JP5746126B2 - Quay crane - Google Patents

Description

  The present invention relates to a quay crane having a countermeasure against earthquakes applied to a crane or the like used for container handling at a port or an inland container terminal, and a control method thereof.

  Container terminals such as harbors and inland areas handle containers between ships and trailers by quay cranes, portal cranes, and container trailers. As an earthquake countermeasure in this container terminal, a crane having a seismic isolation structure in a quay crane has been proposed (see, for example, Patent Document 1). This seismic isolation structure prevents the crane from receiving seismic force by insulating the ground and the crane.

  On the other hand, buildings with seismic isolation devices have been devised in buildings (see, for example, Patent Document 2). The device described in Patent Document 2 is configured such that the viscous damping constant of the damper device is variable. This damper device has a damping structure that can efficiently absorb vibration energy generated in a building body due to an earthquake.

  FIG. 7 shows an example of a conventional quay crane 1X in which the seismic isolation device 10 is installed. The quay crane 1 </ b> X is provided with a seismic isolation device 10 made of an isolator made of, for example, laminated rubber between the traveling device 2 and the leg structure 3.

  The leg structure includes a sea-side leg 20a and a land-side leg 20b, a portal tie beam 29 that is a horizontal member connecting the legs, and a mast 24 extending above the sea-side leg 20a. Further, the leg structure 3 has a sea side sill beam 21a, a land side sill beam 21b, a sea side tie beam 22a, and a land side tie beam 22b in a direction parallel to the quay 5 (from the front side to the back side in FIG. 7). doing. Furthermore, it has a diagonal member 23 for connecting the sea side leg 20a, the land side leg 20b or the land side tie beam 22b, a mast 24, and a mast support diagonal member 25 for connecting the girder 27 or the land side tie beam 22b. In addition, the leg structure 3 has a boom 26 and a girder 27 on the upper side.

  The trolley 6 travels along the boom 26 and the girder 27 and is configured to handle the container 41. Note that 4 indicates a machine room of the crane 1X, and 40 indicates a container ship.

  FIG. 8 shows a model of the seismic isolation structure of the quay crane 1X. FIG. 8A shows a vibration analysis model of the quay crane 1X at the normal time of carrying out container handling work or the like. This model shows a state in which a mass point m0, which is the center of gravity of the quay crane 1X, is supported on the ground surface (quay) 5 via a seismic isolation device 10. The seismic isolation device 10 is shown as a combination of a spring mechanism 14 and a damper mechanism 15. Further, the mass body in the quay crane 1X is modeled as a mass point m0 in the vibration analysis model.

  FIG. 8B shows a mode (primary vibration mode) in which earthquake motion is applied to the model of the quay crane 1X and the mass m0 vibrates. Due to the earthquake motion, a force in the sea-land direction (left-right direction in FIG. 8) is generated on the crane 1X. The seismic isolation device 10 acts on this force, and the amplitude S of the mass point m0 can be suppressed. Moreover, the damper mechanism 15 can also be made into a vibration suppression structure as an energy absorption structure. With this vibration damping structure, the energy that the mass point m0 amplifies can be absorbed, and the amplitude S of the mass point m0 can be attenuated.

  In recent years, quay cranes are required to cope with large-scale earthquakes. When receiving a large-scale ground motion with the current seismic isolation device arrangement as shown in FIG. 7, it is required to absorb a horizontal deformation of about ± 1000 mm in the sea-land direction. In the future, horizontal deformation to be absorbed may increase, for example, about ± 2000 mm in the sea-land direction. However, conventional seismic isolation devices have a seismic isolation stroke of only about ± 300 mm. For this reason, when a large-scale earthquake occurs, the seismic isolation device reaches the stroke limit, which is the same as when the seismic isolation device is not installed, and there is a risk of accidents such as a crane falling or buckling.

JP-A-2005-75608 JP 2009-41337 A

  This invention is made | formed in view of said problem, The objective is to provide the crane which has the seismic isolation structure and damping structure corresponding to a large-scale earthquake. That is, it is to provide a crane capable of seismic isolation and vibration control with respect to the periodic characteristics of any seismic motion.

