CN219342880U

CN219342880U - High mound stable structure based on pergola climbs

Info

Publication number: CN219342880U
Application number: CN202320739693.0U
Authority: CN
Inventors: 张琴光; 皮广兵
Original assignee: Individual
Current assignee: Individual
Priority date: 2023-04-06
Filing date: 2023-04-06
Publication date: 2023-07-14
Anticipated expiration: 2033-04-06

Abstract

The utility model discloses a high pier stabilizing structure based on flower frame climbing, which comprises a flower frame encircling the periphery of high pier concrete, wherein pier columns are arranged at the upper end of the high pier concrete, a construction platform is arranged on the flower frame, and the construction platform is used for installing a pouring template; the flower stand is provided with a cross frame, the cross frame is connected with the pier column through a fastener, and the flower stand transmits load to the pier column through the cross frame; lifting equipment is arranged on the high pier concrete, a support frame is arranged on the flower stand, and the lifting equipment is used for applying thrust to the support frame to enable the flower stand and the cross frame to move upwards; the side wall of the flower stand is provided with a wheel set frame, the front end of the wheel set frame is provided with a rubber wheel, and the rubber wheel is used for abutting against the outer wall of the high pier concrete; in order to expect to improve the current hydraulic system and climb in-process, cancel the guide rail structure after, its pergola climb in-process easily appear the problem of lateral displacement.

Description

High mound stable structure based on pergola climbs

Technical Field

The utility model relates to synchronous lifting of a flower stand and a well frame, in particular to a high pier stabilizing structure based on climbing of the flower stand.

Background

The high piers generally employ large steel members due to their relatively high support requirements. Therefore, in the construction of high piers, a flower stand is generally used as an external construction area, and since the flower stand needs to be hung, it is very important to ensure the stability of the flower stand; at present, when the flower stand is constructed, stronger support is required, and the flower stand is usually fixed on a support structure of a high pier, and connection and fixation can be realized in a temporary bolt mode when necessary. Its pergola climbs, and current common mode sets up temporary guide rail on the high mound, sets up temporary slider structure on the pergola to utilize the cooperation mode of guide rail and slider to ensure that the lift of pergola is stable, and effectually avoid the pergola to appear the skew in the lift in-process. But this kind of structure construction intensity is high, and needs to guarantee the stability of guide rail in vertical direction to make the precision requirement relatively higher in the work progress, even need to beat the plumb line.

The high pier construction structures developed at present mainly use pergola and well word frame to climb simultaneously, and the hydraulic system is mainly used to upwards advance pergola and well word frame in the climbing process to reduce loaded down with trivial details guide rail installation, only need hydraulic system be in relative vertical state, thereby make pergola structure can vertically climb relative original position.

When the flower stand climbs, the flower stand is usually required to be in a relatively balanced state. Since the flower stand structure is not absolutely symmetrical, the perfect symmetry of the distributed load cannot be ensured, so that the flower stand may be inclined. Although the current physical structure has certain deviation rectifying performance on unbalanced load, the stability of the pergola climbing can be influenced under external influences such as weather, wind speed, topography and other environmental factors, so that lateral displacement occurs in the pergola climbing process, and construction safety is influenced.

Disclosure of Invention

The utility model aims to provide a high pier stabilizing structure based on flower frame climbing, which aims to solve the problem that lateral displacement is easy to occur in the flower frame climbing process after a guide rail structure is cancelled in the climbing process of the existing hydraulic system.

In order to solve the technical problems, the utility model adopts the following technical scheme:

the high pier stabilizing structure based on the pergola climbing comprises a pergola encircling the periphery of high pier concrete, wherein pier columns are arranged at the upper end of the high pier concrete, a construction platform is arranged on the pergola, and the construction platform is used for installing a pouring template; the flower stand is provided with a cross frame, the cross frame is connected with the pier column through a fastener, and the flower stand transmits load to the pier column through the cross frame; lifting equipment is arranged on the high pier concrete, a support frame is arranged on the flower stand, and the lifting equipment is used for applying thrust to the support frame to enable the flower stand and the cross frame to move upwards; the side wall of the flower stand is provided with a wheel set frame, the front end of the wheel set frame is provided with a rubber wheel, and the rubber wheel is used for abutting against the outer wall of the high pier concrete.

