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International Journal of Scientific Research and Innovative Technology ISSN: 2313-3759 Vol. 4 No. 3; March 2017
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Design of Anchored-Strengthened Sheet Pile Wall: A Case Study
Ümit Gökkuş*1, Yeşim Tuskan2
1Prof.Dr., Department of Civil Engineering, Celal Bayar University, İzmir, Turkey
(E-mail: umit.gokkus@cbu.edu.tr Phone: 90(236)2012303) 2Res.Asst., Department of Civil Engineering, Celal Bayar University, İzmir, Turkey
(E-mail: yesim.tuskan@cbu.edu.tr Phone: 90(236)2012328)
*Corresponding Address: Dept.of Civil Eng, Celal Bayar University, Sehit Prof.Dr.Ilhan Varank Campus,
450140,Yunusemre-Manisa/TURKEY
Abstract: The design of a 27.83 m high anchored-strengthened steel sheet pile, effective on building
foundations, staged excavations and earth retention, is presented in this study. Sheet piling with a single
anchor was considered. Wall deformations, bending moments, wall shear forces and anchor forces were
investigated for the conditions studied. An evolution of the safety provided by classical limit equilibrium
method for anchored sheet pile wall is investigated. Investigation of the stabilization problems that are
mentioned above was observed with the determination of the design parameters such as anchors, box pile wall
profile and interaction of these parameters which effects the deformations into the ground during the
stabilization studies. Moments of inertia were gradually changed and strengthened parts of profile were
placed considering shelves.
Keywords: Sheet Pile Wall, Anchorage of Sheet Pile Wall, Strengthened Sheet Pile Profile,
Structural Analysis of Retaining Walls
1. Introduction
Brinch-Hansen (1953) developed a design method with plastic hinges for sheet pile wall and ever since this
method has formed the basis for the current Danish design practice (Brinch et al.1953). Retaining walls are
used to maintain a difference in the elevation of the ground surface. The retaining wall can be classified as
rigid or flexible walls according to system rigidity. A wall is considered to be rigid if it moves as a unit in
rigid body and does not experience bending deformations like most of gravity walls. However, flexible walls
are the retaining walls that undergo bending deformations in addition to rigid body motion. Steel sheet pile
wall is the most common example of the flexible walls because it can tolerate relatively large deformations. A
continuously interlocked pile segments embedded in soils were used to resist horizontal pressures. Steel is the
most common material used for sheet pile walls due to its resistance to high driving stresses, relatively
lightweight, and long service life (Bowles 1988).
In recent years, Choudhury et al.(2006) presented a paper concerning with the lateral earth pressure on sheet
pile against earthquake motion. Soils with high groundwater tables or soils with low bearing capacity are ideal
sites for the application of sheet piling (Tan et al. 2008). The anchored sheet pile walls used as either
permanent or temporary lateral earth support system in various civil engineering projects are one of the most
reliable methods of structure protection (Bilgin et al.2009). They proposed the response of a sheet pile
retaining wall with a single anchor to improve the sloping ground conditions. The advantage of decreasing the
cut and fill operations of slope was presented for a 12 m high slope. After that, Ramsden et al (2010)
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investigated the load carrying capacity of the sheet pile wall by examining the lateral wall deflection and
examined the cross-section lost due to the corrosion. The rehabilitation of an 11 m high offshore sheet pile
wall is studied (Ramsden et al.2010). Zhang et al. (2011) studied the feasibility of concrete sheet pile retaining
wall as vertical shoring. Finite element analysis was carried out to define earth pressure, settlement, and
horizontal displacement of shoring structure and the pile’s stress and strain variation by simulating the design
conditions (Zhang et al.2011).
Within last five years, Isobe et all.(2014) used the sheet pile wall made of steel pipes to reinforce the caisson
foundation in their studies. Armanyous et al.,(2016) studied experimentally in double sheet-walls replaced
intervally. Gazetas et al. (2016) also worked especially for tall and anchored sheet-pile wall under seismic
loads as mentioned in Choudhury et al.(2006). They studied on wall composed of I and V shaped sheet piles.