  In order to achieve the above object, a quay crane according to the present invention is a quay crane having a leg structure and a traveling device, wherein the quay crane can at least be regarded as a mass point in a vibration analysis model. A first seismic isolation device is installed between the ground surface and the first mass body, and a second seismic isolation device is installed between the first mass body and the second mass body. And

  With this configuration, the crane has two or more mass points (mass bodies) and constructs a multi-mass system model that connects the mass points with a seismic isolation device. Seismic isolation and vibration control. In other words, the vibration of the crane due to the earthquake motion can be suppressed since the resonance state is hardly brought about by the earthquake motion.

  In the above quay crane, the leg structure is divided into at least an upper structure and a lower structure, a first seismic isolation device is installed between the traveling device and the lower structure, and the lower structure and the upper structure A second seismic isolation device is installed between the structures.

  With this configuration, the first seismic isolation device suppresses vibrations transmitted from the ground surface to the leg structure, and the second seismic isolation device divides the leg structure into two mass points (mass bodies). Resonance can be prevented.

  In the above quay crane, the leg structure has at least a sea side leg, a land side leg, a boom and a girder, and the lower structure has at least the land side leg or the sea side leg, The superstructure has at least the sea side leg or the land side leg, and a part of the seismic isolation device is installed on the side of the sea side leg or the land side leg.

  Even if it is a case where a flexural vibration generate | occur | produces in the edge part of a sea side leg or a land side leg by this structure as a cause of an earthquake motion, the influence which this flexural vibration has on a seismic isolation apparatus can be suppressed. Therefore, the crane can obtain a sufficient seismic isolation and vibration control effect even for a large-scale earthquake.

In the above quay crane, the seismic isolation device is constituted by a spring mechanism and a damper mechanism, and the swinging of the seismic isolation device is fixed by a fixture under a first condition, and at least the spring mechanism under a second condition. The swing constant of the seismic isolation device is controlled by controlling the spring constant or the viscosity constant of the damper mechanism.

  With this configuration, the crane can be actively controlled, and the vibration control effect can be improved. That is, since the vibration (displacement amount) of the seismic isolation device can be controlled so as to cancel the vibration of the crane due to the earthquake motion, the vibration of the crane can be positively attenuated. The first condition is assumed to be a normal time when the crane performs a cargo handling operation of the container, and the second condition is assumed to be an earthquake.

  In the quay crane described above, a hydraulic damper with a lock function is installed in the seismic isolation device, and the hydraulic damper with a lock function is slidable on a shaft having a variable flow piston at an end and the variable flow piston inside. And having a casing filled with fluid, and under a first condition, a through hole formed in the variable flow piston is closed, the shaft is fixed to the casing, and the seismic isolation Control is performed to prohibit the swinging of the device, and under the second condition, a through hole formed in the variable flow piston is communicated so that the shaft is slidable with respect to the casing. It is characterized by performing control that allows movement freely.

  With this configuration, the timing at which the crane's seismic isolation device starts operating can be precisely controlled. In other words, it is possible to control the seismic isolation device to operate quickly when an earthquake motion having a magnitude exceeding a preset value occurs. Therefore, a reliable and precise seismic isolation effect can be obtained.

  In order to achieve the above object, a quay crane control method according to the present invention is a quay crane having a leg structure and a traveling device, wherein the quay crane can at least be regarded as a mass point in a vibration analysis model, and A quay crane having a second mass body, wherein a first seismic isolation device is installed between the ground surface and the first mass point, and a second seismic isolation device is installed between the first mass point and the second mass point. In the control method, the seismic isolation device is configured by a spring mechanism and a damper mechanism. Under the first condition, the swinging of the seismic isolation device is controlled by a fixture, and the second condition Below, it is characterized by controlling the oscillation of the seismic isolation device by controlling at least the spring constant of the spring mechanism or the viscosity constant of the damper mechanism. With this configuration, it is possible to obtain the same effects as the quay crane described above.