Preferably, the wheel sets are distributed around the high pier concrete, and the rubber wheels are used for moving on the side wall of the high pier concrete and restraining the flower frames.

Preferably, the lifting device comprises a first carrier, a lifting oil cylinder is arranged on the first carrier, a first lock is arranged at the lower end of the first carrier, the first lock is locked on the high pier concrete, the upper end of the lifting oil cylinder is connected with a supporting frame, and a third lock is arranged at the lower end of the supporting frame.

The lifting device comprises a second carrier, wherein a second lock is arranged at the lower end of the second carrier, the first carrier and the second carrier are both connected with a lifting cylinder, and the lifting cylinder is locked on high pier concrete through the first lock and the second lock.

The further technical scheme is that the lifting cylinders are multiple, and the lifting cylinders are arranged on the first carrier and the second carrier.

Preferably, the lifting device comprises a bearing frame and a jack, wherein the jack is arranged on the bearing frame, the bearing frame is used for connecting an embedded part on high pier concrete, the upper end of the jack is connected with the flower frame and the support frame, and the flower frame and the well frame are driven by the jack to move upwards.

Preferably, the wheel set frame is located above the support frame and below the lifting device, and the distance between the wheel set frame and the lifting device is greater than the upward movement stroke of the support frame.

Compared with the prior art, the utility model has the beneficial effects that at least one of the following is adopted:

according to the utility model, the flower stand is used as a supporting point on the supporting frame, the flower stand can be fixed on the high pier concrete through the supporting frame, the flower stand is also fixed by the cross frame, so that the stability of the flower stand in a non-lifting state on the high pier concrete is ensured, when the flower stand needs to climb, the cross frame and the flower stand need to synchronously lift, at the moment, thrust is applied in the vertical direction through lifting equipment, the flower stand is restrained at the position relative to the high pier concrete by using the wheel set frame, the wheel set frame adopts rubber wheels to reduce friction coefficient, and the surface of the high pier concrete is not broken in the climbing process of the flower stand, so that the climbing stability is maintained. Secondly, the lifting device is mainly a lifting oil cylinder, and the oil cylinder is fixedly sleeved on the high pier concrete by utilizing a third hoop on the first carrier, so that when the third hoop on the support frame is released, the lifting oil cylinder can apply thrust to the support frame on the high pier concrete, and the flower stand moves upwards. Because the locking structure needs to be installed on the high pier concrete, when the rubber wheel is used, through the arrangement of the position, the flower stand is restrained, the contact locking structure is avoided, and accordingly climbing relativity is guaranteed.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model.

FIG. 2 is a schematic diagram of the operation of the rubber wheel of the present utility model.

Fig. 3 is a schematic view of a casting form installation of the present utility model.

FIG. 4 is a schematic view of a hoist link of the present utility model

Reference numerals illustrate:

the hydraulic system comprises a 1-flower stand, a 2-high pier concrete, a 3-supporting frame, a 4-lifting oil cylinder, a 5-first carrier, a 6-second carrier, a 7-transfer platform, an 8-construction platform, a 9-cross frame, an 11-wheel set frame, a 12-rubber wheel, a 13-pier column, a 301-third lock, a 501-first lock, a 601-second lock, a 701-walking track, a 702-winch, an A-pouring template and a B-pushing mechanism.

Detailed Description

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

Referring to fig. 1 and 2, an embodiment of the utility model is a high pier stabilizing structure based on flower stand climbing, which comprises a flower stand 1 surrounding the periphery of a high pier concrete 2, wherein the flower stand 1 is built by an existing steel frame, and the flower stand 1 is built by triangular supporting structures in the longitudinal direction and the transverse direction, so that the flower stand 1 has higher stability, and local collapse and fracture risks are avoided. Above-mentioned pergola 1 encircles around high mound concrete 2 for pergola 1 can be higher around high mound concrete 2 and keep sufficient clearance distance through pergola 1 in horizontal and longitudinal distribution, so that the staff is under construction high mound concrete 2, and avoid appearing the collision risk in climbing the in-process.

