A camber measuring device for secondary tensioning of beam-slab
Patent Information
- Application Number
- CN202521460013.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-14
- Publication Date
- 2026-09-04
- Estimated Expiration
- 2035-07-14
AI Technical Summary
[0003]梁板二次张拉起拱度异常会导致预应力重新分配，可能破坏梁体原设计受力状态，引发侧弯或裂缝，严重时甚至导致工程事故；对梁板二次张拉的过程中，需要对梁板的起拱度进行监测，现有技术中通常利用水准仪测量起拱度，每次测量时均需调整水准仪找到基准线，然后进行测量起拱度，操作过程中费事费力，测量效率低
[0014] This utility model provides a camber measuring device for secondary tensioning of beams and slabs. When placing the precast beam, the center of the precast beam and the center of the observation platform are located in the same plane. Observation points are selected on the surface of the precast beam, with three observation points respectively located in the same plane as the center of the support base and the center of the marking plate on the surface of the observation platform. The leveling mechanism is used to make the measuring rod vertical. The laser emitter and the AC motor are turned on. The AC motor drives the screw to rotate. Utilizing the principle of screw transmission, the rotation of the screw drives the sliding sleeve to move upward along the screw, and the sliding sleeve drives the laser emitter to move, changing the laser height. When the laser shines on the indicator point on the side wall of the support base and the observation platform, the AC motor is turned off. The corresponding mark on the observation rod is recorded by the indicator arrow. The elevation observation points of the support base and the observation platform are denoted as X1, X2, and X3, respectively. After the precast beam is tensioned a second time, when it is necessary to calculate the camber, the measuring rod is first made vertical. The worker picks up a marker and places it on the observation point on the surface of the precast beam. The marker point is at the same height as the observation point. Similarly, the AC motor is turned on to push the sliding sleeve and the laser emitter upward. When the laser emitted by the laser emitter shines on the marker point, the scale corresponding to the laser emitter is recorded, and the lengths a, b, and c of the beam ends, middle and elevation observation points are calculated. The camber of the beam after the second tension can be directly calculated using the formula h=(X3+c)-[(X1+a)+(X2+b)]/2, which makes it easy for workers to quickly calculate the camber of the precast beam without the need for other tools, and the operation is simple and convenient.
Smart Images
Figure CN224719369U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of beam and slab tensioning technology, and in particular to a camber measuring device for secondary tensioning of beams and slabs. Background Technology
[0002] Secondary tensioning of beams and slabs refers to the second tensioning and locking of prestressed tendons after the prestressed concrete beam has been poured and cured. Secondary tensioning can improve the anchorage force, enhance the crack resistance of the beams and slabs, and accelerate the construction progress.
[0003] Abnormal camber during secondary tensioning of beams and slabs can lead to redistribution of prestress, potentially disrupting the original design stress state of the beam and causing lateral bending or cracks, or even causing engineering accidents in severe cases. During the secondary tensioning process of beams and slabs, it is necessary to monitor the camber. In existing technologies, a level is usually used to measure the camber. Each time a measurement is taken, the level must be adjusted to find the baseline before the camber is measured. This process is time-consuming, labor-intensive, and has low measurement efficiency.
[0004] Therefore, it is necessary to provide a new camber measurement device for secondary tensioning of beams and slabs to solve the above problems. Utility Model Content
[0005] The technical problem solved by this utility model is to provide a beam camber measuring device that is quick to measure and easy to operate for secondary tensioning of beams and slabs.
[0006] To solve the above-mentioned technical problems, the camber measuring device for secondary tensioning of beams and slabs provided by this utility model includes: a leveling mechanism, which is installed on the side wall of an observation platform. Support seats are symmetrically arranged on both sides of the observation platform, and a precast beam is placed on the surface of each support seat. Marking plates are provided on the precast beam, the support seats, and the side wall of the observation platform. Multiple measuring mechanisms are installed on the side wall of the leveling mechanism. Each measuring mechanism includes a measuring rod. Three measuring rods are installed on the side wall of the leveling mechanism. The side wall of each measuring rod has a sliding groove, and a sliding sleeve is slidably connected inside the groove. A laser emitter is fixedly connected to the side wall of the sliding sleeve. A screw is rotatably connected inside the measuring rod, and the screw is threadedly connected to the sliding sleeve. Multiple AC motors are installed inside the leveling mechanism, and the output shafts of the AC motors are connected to the screws.