In this study, it is aimed that tall and anchored sheet pile wall are strengthened by using sheet piles varying
sections from the bottom to top of wall. On a case study considering this strengthened sheet pile, the
calculation procedures taking into account the uniform surcharge loads and lateral earth pressure stated
clearly.
2. Methodology
The wall movement from active earth pressure towards the passive conducted the horizontal pressure
distributions around the sheet pile wall. The simple triangular pressure distribution is adopted for an ideal
conservative solution with lower earth pressures and smaller bending moments in the wall.
For the effectiveness of the anchorage system location, outside of the potential active failure zone must be
selected behind a sheet pile wall. The anchorage system length is designed to provide sufficient resistance to
movement under limit state conditions. The slip circle of overall stability is also considered for the length of
the tie rod system. Steel sheet piles are used in many aggressive environments and consequently corrosion
protection or factor influencing effective life must be considered. There are several design methods for sheet
pile walls. The simplified method is slightly more conservative than the full method and gradual method with
the benefit of simplicity on the traditional system of equations (Padfield et al.1984). The main advantage of an
anchored sheet pile wall, against those cantilevered, is the ability to reduce the embedment depth by increasing
the excavation depth. Initially the total pressure coefficients for active and passive conditions were calculated
in presence of earthquake magnitude by the following equations:
��� = ��±��� ��������� ��� ����������� �1 + �����������������
���������������� �!
(1)
�"� = ��±��� ��������� ��� ����������� �1 + �����������������
���������������� �!
(2)
For retaining structures restrained by anchors equivalent horizontal seismic coefficient and vertical seismic
coefficient were presented in the equations:
#$ = 0.3�( + 1)* (3)
#+ = 2#$ 3⁄ (4)
Effective ground acceleration coefficient, A0, was selected 0.4 for seismic zone 1 in Turkey, building
importance factor, I, was selected 1.00 for the standard buildings.
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3. Case Study
A wall is built to support a retained height of 16 m with the ties acting at 3.8m below ground level. The
simplified method for a fixed earth analysis assumes that the point of contra-flexure in bending moment
diagram occurs at the level where the active pressure equals the passive pressure.
The length of sheet pile is found by moments about the 1.67 m below the low ground level and forces
equilibrium. Then the depth below the point of contra-flexure is increased by 20% to give the pile penetration.
Zero shear occurs at 3.8 m and 13.87 m below the ground level. The backfill behind the sheet pile wall has a
dry unit weight of about 18 kN/m3, a saturated unit weight of 20 kN/m3 and shear strength parameter of φ =
40˚. Additional features, such as the ground water height Hw and surcharge load q are shown in Figure 1 as a
typical cross-section with the maximum design wall height. A surcharge load of 17 kN/m2 was applied for
traffic loading.
The total active and passive pressure coefficients were summarized in Table 1. for saturated and natural unit
weight conditions with ground water level (Kip et al.1999). The calculated horizontal pressures and the
calculated values of horizontal equivalent forces were depicted in Figure 2. The distance between the contra
flexure point and the dredged level with the pressure value of point, Pc2 are calculated by the following
equations:
.�! = �/ + 012� + 0 ′2!��′ (5)
3 = 45�6′�78′ �79′ (6)
Bending moments about the point B were calculated and D1 was founded by the moment equilibrium then the
forces equilibrium was carried out to obtain the anchor load, T. Section PSp 1117 with height of 1117 mm and
width of 460 mm second moment of inertia Ix=2505150 cm4, section modulus ωx=44860 cm3,allowable stress
= 23.44 kN/cm2 were selected according to ASTM A328 was selected in the Sheet Piling Handbook (2010)
and the section is shown in Figure 3. The total deflection exhibited by a retaining wall comprises a component
based on the deflection of the section as a result of the applied loads and a component based on compression
of the soil as the active/passive pressure regime is established. The calculations of shear forces and bending
moments are set out in Figure 4. with the parametric study of SAP2000 and were compared with the results
obtained by effective stress distribution. The ability of large size construction is carried out with
reinforcement. An anchored-strengthened sheet pile wall cross-section is shown in Fig.5.