The upper end of the high pier concrete 2 is provided with pier columns 13, wherein the pier columns 13 are steel bar structures buried on the high pier concrete 2. A construction platform 8 is arranged on the flower stand 1, and the construction platform 8 is used for installing a pouring template A; the construction platform 8 surrounds the high pier concrete 2, and for better demolding of the pouring template A, the construction platform 8 is provided with a corresponding pushing-out mechanism, and the pouring template A moves through the pushing-out mechanism, so that the pouring template A can be conveniently close to/far away from the high pier concrete 2.

The flower stand 1 is provided with a groined frame 9, the groined frame 9 is connected with the pier 13 through a fastener, and the flower stand 1 transmits load to the pier 13 through the groined frame 9; the flower stand 1 is provided with a cross frame 9, and the cross frame 9 is locked on pier posts 13 at the upper part of the high pier concrete 2 through fasteners. The well frame 9 adopts the existing steel frame structure, the well frame is mainly used for fixing pier studs 13 on the high pier concrete 2, the well frame 9 can form support through the pier studs, and the well frame 9 can be further provided with a crane hoist to form support on a pouring template in the vertical direction. The end of the cross frame 9 is connected with the flower frame 1, and when the flower frame 1 needs to climb, the connection part of the cross frame 9 and the pier 13 needs to be released, so that the cross frame 9 and the flower frame 1 climb synchronously.

The high pier concrete 2 is provided with lifting equipment, wherein the lifting equipment is mainly used for applying thrust to the flower stand 1, so that when the flower stand 1 and the high pier concrete 2 are not fixed, the flower stand is lifted through the lifting equipment; in the process, as the flower stand 1 needs to be released on the high pier concrete 2, the lifting equipment bears relatively large load in the vertical direction, and considering that the flower stand 1 is not in a relatively balanced state, the flower stand 1 structure at the moment can possibly generate lateral stress under the influence of external environment.

The deviation can be reduced through the rigid structure of the lifting equipment and the flower stand 1, namely, the flower stand 1 is provided with the support frame 3, and the lifting equipment is used for applying thrust to the support frame 3 to enable the flower stand 1 and the cross frame 9 to move upwards; so that the sideways forces are directly transferred by the support frame 3 to the lifting device.

Considering that the moment of the lifting device changes in the lifting process, in order to better reduce the lateral tension of the lifting device, the side wall of the flower stand 1 is provided with a wheel set frame 11, the front end of the wheel set frame 11 is provided with a rubber wheel 12, and the rubber wheel 12 is used for abutting against the outer wall of the high pier concrete 2.

The wheel set frame 11 surrounds the high pier concrete 2 on the flower frame 1, so that after the flower frame 1 receives lateral tension, the tension is transmitted to the lifting device through the support frame 3 and also can be transmitted to the high pier concrete 2 through the wheel set frame 11, and because the high pier concrete 2 is of a concrete structure, under the condition that the rubber wheels 12 serve as buffer units, the lateral load of the flower frame 1 can be transmitted to the high pier concrete 2. Thereby reducing the excessive load influence to which the lifting device is subjected in the lateral direction. Is favorable for improving climbing stability.

In order to ensure the stability of the wheel set frame 11, the wheel set frame 11 on the flower stand 1 is generally fixed by bolts, the wheel set frame 11 is provided with a contact surface corresponding to the flower stand 1, the contact surface and the flower stand 1 are fixed by the existing bolts, and the stability of the wheel set frame 11 after being installed is checked regularly, so that the wheel set frame is matched with the rubber wheels 12 to support the flower stand 1 effectively in the climbing process of the flower stand 1. The lifting mechanical energy auxiliary device is prevented from being arranged beside the flower stand 1, so that the flower stand 1 is not deviated from a preset track in the lifting process, the lifting mechanical energy auxiliary device can be used for reducing the arrangement of the lifting machinery, and the lifting mechanical energy auxiliary device is suitable for convenient construction in various scenes.

