Showing papers on "Caisson published in 1989"

Floating/tensioned production system with caisson

Abstract: A floating/tensioned production system for use in deepwater drilling and production operations generally combining a relatively small tension leg platform with a semisubmersible platform. The semisubmersible platform is provided with a working deck supported above the water surface so that an air gap exists between the working deck and the water surface. The tension leg platform provides a heave-restrained production deck for near-surface wellhead equipment. The production deck is supported above the drill site but beneath the water surface by buoyancy members and held in place by one or more tethers. Most other drilling and production equipment is located on the semisubmersible working deck. A caisson, surrounding the production deck, is used to provide a substantially dry working area. In one embodiment, the caisson is retractably attached to the production deck. In an alternative embodiment, the caisson is attached to the bottom of the working deck, extending downwardly to sealingly engage with the production deck.

Well head conductor and/or caisson support system

Abstract: What is provided is a system for supporting well production conductor and/or caisson which is extending above the water the line in an offshore setting, the system which includes a plurality of support clamps having a center located clamp portion for clamping around the exterior of the conductor and/or caisson, and four arm members radiating outwardly therefrom. Each of the arm members would support a piling clamp, each clamp having an opening therethrough for positioning on the sea bed; a second clamp is positioned around the conductor and/or caisson, at the level of the water, the configuration likewise having a plurality of arm members supporting a piling clamp on each end therefrom, the clamp members are aligned at the water level with the clamp members on the floor of the sea bed; introducing a piling through each of the piling clamps at the water level, and driving the piling through to each of the clamps on the floor of the sea bed to a depth so that the plurality of pilings, spaced apart and supported by the clamps support the conductor and/or caisson in the upright position against the lateral forces of the sea.

Cable-stayed bridge and construction process

Abstract: A cable-stayed bridge including at least one concrete platform consisting of an assembly of caisson elements, at least partly prefabricated, extending transversely to the bridge. Each element is composed of an upper table and a lower table separated by spaces which extend transversely to the platform, and are connected by walls at the side and the end, and with longitudinal intermediate partitions and transverse partitions. The piers of the bridge extend preferably upwards to the platform and carry both a part of the platform and the pylon.

Method of erecting offshore platforms

Abstract: Method of erecting a minimal structure offshore platform around an existing caisson or drive pipe without any bolted, grouted, or underwater welded connections. This method involves the welding of a stop ring onto the caisson at a point just above the water line. A template having two sleeves for receiving piles and a sleeve for receiving a caisson is lowered over the caisson until the template rests on the stop ring. The template is concentrically aligned by a shim mounted to the top of the caisson sleeve. The caisson sleeve is centered around the caisson by inserting shims between the caisson and the caisson sleeve, and then the caisson sleeve is welded to the caisson and the stop ring. Piles are driven through the pile sleeves to grade using shims on the high point of the pile sleeve to align the pile with the axis of the sleeve as the pile sections are welded together. Once the piles are driven, the pile sleeves are centered around the piles by inserting shims between the piles and the piles sleeves. The pile sleeves are then welded to the piles. The deck of the structure is then installed using the template as the support.

Joint material for caisson

Abstract: PROBLEM TO BE SOLVED: To prevent generation of gap at the time of relative displacement between upper and lower positions of caisson by arranging a hollow main body made of elastic material having an opening, fitting an inner bag in the hollow part for integral connection, and allowing the inner bag to swell by a cut part at a lower end. SOLUTION: A joint member 10 for a caisson is fixed to a caisson end face by means of a flange 12 and a filler of rough sand, etc., is filled into a hollow part of a main body 11 from an opening, then the main body 11 swells out in the circular direction due to the filling pressure. Thereby a front face is brought into pressure contact with an adjacent caisson end face and an inner bag 13 is pressure inversed by the filler and pushed out form a lower end of the main body 11. The inner bag 13 is swelled out ahead from a cut part 14 and is brought into close contact with cobble stone and adiacent caisson. When a relative replacement generates between the caisson fitted with the joint member 10 and adjacent caisson due to shrinkage or sink of the ground after the execution, the main part 11 swells to prevent generation of gap. Accordingly, the close contactconditions are maintained corresponding to the step difference in the foundation, and flow-out or water immersion from the gap is thus prevented.

