RU2370594C1 - Pile support of marine hydrotechnical structure - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: pile support of marine hydrotechnical structure, rod structure (1) of which consists of tubular elements and comprises angular and intermediate support stands (2), inside of which the main piles (2) are installed, being joined to appropriate support stands (2) by cement mortar (4), differing by the fact that rod structure (1) is additionally equipped with telescopic piles (5), external cylinder (6) of each telescopic pile (5) is rigidly connected to rod structure (1), internal cylinder (7) by open end interacts with soil, and closed end of internal cylinder (7) and its side surface are rigidly connected to internal surface of external cylinder (6) with the help of cement mortar (4).

EFFECT: improved bearing capacity, reduced labour intensity and cost of marine operations in production of pile works in process of structure fastening to sea bottom.

4 cl, 7 dwg

Description

The invention relates to marine hydraulic structures with pile supports, mainly to the construction of offshore technological platforms for mining.

A self-aligning platform is known, characterized by the presence of ballast tanks, which are used when transporting the platform, to maintain a given buoyancy when the base is submerged on the sea bottom, to stabilize and maintain the vertical position of the base when installed on the ground, then crush hollow cylindrical piles into the ground under the platform’s own weight, soil absorption into hollow cylindrical piles, and the subsequent removal of ballast tanks [1].

The disadvantage of this technical solution is that it does not provide the necessary deepening of piles due to the suction effect to achieve the necessary load-bearing capacity of piles at shallow depths (less than 30-50 m). Achieving the necessary bearing capacity by increasing the depth of immersion of the pile into the ground is complicated for platforms with significant loads from the effects of waves, ice and seismic.

A technical solution is known, which is characterized in that the pile support of a marine hydraulic structure, the core structure of the pipe elements of which contains angular and intermediate support posts, inside of which are located the main piles associated with the respective support posts by cement mortar [2 - prototype].

The use of such a technical solution as a support for hydraulic structures has a low bearing capacity on soft soils.

The present invention is aimed at increasing the bearing capacity of the structure, as well as reducing the complexity and cost of offshore operations in the manufacture of pile work while securing the structure to the seabed.

This goal is achieved by the fact that at the base of the offshore hydraulic structure the rod structure of the support consists of pipe elements and contains angular and intermediate support posts, inside of which there are piles connected to the respective support posts by cement mortar, while some of the piles are equipped with additional telescopic structures in such a way that the outer cylinder of each telescopic pile is rigidly connected with the rod structure of the support, the inner cylinder interacts with the open end ground, and the closed end of the inner cylinder and its side surface is rigidly connected to the inner surface of the outer cylinder via cement slurry.

In addition, in one embodiment, the piles in the racks are made in the form of driven piles and / or in the form of crushed piles and are located in the central part of the rod structure of the support, while telescopic piles are located on the outer perimeter of the rod structure of the base.

In one preferred embodiment, telescopic piles are located in the central part of the rod structure of the support, and driven piles and / or crushed piles are located on the outer perimeter of the rod structure.

The invention is illustrated by drawings.

Figure 1 shows the pile foundation in the composition of the offshore oil and gas field stationary platform with a spatial rod structure of the bearing support.

Figure 2 is a top view along aa in figure 1.

Figure 3 shows a schematic diagram of a pile foundation of a rod supporting structure with a central point bearing support.

Figure 4 is a top view of figure 3.

Figure 5 is a diagram of the installation of a telescopic pile, 5a is the initial position, 5b is the deepening of the inner cylinder of the telescopic pile into the soil, 5c is a rigid connection of the outer and inner cylinders of the telescopic pile by injection of cement mortar.

Pile support of an offshore hydraulic structure includes a rod structure 1 of pipe elements. The rod structure 1 contains angular and intermediate support posts 2, inside of which the main piles 3 are located. The main piles 3, driven or crushed, are connected with the corresponding support posts 2 by cement mortar 4.

