FIELD OF INVENTION

The present invention relates to an interlock of a sheet pile and more particularly, an interlock of a sheet pile that presented in a form of hook comprises an engaging section which is configured to have a curved surface.

BACKGROUND OF THE INVENTION

A sheet pile wall is a row of interlocking and vertical pile segments that forms earth retaining walls. Sheet piles are mainly used for temporary construction work such as construction of bridge, road work, basement or temporary excavation. Since sheet piles are mainly used for temporary construction work, when sheet piles are being prepared for a construction project, to complete the whole construction project in the most cost-effective way, a construction company would consider the material cost, the ability of the sheet piles to be installed into a ground, the ability of the sheet piles to be extracted from the ground after the construction project has been completed and the reusability of the sheet piles.

An interlock of the sheet pile is the most important functional element to ensure that the sheet pile wall is rigid and stable for installation. During the stage of designing the interlock of the sheet pile, a designer should consider that the performance of the sheet pile has to be tough and tight enough to ensure structural integrity as retaining wall and functionality of controlling water seepage and deflection of wall. There are few well-known types of interlock of sheet pile in the industry and one of the famous designs of interlock of the sheet pile is Larssen-type interlock.

Larssen-type interlock has been accepted for applications in worldwide since long time ago as sheet pile interlock element. However, on-site construction practice has shown that Larssen- type interlock could cause excessive piling force and poor reusability of sheet piles. During the actual piling operation, 30 percent to 50 percent of piling resistance is caused by interlock resistance. This implies that to reduce the piling resistance and to increase the chance of reusing the installed sheet pile, the interlock should be configured in a more appropriate manner. Therefore, it is the objective of present invention to design a highly adapted, reduced piling resistance and reusable Larssen-type interlock element for the sheet pile.

SUMMARY OF THE INVENTION

The present invention relates to an interlock of a sheet pile. According to the present invention, the interlock of the sheet pile is presented in a form of hook. The hook comprises a hook tip followed by an engaging section and a stem. The engaging section together with the hook tip functions as a latching portion of the sheet pile. The stem extends away from the engaging section and connects to a web of the sheet pile. Preferably, the engaging section is configured to have a curved surface.

In the present invention, the engaging section allows up to 15 degrees of rotation of the sheet pile when the interlock is interlockably engaged with a corresponding interlock of another sheet pile. It should be noted that the interlock of present invention is adaptable to different shapes and configurations of sheet piles.

It will be appreciated that the curved surface of the engaging section of the interlock allows the sheet pile to be reused after the construction work has been completed.

The present invention is hereinafter fully described and illustrated in the accompanying description and drawing, it being understood that various changes in the details may be made without departing from the scope of the invention or sacrificing any of the advantages of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be fully understood from the detailed description given herein below and the accompanying drawing which is given by way of illustration only, and thus are not limitative of the present invention, wherein:

Fig. 1 shows the front view of the preferred embodiment of an interlock of sheet pile.

Fig. 2 shows the comparison of present invention and prior art invention in terms of degree of rotation when the interlock of one sheet pile is interlockably engaged with a corresponding interlock of another sheet pile.

Fig. 3 shows the comparison of present invention and prior art invention in terms of free space of adjustment when the interlock of one sheet pile is interlockably engaged with a corresponding interlock of another sheet pile.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An interlock will be described in accordance to the accompanying drawings Fig. 1 to Fig. 3, either individually or combination thereof. Hereinafter, this specification will describe the present invention according to the preferred embodiment of the present invention. However, it is to be understood that limiting the description to the preferred embodiment of the invention is merely to facilitate discussion of the present invention and it is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the scope of the appended claims.

According to the preferred embodiment of the present invention as shown in Fig. 1, the interlock (1) of a sheet pile is presented in a form of hook. The hook comprises a hook tip (2), an engaging section (4) and a stem (6). As shown in Fig. 1, a reference dotted line is indicated on two respective hooks to clearly show the position of the engaging section (4) and the stem (6). In the present invention, the hook tip (2) is followed by the engaging section (4) and the hook tip (2) is bending towards the web of the sheet pile.