It should be noted that, in the manner of using the rubber wheel 12 for position constraint, for convenience and intellectualization of construction, the existing control system, monitoring system, position sensor, total station and other modern technical equipment can be adapted to the flower stand 1. The pier column plane control measurement can be carried out by adopting a three-dimensional coordinate method, a total station is erected to a bridge construction control point, the three-dimensional coordinates of four corner points of the pier column are directly measured, and the three-dimensional coordinates are checked by using a steel ruler on site, so that the accuracy of the plane position of the pier column is ensured, the pier column elevation is controlled by utilizing the total station, and the high pier check can be carried out by measuring by using a level gauge. And stopping construction for safety inspection in the climbing process of the flower stand 1 so as to ensure the safety and stability of the flower stand in the climbing process. Through current monitored control system, can real-time supervision pergola 1 is last rubber wheel 12 state to if install current position sensor on the pergola 1, can cooperate the travel state of the better monitoring equipment moving track of current equipment through position sensor.

Based on the above embodiment, in another embodiment of the present utility model, the number of the wheel sets 11 is several, the wheel sets 11 are distributed around the high pier concrete 2, and the rubber wheels 12 are used for moving on the side wall of the high pier concrete 2 and restraining the flower stand 1.

The number distribution of the wheel sets 11 is used for improving load transmission, so that the deviation risk caused by local load asymmetry is improved, and the design of the rubber wheels 12 can reduce the damage risk of climbing valleys of the flower stand 1 to the surface of the high pier concrete 2.

The position of the rubber wheel 12 needs to avoid the position of the embedded part on the high pier concrete 2, so that the position of the embedded part on the high pier concrete 2 needs to avoid the upward moving track of the rubber wheel 12 in the longitudinal direction.

Based on the above embodiment, according to another embodiment of the present utility model, the lifting device includes a first carrier 5, a lifting cylinder 4 is disposed on the first carrier 5, a first lock 501 is disposed at a lower end of the first carrier 5, the first lock 501 is fixed on the high pier concrete 2, an upper end of the lifting cylinder 4 is connected to a support frame 3, and a third lock 301 is disposed at a lower end of the support frame 3.

The lifting oil cylinder 4 is provided with a first carrier 5, the first carrier 5 is of an annular structure built by a reinforced structure, the lifting oil cylinder 4 is fixed on the first carrier 5 through welding and an existing locking piece, and the lifting oil cylinder 4 is kept in a vertical state. The first carrier 5 is provided with a first lock 501, and the first lock 501 is used for locking on the high pier concrete 2; the first carrier 5 is provided with a first lock 501 with the same structure as the third lock 301, and the first lock 501 is connected with an embedded part to form a supporting point. The construction on the high pier concrete 2 is generally carried out in a sectional mode, so that the climbing distance is within the engineering design range every time, and therefore the embedded part is convenient to set on the high pier concrete 2. The upper end of the lifting oil cylinder 4 is connected with a supporting frame 3, and the lifting oil cylinder 4 applies upward thrust to the flower stand 1 through the supporting frame 3. The movable end of the lifting oil cylinder 4 is connected with the supporting frame 3, so that the supporting frame 3 can bear upward thrust of a plurality of lifting oil cylinders 4 at the same time and acts on the flower stand 1, and the flower stand 1 ascends.

When the flower stand 1 is required to be lifted, the third lock 301 on the high pier concrete 2 can be released temporarily, so that after the flower stand 1 is lifted to a designated height, the third lock 301 locks on an embedded part on the high pier concrete 2, and the third lock 301 is distributed around the high pier concrete 2 in a ring shape, so that good load support can be carried out on the flower stand 1, and the flower stand 1 can be locked and fixed.

Further, the lifting device comprises a second carrier 6, a second lock 601 is arranged at the lower end of the second carrier 6, the first carrier 5 and the second carrier 6 are both connected with the lifting cylinder 4, and the lifting cylinder 4 is locked on the high pier concrete 2 through the first lock 501 and the second lock

Wherein, through setting up second carrier 6, utilize the second on the second carrier 6 to embrace the lock 601, realize double-locking, and lift cylinder 4 carries out the multiple spot through first carrier 5 and second carrier 6 and support to be favorable to lift cylinder 4 to obtain higher bearing capacity in the vertical direction, be favorable to improving lift cylinder 4 stability on high mound concrete 2.