The rod structure 1 is equipped with additional telescopic piles 5. The outer cylinder 6 of each telescopic pile 5 is rigidly connected to the rod structure 1, the inner cylinder 7 with an open end interacts with the ground, and the closed end of the inner cylinder 7 and its side surface are rigidly connected with the inner surface of the outer cylinder 6 using cement mortar 4.

The main piles 3 can be made of two types - driven or crushed, which are installed in the ground using the appropriate type of equipment.

In one embodiment of the pile support of a hydraulic structure (FIGS. 1, 2), the main piles 3 are located in the central part of the core structure 1, with additional telescopic piles 5 located along the outer perimeter of the core structure 1 of the base.

An embodiment of a pile support of a hydraulic structure is also possible (Figs. 3, 4), in which additional telescopic piles 5 are located in the central part of the base core structure 1, and the main piles 3 are located on the outer perimeter of the core structure 1.

Installation of telescopic piles 5 is as follows. The immersion of the telescopic pile 5 in the ground is ensured by crushing it into the soil due to the vertical load from the weight of the structure (Fig. 5a) and immersion in the soil of the internal movable telescopic part of the cylindrical pile 7 due to the suction effect (Fig. 5b) created in the inner cavity of the stationary outer cylinder 6 and the upper part of the inner cylinder 7 (Fig.5b).

The suction effect is achieved due to the vacuum created by the pump when pumping air from the inner cylinder 7 of the cylindrical pile 5 and soil, and the hydrostatic pressure is achieved due to the pressure created by the pump when pumping water into the inner cavity of the stationary outer cylinder 6 and the upper part of the inner cylinder 7.

The pumping of water from the inner cylinder 7 and the injection of cement mortar 4 into the annular space with the formation of cement plugs is carried out using pumps located on the construction or on a floating vehicle designed to carry out these works (figv).

The sequence of installation and fastening of the pile support on the seabed as part of a stationary marine platform is as follows:

- installation on the seabed using transport barges using special devices for the cargo descent of the platform to the seabed (not shown);

- deepening into the soil of the pile foundation with telescopic piles due to its own weight (figa);

- penetration into the soil of the pile support due to the effect of absorption and hydrostatic pressure, taking into account the sequence of penetration of each pile (fig.5b).

- installation of driven and / or crushed piles with a tight connection with the rod support using cement mortar (pigv).

Thus, the proposed technical solution allows for a universal method of installing and securing a pile support on the seabed as part of a stationary offshore platform, taking into account increased reliability with different soil characteristics and sea depths.

Information sources

1. Project SPT Offsore - SIP 1 Feed Stady, October 2007.

2. RF patent 1102844, cl. E02B 17/00, 2004.

Claims (4)

1. Pile support of an offshore hydraulic structure, the rod structure of which consists of pipe elements and contains angular and intermediate support posts, inside of which are piles connected to the corresponding support columns with cement mortar, characterized in that some of the piles are equipped with additional telescopic structures so that the outer cylinder of each telescopic pile is rigidly connected to the rod structure of the support, the inner cylinder interacts with the ground with the open end, and the dug end face of the inner cylinder and its side surface are rigidly connected to the inner surface of the outer cylinder using cement mortar, while the pile is immersed in the ground by crushing the bottom of the cylindrical body into the ground due to the vertical load from the weight of the structure and by immersing the lower movable telescopic part of the cylindrical into the ground piles due to the absorption effect created in the inner cavity of the movable pile and soil, and due to the hydrostatic pressure created in the inside It cavity fixed, cylindrical body and upper movable part. 2. The pile support according to claim 1, characterized in that the main piles in the uprights of the support block are driven or crushed. 3. The pile support according to claim 1, characterized in that the crushed or driven piles are located in the central part of the core structure, while the telescopic piles are located on the outer perimeter of the core structure of the base. 4. The pile support according to claim 1, characterized in that the main piles are located on the outer perimeter of the core structure, and telescopic piles are located in the central part of the core structure of the base.

Images