[0007] Preferably, a rubber pad is installed on the surface of the support base, and the precast beam is placed on the surface of the rubber pad.
[0008] Preferably, the leveling mechanism includes a fixed housing, which is threadedly connected to a fixed shaft, and the sidewall of the fixed housing is threadedly connected to a fixed rod, wherein the fixed rod abuts against and presses against the surface of the fixed shaft.
[0009] Preferably, a metal ball is fixedly connected to the bottom end of the fixed shell, and the center of the metal ball and the center of the fixed shaft are located in the same plane.
[0010] Preferably, a glass tube for storing water droplets is mounted on the surface of the fixed shell, and scale lines are provided on the side wall of the glass tube and the side wall of the measuring rod; on the scale lines on the side wall of the measuring rod, the scale lines on the surface of the scale lines are aligned with the center of the fixed shaft.
[0011] Preferably, the side wall of the sliding sleeve is provided with an indicator arrow, and the indicator arrow points to the scale line on the side wall of the measuring rod.
[0012] Preferably, a marking point is provided at the center of the marking plate, and a laser emitted from inside the laser emitter illuminates the marking point.
[0013] Compared with related technologies, the camber measuring device for secondary tensioning of beams and slabs provided by this utility model has the following beneficial effects:
[0014] This utility model provides a camber measuring device for secondary tensioning of beams and slabs. When placing the precast beam, the center of the precast beam and the center of the observation platform are located in the same plane. Observation points are selected on the surface of the precast beam, with three observation points respectively located in the same plane as the center of the support base and the center of the marking plate on the surface of the observation platform. The leveling mechanism is used to make the measuring rod vertical. The laser emitter and the AC motor are turned on. The AC motor drives the screw to rotate. Utilizing the principle of screw transmission, the rotation of the screw drives the sliding sleeve to move upward along the screw, and the sliding sleeve drives the laser emitter to move, changing the laser height. When the laser shines on the indicator point on the side wall of the support base and the observation platform, the AC motor is turned off. The corresponding mark on the observation rod is recorded by the indicator arrow. The elevation observation points of the support base and the observation platform are denoted as X1, X2, and X3, respectively. After the precast beam is tensioned a second time, when it is necessary to calculate the camber, the measuring rod is first made vertical. The worker picks up a marker and places it on the observation point on the surface of the precast beam. The marker point is at the same height as the observation point. Similarly, the AC motor is turned on to push the sliding sleeve and the laser emitter upward. When the laser emitted by the laser emitter shines on the marker point, the scale corresponding to the laser emitter is recorded, and the lengths a, b, and c of the beam ends, middle and elevation observation points are calculated. The camber of the beam after the second tension can be directly calculated using the formula h=(X3+c)-[(X1+a)+(X2+b)] / 2, which makes it easy for workers to quickly calculate the camber of the precast beam without the need for other tools, and the operation is simple and convenient. Attached Figure Description
[0015] Figure 1 A schematic diagram of a preferred embodiment of the camber measuring device for secondary tensioning of beams and slabs provided by this utility model;
[0016] Figure 2 for Figure 1 The diagram shows an enlarged view of the structure at point A.
[0017] Figure 3 for Figure 2 The image shows a front view of the internal structure of the fixed shell.
[0018] Figure 4 for Figure 2 The image shows a side view of the internal structure of the fixed shell.
[0019] Figure 5 for Figure 2 Top view of the internal structure of the measuring rod shown;
[0020] Figure 6 for Figure 1 The side view of the precast beam structure shown.