Sinking method for open caisson and device thereof

Abstract: PURPOSE: To prevent over-sinking and economically sink a caisson body by pressing the lower face of a reaction plate to the ground to obtain the reaction force from the ground, sinking the caisson body, then introducing pre-stress via lowering steel wires. CONSTITUTION: Center haul jacks 33 are operated, and a reaction plate 2 in a caisson body 1 is located on the soft ground 6 via hoisting PC steel wires 3. Center haul jacks 45 are operated, the upper sections of lowering PC steel wires 4 are pulled downward, the lower face of the reaction plate 2 is pressed to the surface of the soft ground 6 to obtain the reaction force, and the caisson body 1 is sunk to the preset depth. Lowering steel wires 4 are cut in the middle, and cut lower end sections are fixed to the caisson body 1 with a fixing agent. Upper sections of lowering steel wires 4 are pulled upward by center haul jacks 45 to introduce the required pre-stress to the caisson body 1. COPYRIGHT: (C)1991,JPO&Japio

A Lateral Load Test on Seven Foot Diameter Caissons

Abstract: Seven foot (2.1 m) diameter caissons (drilled shafts) were designed to support a mainline eastbound bridge and an off-ramp of Interstate Highway 70 in Glenwood Canyon, Colorado. A lateral load test was proposed and completed during the construction phase of the project to evaluate the caisson construction method and the response of the caissons to the large lateral design loads. Soil parameters were back-calculated from load-deflection and inclinometer data using a p-y analysis. Based on the lateral load test results, the adjusted soil parameters permitted shortening of the caissons and an improved construction schedule.

Settling control system for pneumatic caisson

Abstract: PURPOSE:To contrive unmanned operations with high efficiency at construction site by providing monitors connected to television camera attached to an excavating mechanism and a pneumatic operation room, a computer, and an excavation operating board for the centralized control room of the ground's surface CONSTITUTION:An excavator mechanism 11 movable along rails 10 is set on the downside of the bottom board 1a of a caisson 1, and an excavator camera 12 and a caisson camera 13 are attached to the downside of the bottom 1a and the mechanism 11 In the centralized control room 26 of the ground's surface, a personal computer 27, a printer 28, an excavation operating board 33, and CRT excavation monitor 30 connected with the cameras 12 and 13 and an operating room monitor 31 are set The settling and excavating conditions of caisson and the condition of surrounding ground are grasped through various sensors, and data are quickly processed A series of control and operation can thus be performed only the the centralized control room 26 while watching the screen 30 and 31

Operation controller for excavator in pneumatic caisson work

Abstract: PURPOSE:To permit unmanned excavation work to be performed by a method in which various sensors are attached to a caisson body and an excavator, and information from the sensors is displayed on a monitor for remote control of the excavator. CONSTITUTION:A supersonic waves probe 21 to measure the depth of excavation in the bottom of operation room is set in a matrix form on the ceiling of the operation room of caisson body 1. Sensors 27, 28, and 29 to detect the traveling position, slewing angle, and tilting angle of an excavator 6 are provided for the excavator 6. The detected signals from the probe 21 and the sensors 27, 28, and 29 are analyzed by a computer set outside of the operation room and displayed on a displayer for monitoring, thereby operating the excavator 6.