  Further, in the aforementioned quay crane, the leg structure is divided into at least an upper structure, an intermediate structure, and a lower structure, and a first seismic isolation device is installed between the traveling device and the lower structure, A second seismic isolation device may be installed between the lower structure and the intermediate structure, and a third seismic isolation device may be installed between the intermediate structure and the upper structure.

  With this configuration, the crane has three mass points (mass bodies) and constructs a three-mass system model that connects the mass points with a seismic isolation device. Seismic isolation and vibration control can be applied to the periodic characteristics.

  According to the crane according to the present invention, it is possible to obtain a seismic isolation and vibration control structure corresponding to a large-scale earthquake motion. That is, the crane is not in a resonance state with respect to the periodic characteristics of all ground motions, and the seismic isolation and damping effect can be obtained efficiently.

It is the figure which showed the outline | summary of the crane of embodiment which concerns on this invention. It is the figure which showed the model for vibration analysis of the crane of embodiment which concerns on this invention. It is the figure which showed the model for vibration analysis of the crane of embodiment which concerns on this invention. It is the figure which showed the outline | summary of the crane of different embodiment which concerns on this invention. It is the elements on larger scale of the crane of different embodiment which concerns on this invention. It is the figure which showed the hydraulic damper with the locking function of the crane of embodiment which concerns on this invention. It is the figure which showed the outline | summary of the crane with the conventional seismic isolation mechanism. It is the figure which showed the model for vibration analysis of the crane which has the conventional seismic isolation mechanism.

  Hereinafter, a crane according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a quay crane 1 in which a leg structure 3 is divided into three and a seismic isolation device is installed on the boundary surface. The leg structure 3 is divided into a lower structure, an intermediate structure, and an upper structure, and the first seismic isolation device 11, the second seismic isolation device 12, and the third seismic isolation device 13 are provided at the respective boundaries. It is installed. A traveling device 2 is arranged below the first seismic isolation device 11.

  Between the first seismic isolation device 11 and the second seismic isolation device 12, a sea side sill beam 21a, a land side sill beam 21b, and a portal tie beam 29 are arranged (lower structure). Between the second seismic isolation device 12 and the third seismic isolation device 13, the sea side leg 20a, the land side leg 20b, and the diagonal member 23 are arranged (intermediate structure). The sea side tie beam 22a, the land side tie beam 22b, the mast 24, the mast support diagonal member 25, the boom 26, the girder 27, and the machine room 4 are disposed in the upper part of the third seismic isolation device 13 (upper structure). .

  In addition, although it is desirable to use the isolator comprised with laminated rubber for a seismic isolation apparatus, other seismic isolation apparatuses can also be utilized. For example, a seismic isolation device in which a horizontal slider mechanism, a spring mechanism, a damper mechanism or the like is used alone or in combination can be used.

  FIG. 2 shows a vibration analysis model of the quay crane 1 shown in FIG. In this vibration analysis model, the center of gravity of the lower structure, the intermediate structure, and the upper structure (mass body) is represented as a first mass point m1, a second mass point m2, and a third mass point m3. Further, the respective mass points (mass bodies) are connected via the first seismic isolation device 11, the second seismic isolation device 12, and the third seismic isolation device 13. The seismic isolation devices 11, 12, and 13 are represented by a combination of a spring mechanism 14 and a damper mechanism 15. Further, the heights h1, h2, and h3 indicate the heights from the ground surface (quay) 5 to the respective mass points m1, m2, and m3.

  Next, the operation of the seismic isolation device in the crane 1 will be described. In a normal time (first condition) in which a container is unloaded, the seismic isolation devices 11, 12, and 13 of the crane 1 are fixed with a fixing tool such as a shear pin to be in a rigid state. When an earthquake occurs (second condition), the shear pin or the like is broken and the seismic isolation device acts to suppress and attenuate the vibration generated in the crane 1.