[0021] The following are the labels in the diagram: 1. Precast beam, 2. Support base, 21. Rubber pad, 3. Observation platform, 4. Leveling mechanism, 41. Fixed shell, 42. Metal ball, 43. Glass tube, 44. Fixed rod, 45. Fixed shaft, 5. Measuring mechanism, 51. Measuring rod, 52. Scale line, 53. Sliding sleeve, 54. Laser emitter, 55. Indicating arrow, 56. AC motor, 57. Screw, 58. Slide groove, 6. Marker plate, 61. Marker point. Detailed Implementation
[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0023] Please see Figures 1 to 6 , Figure 1 A schematic diagram of a preferred embodiment of the camber measuring device for secondary tensioning of beams and slabs provided by this utility model; Figure 2 for Figure 1 The diagram shows an enlarged view of the structure at point A. Figure 3 for Figure 2 The image shows a front view of the internal structure of the fixed shell. Figure 4 for Figure 2 The image shows a side view of the internal structure of the fixed shell. Figure 5 for Figure 2 Top view of the internal structure of the measuring rod shown; Figure 6 for Figure 1The image shows a side view of a precast beam structure. A camber measuring device for secondary tensioning of a beam slab includes a leveling mechanism 4, which is installed on the side wall of an observation platform 3. Support seats 2 are symmetrically arranged on both sides of the observation platform 3. The leveling mechanism 4 includes a fixed shell 41, which is threadedly connected to a fixed shaft 45. The side wall of the fixed shell 41 is threadedly connected to a fixed rod 44, and the fixed rod 44 abuts against and presses against the surface of the fixed shaft 45. A metal ball 42 is fixedly connected to the bottom end of the fixed shell 41. The center of the metal ball 42 is in the same plane as the center of the fixed shaft 45. The weight of the metal ball 42 is much greater than the weight of the fixed shell 41 and its internal devices. Under the action of gravity, the metal ball 42 pushes the fixed shell 41 to rotate, so that the fixed shell 41, the metal ball 42 and the measuring rod 51 are in a vertical state. When it is necessary to fix the fixed shell 41, the fixing rod 41 is rotated, so that the fixing rod 41 presses against the side wall of the fixed shaft 45 to prevent the fixed shell 41 from rotating. At the same time, the horizontal standard line for measuring and controlling the camber of the bridge passes through the center of the fixed shaft 45. The fixed shell 41 and the measuring rod 51 are both perpendicular to the standard line.
[0024] A precast beam 1 is placed on the surface of the support base 2. Marker plates 6 are set on the side walls of the precast beam 1, the support base 2, and the observation platform 3. A marker point 61 is set at the center of the marker plate 6, and the laser emitted from inside the laser emitter 54 illuminates the marker point 61. In order to facilitate the laser aiming at the marker point 61, the scale corresponding to the laser emitter 54 on the measuring rod 51 can be read at this time.
[0025] Multiple measuring mechanisms 5 are installed on the side wall of the leveling mechanism 4. Each measuring mechanism 5 includes a measuring rod 51. Three measuring rods 51 are installed on the side wall of the leveling mechanism 4. The side wall of each measuring rod 51 is provided with a sliding groove 58. A sliding sleeve 53 is slidably connected inside the sliding groove 58, and a laser emitter 54 is fixedly connected to the side wall of the sliding sleeve 53. A screw 57 is rotatably connected inside the measuring rod 51, and the screw 57 is threadedly connected to the sliding sleeve 53. Multiple AC motors 56 are installed inside the leveling mechanism 4, and the output shaft of each AC motor 56 is connected to the screw 57. In order to facilitate the adjustment of the direction of the screw 57 by controlling the forward and reverse rotation of the AC motors 56, the principle of screw transmission is used. The rotation of the screw 57 drives the sliding sleeve 53 to move up and down along the screw 57 in a straight line, and the sliding sleeve 53 drives the laser emitter 54 to move, changing the height of the laser so that the laser can irradiate the marked point 61.
[0026] A rubber pad 21 is installed on the surface of the support base 2, and the precast beam 1 is placed on the surface of the rubber pad 21. In order to facilitate the rubber pad 21 to provide support for the precast beam 1 and avoid damage at the contact point between the beam and the rubber pad 21 during secondary tensioning.
[0027] A glass tube 43 for storing water droplets is installed at the center of the surface of the fixed shell 41. The side wall of the glass tube 43 and the side wall of the measuring rod 51 are both provided with scale lines 52. In order to facilitate viewing the position of the water droplets inside the glass tube 43, when the water droplets inside the glass tube 43 are in the middle position, it can be known that the fixed shell 41 is in a vertical state.
[0028] On the scale line 52 on the side wall of the measuring rod 51, the 0 mark on the surface of the scale line 52 is aligned with the center of the fixed shaft 45; the side wall of the sliding sleeve 53 is provided with an indicator arrow 55, and the center position of the laser sensor 54 is aligned with the center position of the indicator arrow 55; and the indicator arrow 55 points to the scale line 52 on the side wall of the measuring rod 51, so as to facilitate understanding the scale corresponding to the center point of the laser sensor 54 by means of the scale indicated by the indicator arrow 55.