Bottom-spreaded open caisson foundation

Abstract: PURPOSE: To enlarge supporting area for a vertical load by drilling the lower end part of an annular groove with a bottom spreading drilling machine and constructing an open caisson foundation made of cast-in-place concrete provided with projecting parts on both sides, inner and outer, of the lower end of a cylindrical wall body. CONSTITUTION: A circular guide wall is previously constructed on the surface of the earth, and an annular groove is drilled. Nextly, the lower parts of chain cutters 9 on both sides are gradually expanded sidewards through expanding ring arms 11, by actuating the spreading hydraulic jack 10 of a bottom spreading drilling machine. Sequentially, an enclosed type electric motor 5 is driven, the chain cutters 9 are rotated in the arrow mark direction through a rack 7 and pinions 8, and projecting parts 2, 2' are drilled. After completion of the drilling work, suitable arrangement of reinforcement and concrete placing in the drilled groove is performed. Hereby, supporting area of vertical area is enlarged, and a large vertical load can be supported with a little material. COPYRIGHT: (C)1990,JPO&Japio

Detection and correction of inclination of caisson

Abstract: PURPOSE:To simply and quickly correct the inclination of caisson by a method in which the inclination of caisson is automatically detected by an inclination sensor and a liquid-pressure jack facing the outside of caisson on the settling side is worked toward the pressing direction by the detected signal of the inclination sensor. CONSTITUTION:In settling a caisson 1 down, when the caisson 1 begins to incline, the inclination is detected by an inclinometer affixed on the outside of the caisson 1 and also by an inclinometer 11 set on the downside of the ceiling slab 10 of the caisson operating chamber. The detected signal is sent to a computer 12 and a control signal from the computer 12 is sent to a control board 13. The control signal is sent from the board 13 to an operating board 17 on the settling side of the caisson and the high-pressure pump of a pump device is operated by signals from the board 17. A solenoid valve 14 for operating jack is switched. Pressure liquid is further sent to the basal end side of the cylinder 6 of a liquid-pressure jack on the settling side and the settling side of the caisson 1 is pressed by the jack 2 to correct the inclination of the caisson 1.

Connected wave-resistant work for seaside levee

Abstract: PURPOSE:To raise the resistance to waves of a levee by a method in which levees formed by placing concrete to the top portion of a caisson erected on rubble mound are closely connected with each other to form an integrated levee body. CONSTITUTION:A seaside levee made of caisson 3, blocks, cellular blocks, underwater concrete, etc., is constructed on the seabed or rubble mound 4 formed on the seabed. Concrete 1 is placed on the caisson, etc., to construct the upright dike or mixed dike of the seaside levee. The in-situ top concretes of the caisson are mutually connected by a connector 2 in the longitudinal direction of the levee so constructed, thereby integrating the levee and strengthening the resistance to waves.

System for collecting and handling refuse

Abstract: The invention relates to a system for collecting and handling refuse and other waste, of the type including an openable container equipped with orifices for the introduction of the waste, as well as means making it possible to raise and/or move it. This system is characterised in that it comprises a caisson 1 of general parallelepipedal form, with an open base, equipped with two jaws 6 which are articulated on the lateral faces of the caisson 1 in order to be capable of pivoting between a position in which they conceal the base of the latter and a position in which they reveal it, as well as a tie rod 10 capable of sliding vertically on each lateral face of the said caisson 1 between a low position in which it locks the jaws 6 of the caisson 1 in their closed position and a high position in which it acts, via a cam surface 16, in order to separate them from each other. Application to the collection of domestic refuse.

Hydrophilic type wave absorbing structure

Abstract: PURPOSE:To provide a hydrophilic type wave absorbing structure without damaging properties of buried bank or breakwater by providing a plurality of steps sequentially, constructing a multistage open ditch at the cross section, a plurality of weirs in the direction of the longitudinal section of the open ditch so as to provide a passage for seawater. CONSTITUTION:On upper part of a caisson 20 on a side buried, there is provided with steps such as a place 7 for rest with stairs and a parapet 8, wherein the caisson 20 is provided with an open ditch composed of water passage 3 in the form of multistep in cross section for water playing. The water passage 3 is in the form of stairs with steps in the direction of the longitudinal section of the caisson 20, and each steps has a weir at its end to communicate with an access 11 to seawater. It is thus possible for dabblers to be acquainted with the sea and to ensure safety with the breakwater for dissipating waves.