  FIG. 3 shows how the crane 1 vibration analysis model vibrates. FIG. 3A shows a normal state in which the crane 1 handles the container 41 and the like. FIG. 3B shows a state in which an earthquake occurs and the mode in which the position of the third mass point m3 stops with respect to the ground surface 5 and the first mass point m1 and the second mass point m2 vibrate in opposite directions. FIG. 3C shows a state at the time of occurrence of the earthquake, in which the position of the second mass point m2 stops with respect to the ground surface 5, and the first mass point m1 and the third mass point m3 vibrate in opposite directions. These vibration modes are determined using the input earthquake motion, the weight of each mass point m, the height h from the ground surface to each mass point, the spring constant k of the spring mechanism 14 and the viscosity constant c of the damper mechanism 15 as parameters. Is done. Therefore, if the vibration mode of the crane 1 shown in FIGS. 3B and 3C is set so as to be a low-order crane natural vibration mode, the movements of the mass points m1, m2, and m3 cancel each other out of the vibration caused by the earthquake motion, and the entire crane Can be suppressed.

  Here, it is assumed that the seismic isolation devices 11, 12, and 13 are passively controlled. On the other hand, the seismic isolation device may be configured as active control so as to actively attenuate the vibration of the crane 1. That is, when an earthquake occurs, control may be performed to change the spring constant k or the viscosity constant c, which is a parameter for determining the vibration mode, and the swing of the seismic isolation device may be positively controlled. Further, in fixing and releasing the seismic isolation device, a hydraulic drive lock pin, an electric drive lock pin, a hydraulic damper with a lock function, or the like may be used as a fixture instead of the shear pin.

  Next, vibration control of the crane 1 will be described. First, the case where the seismic isolation devices 11, 12, and 13 are set to passive control will be described. When the seismic isolation device is passively controlled, the crane 1 is designed using the parameters (mass m, height h, spring constant k, viscosity constant c) constituting the crane 1 as variables. For example, it is desirable to design such that the vibration of the crane 1 does not diverge with respect to a presumed earthquake motion and is in the vibration mode shown in FIG. That is, it is desirable to design the vibration mode of FIG. 3B or C to be a low-order crane natural vibration mode.

  During normal handling of containers, etc., the seismic isolation devices 11, 12, 13 of the crane 1 are fixed with shear pins, hydraulic drive lock pins, electric drive lock pins, hydraulic dampers with a lock function, etc. Yes. When an earthquake occurs, the seismic isolation device acts by breaking the shear pin, etc., and vibrates in the mode shown in FIGS. 3B and 3C or in a state where they are overlapped. When a hydraulic drive lock pin, an electric drive lock pin, a hydraulic damper with a lock function, or the like is used, an earthquake occurrence is detected by a sensor or the like to open the seismic isolation device.

  Next, the case where the seismic isolation devices 11, 12, and 13 are set to active control will be described. When the seismic isolation device is active control, the crane 1 is designed with each parameter constituting the crane 1 as a variable. Furthermore, the spring constant k and the viscosity constant c are made variable so that they can be positively controlled when an earthquake occurs. When an earthquake occurs, the spring constant k of the spring mechanism 14 or the viscosity constant c of the damper mechanism 15 is controlled to control the crane 1 to vibrate in an arbitrary vibration mode.

  With the above configuration, the following operational effects can be obtained. 1stly, the structure which the crane 1 has two or more mass points m (m1, m2, m3 etc.) can acquire sufficient seismic isolation and a damping effect also with respect to a large-scale earthquake. In other words, two or more mass points m connected via a seismic isolation device are unlikely to be in a divergent resonance state with respect to seismic motion generated on the ground surface (quay) 5. Vibration can be suppressed.

  Secondly, the conventional seismic isolation device can be used to configure the crane 1 that can handle large-scale earthquakes, so that it is possible to prevent a significant increase in weight of the crane 1 and an increase in cost due to the implementation of earthquake countermeasures. it can. That is, even with a seismic isolation device having a seismic isolation stroke of about ± 300 mm, the above-described configuration can provide seismic isolation and damping effects for ± 1000 mm earthquake motions and more.