The second carrier 6 and the first carrier 5 are parallel to each other, and the firmness of the lifting oil cylinder 4 is ensured by using the second holding lock 601 and the third holding lock 301, so that the load can be stably transferred to the flower stand 1 when the lifting oil cylinder 4 works.

Further, the number of the lift cylinders 4 is plural, and the lift cylinders 4 are mounted on the first carrier 5 and the second carrier 6. Because the flower stand 1 has relatively large load, the flower stand is restrained by designing more lifting cylinders 4, wherein the lifting cylinders 4 can be existing hydraulic cylinders, the number of the lifting cylinders 4 is multiple and the lifting cylinders encircle the high pier concrete 2, and meanwhile, the lifting cylinders 4 synchronously lift by adopting an existing synchronous system. According to the construction requirement and safety of the flower stand 1 at present, the lifting oil cylinder 4 can be a 20-ton jack/oil cylinder with the specification of 5 meters at present.

Based on the above embodiment, another embodiment of the present utility model is that the lifting device includes a bearing frame and a jack, the jack is mounted on the bearing frame, the bearing frame is used for connecting an embedded part on the high pier concrete 2, the upper end of the jack is connected with the flower stand 1 and the support frame 3, and the flower stand 1 and the derrick 9 are driven by the jack to move upwards.

The bearing frame is of a steel frame structure, the bearing frame is arranged on an embedded part of the high pier concrete 2, the jack of the bearing frame can be fixed on the bearing frame, accordingly, load of the bearing frame is transferred to the high pier concrete through the bearing frame, the upper end of the jack can be transferred to the supporting frame, after the supporting frame 3 climbs under the action of the jack, the supporting frame 3 needs to be fixed, and then the bearing frame is detached. Due to the action of the rubber wheels 13, the climbing mode does not need to be provided with more complex structural units, and higher construction efficiency is obtained under a reasonable climbing height.

Based on the above embodiment, another embodiment of the present utility model is that the wheel set frame 11 is located above the support frame 3 and below the lifting device, and the distance between the wheel set frame 11 and the lifting device is greater than the upward travel of the support frame 3. The design of the position of the wheel set frame 11 is mainly used for avoiding the influence on the locking structure in the moving process of the lifting device, and the locking structure possibly needs to encircle the high pier concrete 2, so that the rubber wheel 13 is not mutually influenced with the lifting device in the working process through the dislocation arrangement of the wheel set frame 11 and the lifting device.

Referring to fig. 3 and 4, for better demolding and mold closing, a sliding groove is formed in the rear end of the pouring template A, a ball head is arranged in the sliding groove and used for sliding in the sliding groove, the movable end of the push-out mechanism B is connected with the ball head, a crane hoist is arranged above the pouring template A, and the crane hoist drives the pouring template A to move up and down. The pushing mechanism B is a jack, and the number of the jacks corresponds to the number of the ball heads in the sliding groove. The chain of the crane hoist is connected with the pouring template A, so that the pouring template A can be adjusted up and down. The number of installations is two per side. The hoisting block can be the existing chain block and electric block, so that the whole structure is simpler, and the installation is more convenient; before pouring, in order to prevent slurry leakage, when pouring the pouring template A, the pouring template A can be downwards wrapped for a certain distance each time, and double faced adhesive tape is adhered between the top edge of the poured structure and the pouring template A. Secondly, in order to prevent concrete from overflowing from the upper end of the pouring template A, the pouring template A is required to be arranged in an upper suspension mode, and therefore the actual design height of the pouring template A is larger than the pouring height. And pouring can be performed after the pouring template A is spliced and verified, so that the appearance quality of pouring control and piers is ensured. When the mould is disassembled, the pouring template A is driven to be far away from the concrete surface by the pushing mechanism, and after the distance between the pouring template A and the concrete surface is pulled, the pouring template A is cleaned and maintained. In order to fix the pouring template A before pouring, the ball head is provided with a positioning hole, and the side wall of the chute is provided with a pin hole corresponding to the positioning hole; the pin holes and the positioning holes are inserted with pins, and the pins are used for limiting the pouring template on the ball head. The number of the dowel holes on the side wall of the chute is multiple, gaps between two adjacent dowel holes can be the same, the dowel holes of the ball head correspond to the dowel holes of the chute in the chute by moving the pouring template up and down, and the ball head is locked in the chute by inserting the dowel holes and the dowel holes, so that the fixing of the pouring template on the pushing mechanism B is ensured.