Structure of embankment

Abstract: PURPOSE:To reduce water pressure applied to the wall of embankment and make the wall in small thickness by placing caissons each having a plurality of chambers ring-shapedly at the sea ground, and introducing sea water so that the water level sinks gradually from the chamber nearer outside the embankment toward the one inside it. CONSTITUTION:Each caisson 1 is formed so that the top plate 3 lowers gradually from outside the embankment toward inside it, and such caissons 1 are put parallelly on sea ground so as to form a ring-shaped embankment. Sea water is introduced into chambers 7a-d in the caisson 1 so that the water level lowers from the chamber 7a at the outside of embankment toward the chamber 7d inside it. This lessens the water pressure applied to the walls of the caissons and bulkheads 6a, 6b, 6c inside it, which enables decreasing the wall thickness.

Displayer for attitude of excavation shovel for pneumatic caisson

Abstract: PURPOSE:To permit unmanned operations in a pneumatic caisson by a method in which sensors are attached to each moving part of an excavating shovel, and on the basis of output signals of the sensors, the moving amounts of each moving part are calculated and displayed in image form. CONSTITUTION:Sensors 12, 13, 15, 16, and 17 are attached to the frame 3, rotary frame 5, first boom 7, second boom 9, and bucket 10 of an excavating shovel 1 for pneumatic caisson, by which the moving amounts of them are detected. On the basis of output signals S1-S5 of the sensors 12, 13, 15, 16, and 17, the attitude of each moving part is calculated in an attitude arithmetic unit 20, converted into image signals in a display arithmetic unit 21, and displayed on a displayer 22.

Method for forming openings in structures of the water tower type

Abstract: The method for forming openings in structures of the water tower type uses a formwork consisting of external panels 5 and internal panels 2 held by struts 3. These panels 2, 5 and struts 3 are arranged in the form of superimposed rings, and the structure progresses by taking the lower ring and bringing it continually to the top. The method according to the invention consists in inserting, between the external panels 5 and internal panels 2 of the formwork, a caisson 6 preferably having a prismatic shape, which caisson comprises, in its lower part and in its upper part, means cooperating with the adjacent lower or upper caisson. The caissons 6 can be reused as the formwork progresses.

Timbering work and overflow preventing wall in superstructure construction of caisson and the like

Abstract: PURPOSE:To permit dry-construction work as well as secure operating space by a method in which the first and second cut-off walls of a given structure are attached in combination according to the shape of the upper edge of caisson, etc, to form the timbering work for the superstructure by using the over-hanging parts of the walls CONSTITUTION:A timbering work and overflow preventing wall 10 is made up of the first cut-off structures J, L, N, O, Q, R, and T which are divided into blocks according to the shape of the upper edge of caisson 1 and the second cut-off structures K, M, P, and S The first cut-off structures have frames detachably attached by extending outwards to the upper edge of the caisson 1, having a height enough to prevent overflowing of waves The second structures cover detachably the apertures of the first cut-off structures

Inter-caisson water stopping method

Abstract: PURPOSE:To stop water certainly and reduce the cost by interposing water- absorbing expansive rubber between caissons constituting an embankment. CONSTITUTION:Caissons 3 each in the form of a hollow box constituting an embankment 2 are placed on the water bottom 1 with a gap S reserved between each pair of adjoining ones. A plate-shaped water-absorbing expansive rubber 5 having the same area as the sectional area of caisson 3 is inserted in the middle of this gap S. Absorbing the water, this rubber 5 expands and chokes the gap S completely to come in close contact with the wall surfaces 4 of the two caissons 3.

Controller for sinking caisson

Abstract: PURPOSE:To reduce the number of operators as well as to make overall operations performable safely and speedily by installing an electronic controller, and making it control these operations for position judgement, alignment, attitude holding, lowering or the like collectively and automatically. CONSTITUTION:A caisson 20 is hung down from pontoons 21, 21 on the water via wires W-1, W-1, while steering wires W2-1-W2-4 are arranged from the four corners and pulled toward sinkers 23, 23 on the seabed. Next, any positional slippage of the caisson 20 is judged by a position judging means 3, and according to this judgement, a winch 2 is operated by an alignment means and thus the position is corrected. Then, another winch 1 is operated by an equivalent weight lowering means 5, lowering the caisson 20 as far as the specified value, and then this operation is repeated by a repeating means 7. Furthermore, during this while, an attitude of the caisson 20 is justly held by an attitude holding means 6. Then, these serial operations are collectively and automatically controlled by an electronic controller 25 installed on the pontoon 21.