  Third, in the design stage of the crane 1, the weight of each mass m, the height h from the ground surface (quay) 5 to each mass m, the spring constant k of the spring mechanism 14, according to the earthquake motion assumed in advance. The viscosity constant c of the damper mechanism 15 can be changed. Therefore, for example, even when an earthquake that continuously releases high energy over a long period of 300 seconds is assumed, sufficient seismic isolation and vibration control effects can be obtained. In particular, sufficient seismic isolation and vibration control effects can be obtained without causing the crane 1 to diverge, even for long-period ground motions that could not be dealt with conventionally.

  Fourth, when the seismic isolation device is active control, it can be controlled to effectively attenuate the vibration of the crane 1 with respect to seismic motion of any frequency. That is, while the crane 1 is vibrating due to the earthquake, for example, an arbitrary vibration mode can be set by controlling the viscosity constant c of the damper mechanism 15.

  Specifically, for example, the mass point m3 above the crane 1 is controlled to vibrate in the direction opposite to the direction of the earthquake motion. By this control, the mass point m3 can be used as a damping mass (a weight for canceling the vibration) for the crane 1.

  Fifth, when using a hydraulic drive lock pin, an electric drive lock pin, or a hydraulic damper with a lock function instead of a shear pin for fixing and opening the seismic isolation device, It can be selectively controlled. That is, it is possible to intentionally create a seismic isolation device that does not open when an earthquake occurs and to control the vibration mode.

  Specifically, while seismic motion continues, the seismic isolation device can be fixed and released to control the vibration mode. For example, in the initial stage of earthquake occurrence, the first seismic isolation device 11 and the second seismic isolation device 12 are opened, and the third seismic isolation device 13 is fixed. Thereafter, it is possible to perform control to open all the seismic isolation devices.

  Moreover, it is possible to determine whether the seismic isolation device is fixed or released from the magnitude of the amplitude of the ground motion, and to control the vibration mode. Specifically, for example, when the width of the vibration of the earthquake motion is ± 300 mm or less, only the first seismic isolation device 11 is opened and the rest is fixed. When the width of the vibration of the earthquake motion is ± 300 mm to ± 500 mm, the first seismic isolation device 11 and the second seismic isolation device 12 are opened, and the third seismic isolation device 13 is fixed. When the width of the vibration of seismic motion is ± 500 mm or more, control such as opening all seismic isolation devices can be performed.

  In the vibration mode control of the crane 1, the seismic isolation device may be actively controlled based on information such as earthquake bulletin. Specifically, first, the amplitude of seismic motion is acquired from information received wirelessly. The seismic isolation device to be opened is determined so as to vibrate in an arbitrary vibration mode (such as the vibration mode in FIG. 3B or C) against this seismic motion, and the spring constant k of the spring mechanism 14 and the viscosity constant c of the damper mechanism 15 are determined. Etc. control is started. Next, the seismic isolation device to be opened may be changed in accordance with changes in seismic motion to control the spring constant k and the viscosity constant c.

  FIG. 4 shows a quay crane 1A according to a different embodiment of the present invention. The crane 1A divides the leg structure 3 into two parts, a lower structure and an upper structure, and a first seismic isolation device 11 is provided between the traveling device 2 and the lower structure, and the lower structure and the upper structure. The second seismic isolation device 12 and the additional seismic isolation device 16 are installed.

  Between the first seismic isolation device 11, the second seismic isolation device 12 and the additional seismic isolation device 16, the sea side sill beam 21a, the land side sill beam 21b, the land side leg 20b, the land side tie beam 22b, the machine room 4 and the portal. A tie beam 29 is arranged (substructure).

  The upper part of the second seismic isolation device 12 and the additional seismic isolation device 16 has an additional beam 17, a sea side leg 20 a, a sea side tie beam 22 a, a diagonal material 23, a mast 24, a mast support diagonal material 25, a boom 26, and a girder 27. (Superstructure).

