14130

①4500
500

4500

4000
8000
4000

Fig. 4

Piling procedure of the Press-in Method with augering- 455 -

14130

2000

4000

2000

2000

2000 2130
500

Length of theassembled casing
4500
9330

500
500

4000
4500

12300

Layout of joint sheet piles
TypeⅢ L=8.0m (4.0m＋4.0m)

1000

12.3m

2970

▼Overhead clearanceProceedings of the First International Conference on Press-in Engineering 2018, Kochi

When assembling and disassembling the augers andcasings, the Pile auger should be once laid on the ground.
The 50ton rough terrain crane hoisted the edge of the Pile
auger whilst the 4.9ton telescopic crawler crane hoisted
the other edge of it (Photo 3). When the Pile auger ishoisted after connecting the augers and casings, the same
operation was conducted. There were some level
differences on some narrow places of the ground where
the rough terrain crane could not be set up (Photo 4).
In that case the press-in operation was continued onlyby the F111, and steel sheet piles were supplied by the4.9ton telescopic crane (Photo 1). As the enclosure withclosed corners approached, the inclination of the installed

Photo 3. Mutual hoisting with the 4.9ton telescopic crawler and 50ton

steel sheet piles and the distance between them wererough terrain crane, when the Pile auger is laid on the groundclosely monitored, thus the press-in operation of 174 steel
sheet piles was completed successfully.

Photo 4. For the enclose with closed corner, the piling operation
was being conducted carefully after the installation under the bridge.

Photo 1. Pitching of steel sheet piles using a 4.9ton telescopic

3.2. Productivity
The productivity of the construction is summarizedcrawler crane under a girderin Table 1. As shown in the table, on average steel sheet
piles without connection joints were installed at a rate of
15 piles/day, whereas those with one joint were installed
at a rate of 6 piles/day on average. The press-in operation
was completed in a period of 16 working days. The entire
construction period of the aseismic reinforcement work of
the Enoura Ohashi Bridge was from February 8, 2017 toNovember 30, 2017.

Photo 2.

Planned augers and casings and an increase in thenumber of supervisors enabled the piling operation.

- 456 -Proceedings of the First International Conference on Press-in Engineering 2018, Kochi

Table 1.
Pier "P-12" of theEnoura bridge
Sheet pile,
type Ⅲ, L=8.0m
120 no.
Sheet pile,
type Ⅲ, L=8.0m(2@4.0ｍ), 120 no.
Sheet pile,
type Ⅲ, L=8.0m(3.5m+4.5ｍ), 120 no.
Number ofnon-joint piles

10-Mar

11-Mar

12-Mar13-Mar

14-Mar15-Mar

16-Mar17-Mar18-Mar

19-Mar

Fri.

Sat.

Sun.

Mon.

Tue.

Wed.

Thu.

Fri.

Sat.

Sun.

Carrying inmachineryandmaterials
Carrying insheet piles

NoworkCarrying insheet piles

DayoffNumber ofnon-joint piles

N/A

3no.

5no.

6no.

6no.

7no.

6

11

17

23

30

20-Mar21-Mar22-Mar23-Mar24-Mar25-Mar26-Mar27-Mar28-Mar29-Mar30-Mar

Mon.

Tue.

Wed.

Thu.

Fri.

Sat.

Sun.

Mon.

Tue.

Wed.

Thu.

Cornerinstallation

Piler
Dismantlement
and Carryingout of Piler

Dummy
piles
L=5m,1 no.
Cornerinstallation

AM 9:00
Nondestructiv
einspection

Dummypiles
L=5m,1 no.
Cornerinstallation

Dummypiles
L=5m,1 no.
Cornerinstallation

Color checkCheck byauthority

Day
off

Installation of no joint piles
17no.

Number ofone joint piles
Numbers

N/A

Installation of one joint piles

Setting-upof Piler

Numbers

Sheet pile,
type Ⅲ, L=8.0m
120 no.
Sheet pile,
type Ⅲ, L=8.0m(2@4.0ｍ), 120 no.
Sheet pile,
type Ⅲ, L=8.0m(3.5m+4.5ｍ), 120 no.

Day
off

Installation of no joint piles
3no.

Number of
one joint piles

Pier "P-12" of theEnoura bridge

Productivity

20no.

22no.

Closing at
the corner

Installation of no joint piles

4no.

7no.

Installation of one joint piles

Installation

24no.

Carrying out
construction
materials

23no.
Sitekeeping

47

N/A

N/A

7no.

5no.

7no.

8no.

67

89

100

105

112

127

151

174

Completion

3.3. Encountered Difficulties
In the original design, a construction method using

10.0 m, and that the Hard Ground Press-in Method with

the GIKEN auger hoisting system was planned. It wasspliced steel sheet piles be used for the overhead clearance

however judged that the construction by means of thelarger than 10.0 m.

Hard Ground Press-in Method could be possible byconducting the assembling/disassembling of the augers
and casings. However, had it been possible to conclude
that the Hard Ground Press-in Method could be applied tothe site when the bridge overhead clearance was known tobe 12.3 m, the construction planning would have been
made smoother. For a smooth planning, we feel that a kindof table for the combination of auger and casings should
be organized so that it can be referred to as a guideline forconsidering the construction under overhead obstructions.
The minimum overhead clearance in the construction
method with the GIKEN auger hoisting system is up to 7.0m (applicable for 400mm-wide U-shaped steel sheet piles).

Photo 5.

On the other hand, the minimum overhead clearance in thethe location inside the dashed line, where the ground was narrow

Hard Ground Press-in Method we adopt is 10.0 m.

and possessed differential elevations. Press-in operation wasTherefore, we concluded that the GIKEN auger hoisting

carried out by the F111 only, without the crane support to lift thesystem be used for the overhead clearance smaller thanPile auger.

- 457 -Setting up the 50ton terrain crane could not be set atProceedings of the First International Conference on Press-in Engineering 2018, Kochi

4. CONCLUDING REMARKSIn the Press-in Method assisted by augering (Hard5. ACKNOWLEDGEMENTS
The authors are grateful to everyone that wasGround Press-in Method) using steel sheet piles withcooperative to the project. In particular, we would like tojoints, the ground condition was pretty good as it was ashow our sincere gratitude to Hirano Co. Ltd., for

not-too-hard sand and gravel layer so that the press-inproviding detailed construction materials as well as to Mr.

operation with the F111 could be conducted in quite stable

Jundo Kobayashi for providing the site photos during thecondition. In addition, due to good teamwork andconstruction.

communication among the workers, segmentation andconnection work of the casings and augers was gradually
improved, which helped the work to be done speedily, andREFERENCES
JPA. 2017. Hard Ground Press-in Method. (in Japanese)thus the construction was completed safely andsuccessfully.
In the case of construction with the Press-in Method
assisted by augering, there is no work that can be done
under the same site condition. We came to a conclusionthat we can achieve the best and safest possibleconstruction by having close and in-depth discussions
with the prime contractor day by day under the conditionat each time, and by building good teamwork among theworkers to exchange good ideas and then implement them.
(Photo 6).

Photo 6.

Completion of the aseismic reinforcement work

- 458 -