Construction of cut-off wall of caisson and its reuse

Abstract: PURPOSE:To make reconstruction of cut-off wall of caisson easier by a method in which many ring-shaped cut-off walls are orderly constructed on the top of a caisson being set, piers are constructed in the caisson, and the cut-off walls are orderly laminated through water-stop packing on the top of the other caisson. CONSTITUTION:Concrete is placed to from a caisson 2, during which period the caisson 2 is settled down to a given depth. Many ring-shaped cut-off walls 1 are formed on the top of the caisson 2 by placing concrete. After a pier 10 is constructed in a dry state inside the walls 1, and the walls 1 are then orderly removed from above by cutting off the sheet of water-stop material 8 and again laminated through a ring-formed rubber gasket for stopping water on the top of the other caisson to reconstruct the cut-off walls 1. The removing operation of the walls 1 can thus be safely and easily made and the reconstruction of the cut-off walls can also be simplified.

Method and device for installing caisson

Abstract: PURPOSE:To make installation accurate by a method wherein water is injected into two base ships connected by a beam at an interval, two wire ropes are fixed to a caisson, the base ships are floated, the caisson is moved to an erection location and water is injected and the caisson is installed. CONSTITUTION:Frames 4 for supporting a beam are disposed in upright onto workboats 1a, 1b respectively, and the beam 6 made of steel is installed through ball joint mechanisms 5, thus constituting one catamaran type workboat. Base ships 1 are shifted to both sides of a caisson 2 temporarily positioned under a water surface, water is injected by a pump 3 and the base ships 1 are sunk, and ropes 7 are engaged with hangers 10 on the top face of the caisson 2. Water is drained by pumps 3 and the base ships 1 are floated, and the base ships are moved up to the erection location 13 of the caisson. Water is injected into the base ships 1 and the base ships are sunk, the bottom of the caisson is grounded, and the ropes 7 are removed and the base ships 1 are detached and shifted. Accordingly, the caisson can be installed accurately in shallow water.

Continuous placement of concrete underwater

Abstract: PURPOSE:To simplify the operations as well as to save power by a method in which a flexible hose for placing concrete is raised as the placing operation of underwater concrete advances CONSTITUTION:A crane 1 is set on a caisson 11 settled on the seabed at deep water depth, and a winding drum 5 to wind up or down a flexible hose 3 for placing concrete is set on a base 2 hung down from the winding wire 4 of the crane 1 The hose 3 is lowered to a placing position and underwater concrete is placed The hose 3 is then raised and while moving the placing position upwards underwater concrete is continuously placed Underwater concrete can thus be placed without discontinuation of the operations and with high efficiency

Great depth pneumatic caisson and its load work involved with the efficiency of respiratory protection

Abstract: Pneumatic caisson work in Japan has been in operation since 1924. Afterward, this technique of compressed air work has been utilized in the constructions like as foundation works, the basements, and shafts of the bottom tunnel or shields for subway and so forth. While, it means for people to be exposed to hyperbaric environment that they use compressed air work, this technique has risks to be suffered from not only decompression sickness (DCS) but toxicity of poisonous gas or oxygen deficiency. However, this technique is necessary for urban civil engineering and recent compressed air works over than 1.0 kg/cm2 has been increased in 1.5 times more than in 1970's and the higher compressed air work more than 4.0 kg/cm2 will be actually planned in near future. So unmanned caisson work is considered as a better technique for such high pressure work, even though people must enter into hyperbaric working fields for maintenance or repair of unmanned operated machinery and materials. This research is to establish the safety work under hyperbaric environment within 7 kg/cm2. It is necessary for us to establish the system not only to keep safety but to maintain working efficiency. According to obtain the purpose, the effect of respiratory protection has been investigated and work load under hyperbaric caisson work has also been studied.