The utility model can also be arranged in such a way that a transfer platform 7 is arranged at the top of the flower stand 1, wherein the transfer platform 7 is a frame platform at the top of the flower stand 1, a walking track 701 is arranged on the frame platform, the track 701 can be an existing crane track, the transfer platform 7 is provided with the walking track 701, the walking track 701 is provided with a winch 702, and the winch 702 is used for moving on the walking track 701. The traveling rail 701 is mainly used for restraining the winch 702, so that the winch 702 can hoist casting cement, a steel bar structure and other construction objects.

Reference throughout this specification to "one embodiment," "another embodiment," "an embodiment," "a preferred embodiment," etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment described in general terms in the present application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is intended that such feature, structure, or characteristic be implemented within the scope of the utility model.

Although the utility model has been described herein with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the scope and spirit of the principles of this disclosure. More specifically, various variations and modifications may be made to the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, drawings and claims of this application. In addition to variations and modifications in the component parts and/or arrangements, other uses will be apparent to those skilled in the art.

Claims

1. The utility model provides a high mound stable structure based on pergola climbs, includes pergola (1) around high mound concrete (2), high mound concrete (2) upper end is equipped with pier stud (13), be equipped with construction platform (8) on pergola (1), construction platform (8) are used for installing and pour the template; the method is characterized in that: the flower stand (1) is provided with a well-shaped frame (9), the well-shaped frame (9) is connected with the pier column (13) through a fastener, and the flower stand (1) transmits load to the pier column (13) through the well-shaped frame (9); lifting equipment is arranged on the high pier concrete (2), a support frame (3) is arranged on the flower stand (1), and the lifting equipment is used for applying thrust to the support frame (3) to enable the flower stand (1) and the cross frame (9) to move upwards; the side wall of the flower stand (1) is provided with a wheel set frame (11), the front end of the wheel set frame (11) is provided with a rubber wheel (12), and the rubber wheel (12) is used for abutting against the outer wall of the high pier concrete (2).

2. The high pier stabilization structure based on pergola climbing of claim 1, wherein: the wheel set frames (11) are a plurality of, the wheel set frames (11) are distributed around the high pier concrete (2), and the rubber wheels (12) are used for moving on the side wall of the high pier concrete (2) and restraining the flower frame (1).

3. The high pier stabilization structure based on pergola climbing of claim 1, wherein: lifting equipment includes first carrier (5), be equipped with lift cylinder (4) on first carrier (5), first carrier (5) lower extreme is equipped with first lock (501) that embraces, first lock (501) are fixed on high mound concrete (2), support frame (3) are connected to lift cylinder (4) upper end, support frame (3) lower extreme is equipped with third lock (301) that embraces.

4. A high pier stabilization structure based on pergola climbing as in claim 3, wherein: the lifting device comprises a second carrier (6), a second lock (601) is arranged at the lower end of the second carrier (6), the first carrier (5) and the second carrier (6) are both connected with a lifting oil cylinder (4), and the lifting oil cylinder (4) is locked on the high pier concrete (2) through a first lock (501) and a second lock.

5. The high pier stabilization structure based on pergola climbing of claim 4, wherein: the lifting cylinders (4) are multiple, and the lifting cylinders (4) are arranged on the first carrier (5) and the second carrier (6).

6. The high pier stabilization structure based on pergola climbing of claim 1, wherein: the lifting equipment comprises a bearing frame and a jack, wherein the jack is arranged on the bearing frame, the bearing frame is used for connecting an embedded part on a high pier concrete (2), the upper end of the jack is connected with a flower stand (1) and a supporting frame (3), and the flower stand (1) and a well-shaped frame (9) are driven by the jack to move upwards.

7. The high pier stabilization structure based on pergola climbing as claimed in claim 3 or 6, wherein: the wheel set frame (11) is positioned above the supporting frame (3) and below the lifting equipment, and the distance between the wheel set frame (11) and the lifting equipment is larger than the upward movement stroke of the supporting frame (3).