It is possible to enhance the strength of overlap parts for different layers. Joints of sheet pile wall were
strengthened in presence of suitable overlap length. Piling energy of sheet pile wall should be increased for
additional profiles. The strengthened parts may also be located on beam flanges of sheet pile wall.
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4. Conclusion
In this study, efforts were made to develop an anchored sheet pile wall system to satisfy successfully external
and internal stability of the retaining wall. Results show that the proposed method can capture the
displacements and bending moments of retaining wall for quite deep excavations. Deep-seated Failure and
rotational failure due to inadequate pile penetration were prevented to improve soil stability. The designed
sheet-pile wall with anchor system enabled the stability to carry out earth and foundation work safely.
References
Armanyous,A.M., Ghoraba,S.M., Rashwan,I.M.H., Dapaon,M.A.,(2016) A Study on Control of Contaminant
Transport through the Soil Using Equal Double Sheet Piles, Ain Shams Engineering Journal, Vol:7,
pp.21–29
Bilgin, O. and Erten, B. (2009). Anchored Sheet Pile Walls Constructed on Sloping Ground, International
Foundation Congress and Equipment Expo. 145-152.
Bowles, J. E. (1988). Foundation Analysis and Design. 4th Ed., McGraw-Hill, New York.
Brinch Hansen, J., (1953). Earth pressure calculation, PhD Thesis, University of
Cophenagen.
Choudhury,D., Chatterjee,S.,(2006), Dynamic Active Earth Pressure on Retaining Structures, Sadhana, Vol.
31, Part 6, pp.721–730
Gazetas,G., Garini,E., Zafeirakos,A.,(2016), Seismic analysis of tall anchored sheet-pile walls, Soil Dynamics
and Earthquake Engineering, Vol:91, pp.209-221
Isobe,K.,Kimura,M.,Ohtsuka,S.,(2014),Design Approach to a Method for Reinforcing Existing Caisson
Foundation Using Steel Pipe Sheet Piles, Soils and Foundations, The Japanese Geotechnical Society, Vol:
54 (2), pp.141–154,
Kip, F. and Kumbasar, V. (1999). Problems in Soil Mechanics, Caglayan Publishing, Istanbul (in Turkish)
Padfield, C. J. and Mair, R. J. (1984). Design of retaining walls embedded in stiff clay, CIRIA Report 104.
Ramsden, M.R., Griffiths, T.F., (2010). Steel Sheet Pile Wall Wale Rehabilitation, Ports, pp.193-202.
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Systems,GDP-11,Revision #4, Geotechnical Bureau, Department of Transportation, NY
Sheet Piling Handbook (2010), 3rd Edition, Hoesch Spundwand und Profil-A Member of the Salzgitter Group
and Peiner Trager-A Member of the Salzgitter Group, ThyssenKrupp GfT Bautechnik
Tan, Y. and Paikowsky S. G. (2008). Performance of sheet pile wall in peat, Journal of Geotechnical and
Geoenvironmental Engineering, Vol 134, No.4, 445-458.
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Figures
Fig. 1 Anchored sheet pile wall
Fig. 2 (a)Horizontal effective stress distribution (b) Horizontal equivalent forces with tie rod force
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Fig. 4 Shear Force
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Fig.3 Sheet Pile Wall Box Section
ear Forces and Bending Moments of the Sheet Pile Wall System
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Fig. 5 Strengthened Cross-Section of Sheet Pile Wall
Table
Table 1 The total active and passive pressure coefficients
Total Pressure Coefficient
Kat,MAX (above water table) 0.283
Kat,MAX (below water table) 0.553
Kpt,MAX (above water table) 8.949
Kpt,MAX (below water table) 6.636