In FIG. 5, the enlarged view centering on the additional seismic isolation apparatus 16 is shown. The additional seismic isolation device 16 is placed on a gantry 18 installed on the side of the land-side leg 20b. An additional beam 17 is fixed on the additional seismic isolation device 16. The additional beam 17 and the mast support diagonal member 25 are connected to a girder 27. Further, the diagonal member 23 is fixed to the additional beam 17. On the other hand, the lower structure side has the land side leg 20b and the machine room 4 installed in the upper part via the land side tie beam 22b.

  With the above configuration, the following operational effects can be obtained. First, the crane 1A can obtain sufficient seismic isolation and vibration control effects even for a large-scale earthquake due to the configuration having two mass points. Secondly, since the main beam members (lower structures) constituting the leg structure 3 form a portal or triangular structure, it is possible to increase the flexural rigidity. Therefore, it is possible to avoid a situation where the seismic isolation stroke generated in the second seismic isolation device 12 and the additional seismic isolation device 16 is offset by the deflection deformation of the beam member.

  As described above, the case where the number of mass points of the crane 1 is three and the case where the number of mass points is two has been described. However, the present invention is not limited to these. Can be obtained. Specifically, for example, the boom 25 and the girder 27 suspended from the sea-side tie beam 22a and the land-side tie beam 22b can be configured to be suspended via a seismic isolation mechanism.

  In FIG. 6, the example of the hydraulic damper 31 with a lock function installed in the seismic isolation apparatus 11, 12, 13 is shown. This hydraulic damper 31 with a lock function is installed instead of the shear pin installed in the seismic isolation device. As shown to FIG. 6A, this hydraulic damper 31 with a lock function is installed so that the both ends of a seismic isolation apparatus may be connected and fixed. Here, the seismic isolation device includes a laminated rubber 36 in which steel plates and rubber are laminated, and a link mechanism 37. The link mechanism 37 is configured to restrain the swing of the laminated rubber 36 in the sea-land direction (the left-right direction in FIG. 6).

FIG. 6B shows a partial cross-sectional view of the hydraulic damper 31 with a lock function. The hydraulic damper 31 with a lock function includes a double tubular shaft 32 having a variable flow rate piston 33 at an end, and a casing 34 filled with a fluid such as oil. The variable flow rate piston 33 has a through hole 35, and is configured so that the opening area of the through hole 35 can be controlled.

  Specifically, the variable flow piston 33 is configured by stacking disk-shaped members each having a through hole 35. One of the disk-shaped members is rotated, and the through-holes 35 of the disk-shaped member can be communicated or closed by this rotation.

  The rotation of the variable flow piston 33 may be controlled by installing power such as a motor. Moreover, you may install combining elastic members, such as a spring, and fixing members, such as an electromagnet. That is, normally, the variable flow rate piston 33 is in a state in which the through hole 35 is closed against the restoring force of the elastic body, and the piston 33 is fixed by the fixing member. And when an earthquake occurs, you may comprise so that fixation by a fixing member may be cancelled | released and the piston 33 may rotate so that the through-hole 35 may be connected by an elastic body.

  Next, the operation of the hydraulic damper 31 with a lock function will be described. During normal operation (first condition), the through hole 35 of the variable flow rate piston 33 is closed, and control is performed so that the filled fluid does not move in the casing 34. By this control, the shaft 32 is fixed to the casing 34, so that the seismic isolation device is fixed (rigid state).

When an earthquake occurs (second condition), the disk-shaped member is rotated to communicate with the through hole 35 of the variable flow rate piston 33. In the casing 34, the filled fluid is controlled to move freely through the through hole 35. By this control, the shaft 32 becomes slidable with respect to the casing 34, so that the seismic isolation device can swing and exhibits its effect.

  With the configuration using the hydraulic damper 31 with the lock function, the seismic isolation device of the crane 1 can be appropriately operated. In the past, the operation of the seismic isolation device was started by breaking the shear pin, but it was difficult to control the breaking force of the shear pin. With respect to this shear pin, the hydraulic damper 31 with a lock function can control the timing at which the seismic isolation device operates, so that a reliable and precise seismic isolation and damping effect can be obtained.

