SU1411367A1 - Offshore stationary platform - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to hydraulic engineering. The purpose of the invention is to reduce metal consumption when installing the platform on weak soils. The offshore platform includes deck 1, support structure 2, piles 4 rigidly connected to the support structure. When installing the platform on weak soils, the rigidity of the pile bush in the zone of weak soil 3 is increased by installing elastic elements 6 at different angles relative to the longitudinal axis of each pile. The elastic elements 6 are connected by the upper ends with the base of the supporting structure, and the lower ends are connected with their own ones in the contact zone of weak and supporting soils. The lower ends of the piles are fixed with the help of nozzles and fixed by means of the stops 9. The supporting structure is installed on weak soil with nozzles with elastic elements fixed on its base and the pile is driven through rails and nozzles. The stops fixed on the piles rest against the nozzles and sink together with elastic elements into the weak ground to a predetermined depth. 2 Il. € (L

Description

MCh1IK1HG 11RU

with

ABOUT)

The invention relates to the construction and can be used in the construction of offshore platforms intended for the exploration and exploitation of oil and gas fields and established on weak soils in the waters of the freezing seas.

The purpose of the invention is to reduce metal consumption when installing the platform on weak soils.

FIG. 1 depicts a marine stationary platform installed on weak soils; in fig. 2 is a section A-A in FIG. one.

The offshore stationary platform contains deck 1, support structure 2 installed on weak soil 3, piles 4 embedded in dense soil 5 and rigidly connected to support structure 2. In the zone of weak soil 3, elastic elements 6 are installed, which are connected to the base with their upper end 7 supporting structure 1, 2, and the lower end - with nozzles 8 | on the pile x 4, fixed by iynopoB 9 in the contact zone of weak 3 and dense 5 soils. The angle of inclination of the elastic elements to the longitudinal axis of each pile is determined by the calculation in the design and lies in the interval from ot arctg to

j arctg2.a, i / h.

The platform works as follows.

I The support structure 2 takes the load from deck 1 with the equipment placed on it, its own weight and from the horizontal pressure of the ice. As a result, the momentum M acts on the 1st shaft, the transverse force IQ and the longitudinal force N. As a result of the installation of elastic elements, the rigidity of a part of the pile bush located in the | weak ground increases, which leads to a decrease in the displacements of the base structure moments in the most loaded pile x.

The installation of elastic elements that work on stretching at different angles to the longitudinal axis of the piles allows the loading of a large bending moment M of the pile Less loaded by the longitudinal force N, and

design the structure so that the stresses in all the piles are close in magnitude, i.e.

 Wi

Mi

b. b ..,. - + m

0

5 0 5

0

five

0

five

where А „is the pile section area;

Wfl- moment of resistance of the pile.

As a result, it is possible to reduce the cross sections of the piles, or to reduce the total number of piles, which is more economically feasible.

The platform is set as follows.

The support structure with nozzles 8 fixed to its base with elastic elements 6 is installed on weak soil and piles 4 are driven through guides and nozzles. The stops fixed on the piles rest against the nozzles and immerse them, together with elastic elements, in a weak ground to a predetermined depth. After driving the pile onto the supporting structure, install the deck with the equipment.

The advantages of the proposed construction of a fixed offshore platform on weak soils are that, with the same material capacity, the bearing capacity of piles can be significantly increased, or with the same carrying capacity, metal intensity of piles can be reduced by reducing cross sections or reducing their number.

Claims (1)

Invention Formula The offshore stationary platform includes a deck, a support structure and piles, buried in dense soil, rigidly connected to the support structure, meaning that, in order to reduce metal consumption when installing the platform on weak soils, the support structure is equipped with flexible elements placed in the zone of weak soil and fixed upper ends to the base of the support structure, and the lower ends to the ground in the contact zone of weak and dense soils by means of nozzles mounted on the ground and fixed on using stops. Fi & .2