Double-cylinder type wave control structure

Abstract: PURPOSE: To obtain a high wave-breaking effect by juxtaposing a large number of double-cylinder type caissons in such a way that the abutment plane walls thereof are abutted to each other, so that a large resistance can be given to waves for dispersing energy. CONSTITUTION: On the bottom plate 1 of reinforced concrete, an outside cylinder 2 is erected, and on the outer lower parts thereof, abutment plane walls 3, 3 are oppositely provided. In the inside of the outer cylinder 2, an inner cylinder 6 is erected so as to form a ring-shaped free water part 8 between both cylinders 2 and 6. And, in the upper part of the outer cylinder 2 on one side between the abutment plane walls 3, 3, a large number of water-passing holes 4 are provided; while in the upper part on the other side, a large number of water-permeating holes 5 are provided for constituting a double-cylinder type caisson A. Then, a large number of caissons A are juxtaposed in such a way that the abutment plane walls 3, 3 are abutted to each other. While waves pass through the caisson A, a large resistance is give to the waves through the passage, diversion, confluence, mixture, and permeation of water, and most of energy is dispersed. COPYRIGHT: (C)1991,JPO&Japio

Aseismic reinforcing construction for structure

Abstract: PURPOSE:To facilitate execution of works and enhance the water exhausting characteristic by holding the top of a bored pile in a caisson mound, absorbing excessive gap water pressure from a hole in the liquefied layer position, and exhausting water from a hole in the mound position. CONSTITUTION:Below a caisson 1, a bored pile 4 provided with a number of small holes 5 for water communication is placed in such a way that at least the bored part is located in a liquefied layer 6 below a mound 7. As long as the bored part of the pile 4 lies within the liquefied layer 6 and the mound 7, the top of the pile 4 may be positioned at any level in the mound 7. Placing of the pile 4 is conducted by the use of a casing pipe.

Geophysical and Nuclear Methods for Non-Destructive Evaluation of Caissons

Abstract: Non-destructive testing techniques were used to confirm the concrete integrity on the caisson foundations for the 45-story Ohio Corporate Headquarters building in Cleveland, Ohio. The caissons are believed to be the deepest on the North American Continent, extending as much as 250 ft [76m] below ground surface and constructed entirely under water by tremie and pumped concrete techniques. The integrity testing program, including required calibration, is described and the results presented and discussed. Problems encountered during construction that were detected with the integrity testing program are also discussed.

Construction of closed wall foundation in the sakitama bridge

Abstract: P 15 foundation in the Sakitama Bridge for a loop road around Tokyo, consists of a highway foundation and twin local road foundation. The Closed Wall Foundation by means of diaphragm wall was adopted for the highway foundation because it was provided between the caisson foundation of local road previously constructed. This method, the construction of closed wall foundation, enable to construct deep foundation safely without disturbing the surrounding soils, but it has less applications. Therefore, for further effective application, the design and construction method have been investigated during this work. This report is described about the result of design, construction and investigation for this work.

Method of constructing shore protection structure

Abstract: PURPOSE: To enable simple execution of a work at a low cost by a method wherein a structure is sunk in water in a manner that a pile head protruded from a sea bottom is inserted in the joining hole of a concrerte structure, and underwater concrete is placed in the joining hole and a gap between piles to secure a caisson. CONSTITUTION: After a pile 1 is driven in a seat bottom, the pile is cut at a given height so that a pile head part 1a is protruded from the sea bottom. After a caisson, being a concrete structure, having a floating chamber 4 and a joining hole 5 formed in a bottom plate 6 is manufactured, the caission is floated in water and tagged to a place, where the pile 1 is driven, by means of a boat 3. Through regulation of injection of water in the floating chamber 4, the caission is sunk, and the pile head part 1a is inserted in the joining hole 5. Further, underwater concrete 9 is placed in a gap between the pile 1 and the joining hole 5 to secure the caisson. COPYRIGHT: (C)1991,JPO&Japio