  Here, you may comprise so that control of the variable flow piston 33 may be performed actively. That is, the opening area of the through hole 35 is controlled in real time based on the amount of displacement of the seismic isolation device. With this configuration, since the sliding resistance of the variable flow piston 33 in the hydraulic damper 31 with a lock function can be controlled, the damping characteristic of the seismic isolation device can be controlled.

  From the above, since the seismic isolation and vibration control effects of the cranes 1 and 1A can be improved, the earthquake resistance against a large-scale earthquake can be improved.

1 Crane (quay crane)
2 Traveling equipment 3 Leg structure 5 Ground surface (quay)
11 First Seismic Isolation Device 12 Second Seismic Isolation Device 13 Third Seismic Isolation Device 14 Spring Mechanism 15 Damper Mechanism 20a Sea Side Leg 20b Land Side Leg 26 Boom 27 Girder 31 Hydraulic Damper 32 with Lock Function Shaft 33 Variable Flow Piston 34 Casing 35 Through-hole k Spring constant c Viscosity constant m1 First mass point m2 Second mass point m3 Third mass point

Claims (4)

In a quay crane having a pair of sea-side legs, a pair of land-side legs, a leg structure having a boom and a girder extending in the sea-land direction, and a traveling device installed at the lower end of the leg structure,
The leg structure is divided into at least an upper structure and a lower structure, a first seismic isolation device is installed between the traveling device and the lower structure, and between the lower structure and the upper structure. Installed a second seismic isolation device,
The seismic isolation device is composed of a spring mechanism and a damper mechanism with its swinging direction being restrained in the sea-land direction ,
A sea tie beam extending in the traveling direction of the traveling device to connect the upper portions of the pair of sea side legs; and a pair of land sides extending in the traveling direction of the traveling device. A land-side tie beam connecting upper portions of the legs, and the girder extends from the sea-side tie beam to the land-side tie beam ,
The lower structure extends in the traveling direction and connects the lower sill beams connecting the lower portions of the pair of land-side legs, and the lower structure extends in the traveling direction and connects the lower portions of the pair of sea-side legs. A quay crane comprising: a sea-side sill beam, and a portal tie beam that extends in a horizontal direction perpendicular to the traveling direction and connects the sea-side leg and the land-side leg. In a quay crane having a pair of sea-side legs, a pair of land-side legs, a leg structure having a boom and a girder extending in the sea-land direction, and a traveling device installed at the lower end of the leg structure,
The leg structure is divided into an upper structure, an intermediate structure, and a lower structure, and a first seismic isolation device is installed between the traveling device and the lower structure, and the lower structure and the intermediate structure A second seismic isolation device is installed between the intermediate structure and the upper structure, and a third seismic isolation device is installed between the intermediate structure and the upper structure,
The seismic isolation device is composed of a spring mechanism and a damper mechanism with its swinging direction being restrained in the sea-land direction ,
A sea tie beam extending in the traveling direction of the traveling device to connect the upper portions of the pair of sea side legs; and a pair of land sides extending in the traveling direction of the traveling device. A land-side tie beam connecting upper portions of the legs, and the girder extends from the sea-side tie beam to the land-side tie beam ,
The intermediate structure includes a diagonal member connecting the lower part of the sea side leg and the upper part of the land side leg facing each other,
The lower structure extends in the traveling direction and connects the lower sill beams connecting the lower portions of the pair of land-side legs, and the lower structure extends in the traveling direction and connects the lower portions of the pair of sea-side legs. A quay crane comprising: a sea-side sill beam, and a portal tie beam that extends in a horizontal direction perpendicular to the traveling direction and connects the sea-side leg and the land-side leg. Having a fixture for fixing and opening the seismic isolation device;
The quay crane according to claim 1 or 2, wherein the fixture has a configuration for controlling a vibration mode of the quay crane by controlling fixation and release of the seismic isolation device while seismic motion continues.   4. The vibration mode of the quay crane is controlled by controlling a spring constant of the spring mechanism or a viscosity constant of the damper mechanism while the quay crane vibrates due to an earthquake. Wharf crane as described in

Images