Preferably, the engaging section (4) together with the hook tip (2) function as a latching portion between two interlocks (1, 1’) of different sheet piles. The engaging section (4) of the interlock (1) is configured to have a curved surface comparing with the prior art and existing sheet pile to allow higher degree of rotation and greater dimension of adjustment when the interlock (1) is interlockably engaged with a corresponding interlock (G) of another sheet pile that comprises a corresponding hook tip (2’), an engaging section (4’) and a stem (6’). During the pile-driving operation, the piling activity will experience less piling resistance and the sheet pile can be installed into the ground with less effort. Based on the actual pile-driving implementation, around 30 percent to 50 percent of the piling resistance is caused by the interlock of the sheet pile. Therefore, the features of the present invention can reduce and overcome the weaknesses of the existing sheet piles. Further, the interlock (1) of present invention is adaptable to any shapes and configurations of sheet piles.

In the present invention, the stem (6) extends away from the engaging section (4) and connects to a web of the sheet pile. The angle of inclination between the stem (6) and the engaging section (4) of the interlock (1) of the present invention is greater than the prior art and existing sheet pile due to the curved surface of the engaging section (4). The angle of inclination between the stem (6) and the engaging section (4) of the interlock (1) is adjusted in accordance to the configuration of the engaging section (4) to ensure the overall rigidity and stability of the sheet pile. The adjustment of the angle of inclination between the stem (6) and the engaging section (4) is required since the vertical piling process will damage the sheet pile if the stem (6) of the interlock (1) which is connected to the web of the sheet pile is unable to support the vertical loads and to resist lateral pressure of the piling operation.

According to the preferred embodiment of the present invention, the first advantage of the interlock (1) is the higher rotational degree of the sheet pile when the interlock (1) is interlockably engaged with a corresponding interlock (G) of another sheet pile. Preferably, the interlock (1) of present invention can support up to 15 rotational degrees comparing with the prior art interlock that can only support up to 10 rotational degrees as shown in Fig. 2. When the rotational degree is higher, the space of adjustment of the interlock (1) will become greater. For the prior art interlock that could only support up to 10 rotational degrees, when a further adjustment of the sheet pile is required, the movement of the interlock may be restricted or the interlock may deform under the continuous piling stress and lateral pressure.

According to the present invention, the second advantage of the interlock (1) is the greater dimension of adjustment of the sheet pile when the interlock (1) is interlockably engaged with the corresponding interlock (G) of another sheet pile. When the interlock (1) is configured to have curved surface, the dimension of free play between the two interconnected interlock (1) is greater comparing with the prior art invention as shown in Fig. 3. Referring again to Fig. 3, by way of example but not limitation, the dimension of free play of present invention can increase from 2mm (distance a’ of prior art) to 5.6mm (distance a of present invention) vertically and from 3.7mm (distance b of prior art) to 4.2mm (distance b’ of prior art) horizontally. In percentage terms, the dimension of free play will increase by 280% vertically and by 13% horizontally in present invention comparing with prior art invention. When the space of adjustment of the interlock (1) increases, the contact friction within interlockably engaged interlocks will be reduced and it may avoid the condition of melting of the interlock (1).

In the present invention, the third advantage of the interlock (1) is the higher overall toughness of the sheet pile. Based on the practical usage, the higher rotational degree and the greater dimension of adjustment of the sheet pile can significantly level up the overall toughness of the interlock (1). The feature of higher toughness allows the sheet pile to absorb higher piling stress as generated during the pile-driving operation and to maintain the stability of the sheet pile element. Further, a stable sheet pile element can reduce the heat as generated during the pile-driving operation.

It will be appreciated that another advantage of the curved surface of the engaging section (4) of interlock (1) of present invention is the sheet pile is reusable after the construction work has been completed. This can reduce the cost of construction and also save the material used for the following construction projects. In contrast, if the interlock accidentally melts due to higher temperature generated by frictional action within interlockably engaged interlocks, the piling process will become more difficult and in the worst scenario, the piling process will also damage the sheet pile since the two sheet piles have been jammed as a connected element. The ability to install the sheet piles into a ground and the ability to remove the sheet piles from the ground will also be affected.

The foregoing description is considered as illustration of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.