Earth Support Company (M) Sdn Bhd (ESC) was established in 1994 (and forms the manufacturing arm of the ESC Group) in Malaysia by a group of engineers and contractors who realised that there were major drawbacks with the sheet pile products and service available at the time. By combining experience and technical knowledge, they found that most of these problems could be solved, and with this incentive ESC set out to revolutionise the sheet piling industry.

Sheet piles have been commonly used in the construction industry since early last century. They are used in a wide variety of both temporary and permanent building applications, including retaining walls, slope stabilisation, seepage control barriers, river and canal frontages, quays, wharves, sea walls, dock and harbour works, permanent foundations and ground reclamation works.

Since the implementation of the sheet-piling concept, the understanding and knowledge of designing and constructing such structures has increased significantly, both theoretically and practically. The design of the piles themselves has remained relatively unchanged. Therefore while an engineer may have greater insight into the problems faced and the possible solutions, eventually he is forced to curtail his design to match the capabilities of existing available piles.

The ESC sheet pile (ESC PILE ) concept seeks to remove this handicap. Using the experience gained by the construction industry over the last century, ESC have identified and addressed the common problems associated with sheet piles, and designed a new sheet pile that utilises the latest advances in construction and geotechnical science. The ESC sheet-piling concept will provide engineers the power to select a pile that will meet his or her requirements.

ESC sheet piles are the only Malaysian produced sheet piles available in the market today. A proven product that has been successfully used since 1994 in numerous prestigious projects, the ESC sheet pile is a Malaysian product that will revolutionise a traditionally conservative industry.

ESC Projects (M) Sdn. Bhd. (ESC’s construction arm), carried out a project recently in Kuala Lumpur, Malaysia for the Jabatan Kerja Raya, Malaysia (Public Works Department of Malaysia) where ESC sheet piles were used in a permanent situation. This allowed for faster construction time, lower cost and an aesthetically pleasing finished product.

The project was:

PROJEK MENAIKTARAF JALAN DUTA, JALAN KUCHING DAN JALAN-JALAN HUBUNGAN LAIN DI KUALA LUMPUR

ESC’s scope was to provide the design, supply and construction of the complete retaining wall and the associated ground anchors for the sections with greater exposure. The design is based on a permanent sheet pile system that is supported by permanent ground anchors at W4 and permanent cantilever wall system at W8. The objectives of the system were;

The geotechnical analysis will determined the requirements of the sheet pile retaining wall and anchoring system. The parameters determined were;

1) Earth and groundwater pressures
2) Structural forces
3) Settlements and displacements

Standards used in this section are;

BS 8002: Code of practice for earth retaining structures

Wall 4 during sheet pile installation

Wall 4 during anchor installation

Soil parameters were obtained from the borelogs. For wall W4, the results from the Standard Penetration Test indicated that there was a hard impenetrable layer varying from 9.0m to 12.0m from top of the road finished level, where the Very Dense Sand and Hard Silt layers are found. Therefore, the required embedment for 9.0m piles should be achieved with the usage of high frequency vibro hammer and / or hydraulic drop hammer. Different values of f’ were used for wall W8. This is due to the actual soil conditions on site are much higher than the conditions indicated in soil log. The existing slope with the range of 26.5° - 29.1° steepness could actually stand up stably by itself with the existing soil conditions, which means that the soil frictions on site must be sufficiently high. Moreover the available bore log was carried out 3 years ago about 20m away from wall W8.

- An analysis of the entire retaining wall system was carried out using the ReWaRD Retaining Wall software.

In accordance with BS8002, the following considerations were made to the analysis of the retaining wall in order to comply with the limit state design requirements;

- Minimum over excavation of 0.5m
- Minimum surcharge of 10 kPa
- Use of design soil parameters, which are defined as the
representative soil parameters divided by a mobilisation factor (M)
of 1.2 (effective stress design). Table 2.4.1 and 2.4.2 show the values
for the design soil parameters.

Completed Wall 4

Completed wall 4

During all analysis, active water tables were set conservatively at 1.2m depth on retained side and passive water tables at 0.5m depth on excavated side for wall W4. While wall W8, the active and passive water table were set at 6.0m below the finished road level, since wall W8 is located on top of an embankment.

In accordance with BS 8081 the anchor load design was done in compliance with working load design, therefore the representative soil parameters are used in the analysis of the required anchor loadings.
Due to the different soil conditions required to satisfy the different codes, two cases were analysed of the structure using the ReWaRD software;

Wall 8 before construction

- SP case to determine sheet pile requirements (BS 8002)
- ANC case to determine anchor loadings (Eurocode – Serviceability)

While Wall W8 was analysed using the most critical case (Section on Ch 30.00), with the highest retained soil and steepest slope profile. And the largest factored bending moment recorded was 56.7kNm/m. Please refer to Appendix B for ReWaRD analysis results.

Wall 8 in progress

The retaining wall design will consist of two major components;

- Main Wall Sheet Piles
- Ground Anchor System

Standards used in this Section are;

BS 5950: Code of practice for structural use of steelwork in building

BS 8002: Code of practice for Earth retaining Structures

BS 8081: Code of practice for Ground Anchorages

BS 449: Specification for the use of structural steel in building

Completed construction Wall 8

The moment capacity of the Main Wall is based on;
Mc = fy* Z
Where;
Mc = ultimate design moment capacity
Z = section modulus
fy = material yield strength
= 180 N/mm2 for permanent piles

The ground anchors to be used are 400kN working load capacity anchors.

The preliminary designs for wall W4 were carried out based on the following sequences of works:-
i. Installation of the sheet piles.
ii. Backfill to the ground anchorage level at the back of sheet pile wall.
iii, Installation of ground anchors and RC waler
iv. Backfill to the finished road level
v. Construction of the capping beam.

And the preliminary designs for wall W8 were carried out based on the following sequences of works:-

i. Installation of the sheet piles.
ii. Backfill at the back of sheet pile wall up to the finished road level.
iii. Construction of the capping beam.

ESC Projects ( M) Sdn. Bhd provides the Client with complete solutions to their retaining wall needs. The experience gained in the last 10 years have allowed the company to provide basement, marine, retaining and many other sheet pile solutions to markets in Malaysia and overseas.

For all your sheet pilling solutions, please contact us at :
escprojects@escpile.com

and feel free to view our website at :
http:// www.escpile.com

“ We T a k e T h e P r e s s u r e , S o Y o u D o n ’ t H a v e T o “