This invention relates to a cut and cover method of constructing grade separation structures. The methods include partially burying precast substructure elements with associated trench boxes under live traffic. Once the precast substructure elements are buried the substructure is completed and the bridge span is installed. Other methods include installing precast superstructure elements with form-work system and forming a bridge substructure and excavating underneath the superstructure once the substructure is formed.

A suction anchor and method of installing the suction anchor. The suction anchor including a suction chamber bounded by: a circumferential outer wall; an upper wall; and an internal housing wall. The internal housing defining a passage for receiving wellhead components that may be secured to the suction anchor. The suction chamber has a minor upper portion and a major lower portion. The minor upper portion having internal reinforcing members extending along the inside of the upper wall from the outer walls to the internal housing. The major portion is adapted to be embedded in a seabed and the minor portion is adapted to project from the seabed when the anchor is installed. The reinforcing members serve to reinforce the upper wall of the chamber against collapse and to rigidly support the internal housing to resist forces arising from bending moments applied to wellhead components received and secured therein.

The invention relates to a seabed foundation (1) for an offshore facility, comprising a primary pressure chamber (7) connected to a primary pump (8) and one or more secondary pressure chambers (9) connected to one or more secondary pumps (10). According to an embodiment of the invention, said primary pump is a suction pump and said secondary pump is a pressure pump. The invention further relates to a method (12) of installing said foundation on the seabed (19), which comprises the steps of activating (14) said primary pump to create negative pressure in the primary pressure chamber (7), so that the foundation sinks into the seabed, and activating (15) said one or more secondary pumps (10) to create positive pressures in the secondary pressure chambers (9), so as to control the alignment of the foundation with respect to a substantially horizontal axis (16) during the sinking into the seabed.

The invention relates to a seabed foundation (1) for an offshore facility, comprising a primary pressure chamber (7) connected to a primary pump (8) and one or more secondary pressure chambers (9) connected to one or more secondary pumps (10). According to an embodiment of the invention, said primary pump is a suction pump and said secondary pump is a pressure pump. The invention further relates to a method (12) of installing said foundation on the seabed (19), which comprises the steps of activating (14) said primary pump to create negative pressure in the primary pressure chamber (7), so that the foundation sinks into the seabed, and activating (15) said one or more secondary pumps (10) to create positive pressures in the secondary pressure chambers (9), so as to control the alignment of the foundation with respect to a substantially horizontal axis (16) during the sinking into the seabed.

A suction anchor and method of installing the suction anchor. The suction anchor including a suction chamber bounded by: a circumferential outer wall; an upper wall; and an internal housing wall. The internal housing defining a passage for receiving wellhead components that may be secured to the suction anchor. The suction chamber has a minor upper portion and a major lower portion. The minor upper portion having internal reinforcing members extending along the inside of the upper wall from the outer walls to the internal housing. The major portion is adapted to be embedded in a seabed and the minor portion is adapted to project from the seabed when the anchor is installed. The reinforcing members serve to reinforce the upper wall of the chamber against collapse and to rigidly support the internal housing to resist forces arising from bending moments applied to wellhead components received and secured therein.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.

According to an embodiment, a first concrete block is installed in a state in which a tubular waterproof membrane and a guide pipe are temporarily coupled to the first concrete block, then a second concrete block is installed, and subsequently concrete is poured into the tubular waterproof membrane and the guide pole is removed to form a concrete column, thereby allowing the concrete column to be connected to a body of the first concrete block by means of a column rebar assembly, such that the lower end of the concrete column is formed very firmly to thus greatly improve the stiffness of the entire concrete block structure. In addition, since the concrete column is formed by means of the concrete poured into the tubular waterproofing membrane, the concrete column can be formed in the same way as that in the land environment.

According to an embodiment, a first concrete block is installed in a state in which a tubular waterproof membrane and a guide pipe are temporarily coupled to the first concrete block, then a second concrete block is installed, and subsequently concrete is poured into the tubular waterproof membrane and the guide pole is removed to form a concrete column, thereby allowing the concrete column to be connected to a body of the first concrete block by means of a column rebar assembly, such that the lower end of the concrete column is formed very firmly to thus greatly improve the stiffness of the entire concrete block structure. In addition, since the concrete column is formed by means of the concrete poured into the tubular waterproofing membrane, the concrete column can be formed in the same way as that in the land environment.

Extensible shells and related methods for constructing a support pier are disclosed. An extensible shell can define an interior for holding granular construction material and define a first opening at a first end for receiving the granular construction material into the interior and a second opening at a second end. The extensible shell can be flexible such that the shell expands when granular construction material is compacted in the interior of the shell. A method may include positioning the extensible shell in the ground and filling at least a portion of the interior of the shell with the granular construction material. The granular construction material may be compacted in the interior of the extensible shell to form a support pier.