[0029] The working principle of the beam camber measuring device for secondary tensioning of beams and slabs provided by this utility model is as follows: When the precast beam 1 is tensioned for the second time, the precast beam 1 is placed on the surface of the rubber pad 21. The center of the precast beam 1 and the center of the observation platform 3 are located in the same plane. Observation points are selected on the surface of the precast beam 1. The observation points should be set at the bottom end of the precast beam 1. The three observation points 6 are respectively located in the same plane as the center of the marking plate 6 on the surface of the support 2 and the observation platform 3. At this time, the observation points are marked with ink on the side wall of the precast beam 1. The three observation points correspond to the support 2 and the observation platform 3, respectively. Rotating the fixing rod 44 separates it from the fixing shaft 45. The weight of the metal ball 42 is much greater than the weight of the fixing shell 41 and its internal components. Under the influence of gravity, the metal ball 42 pushes the fixing shell 41 to rotate, bringing the fixing shell 41, the metal ball 42, and the measuring rod 51 into a vertical position. Observe the position of the water droplets inside the glass tube 43. When the water droplets inside the glass tube 43 are in the middle position, it can be determined that the fixing shell 41 is in a vertical position. When it is necessary to fix the fixing shell 41, rotate the fixing rod 41 to press against the side wall of the fixing shaft 45, preventing the fixing shell 41 from rotating. At the same time, the horizontal standard line for measuring and controlling the camber of the bridge passes through the center of the fixing shaft 45. Connect the device to an external power source and turn on the laser emitter 54 and the AC motor 56. The AC motor 56 drives the screw 57 to rotate. Utilizing the principle of screw transmission, the rotation of the screw 57 causes the sliding sleeve 53 to move upwards along the screw 57, and the sliding sleeve 53 drives the laser emitter 54 to move, changing the laser height. When the laser illuminates the indicator point 61 on the side wall of the support base 2 and the observation platform 3, turn off the AC motor 56. Record the corresponding scale on the observation rod 51 using the indicator arrow 55, which represents the elevation of the support base 2 and the observation platform 3, respectively. The observation points are denoted as X1, X2, and X3. After the precast beam 1 undergoes secondary tensioning, when calculating the camber, the measuring rod 51 is first made vertical. A worker picks up a marker 6 and places it on the observation point on the surface of the precast beam 1. The marker 61 is at the same height as the observation point. Similarly, the AC motor 56 is turned on, pushing the sliding sleeve 53 and the laser emitter 54 upward. When the laser emitted by the laser emitter 54 illuminates the marker 61, the scale corresponding to the laser emitter 54 is recorded, and the lengths a, b, and c of the beam's two ends, middle, and elevation observation points are calculated (as shown in the attached figure). Figure 1 (As shown); the camber after the secondary tensioning of the beam slab can be directly calculated using the formula h=(X3+c)-[(X1+a)+(X2+b)] / 2, which facilitates workers in monitoring the camber of the precast beam 1.
[0030] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.
Claims
1. A device for measuring camber during secondary tensioning of beams and slabs, characterized in that, include: A leveling mechanism (4) is installed on the side wall of the observation platform (3). Support seats (2) are symmetrically arranged on both sides of the observation platform (3). A precast beam (1) is placed on the surface of the support seat (2). Marking plates (6) are set on the side walls of the precast beam (1), the support seat (2) and the observation platform (3). The leveling mechanism (4) has multiple measuring mechanisms (5) installed on its side wall. Each measuring mechanism (5) includes a measuring rod (51). Three measuring rods (51) are installed on the side wall of the leveling mechanism (4). The side wall of the measuring rod (51) is provided with a sliding groove (58). The sliding groove (58) is slidably connected to a sliding sleeve (53), and the side wall of the sliding sleeve (53) is fixedly connected to a laser emitter (54). The measuring rod (51) is rotatably connected to a screw (57), and the screw (57) is threadedly connected to the sliding sleeve (53). The leveling mechanism (4) has multiple AC motors (56) installed inside, and the output shaft of the AC motors (56) is connected to the screw (57).
2. The camber measuring device for secondary tensioning of beams and slabs according to claim 1, characterized in that, A rubber pad (21) is installed on the surface of the support base (2), and the precast beam (1) is placed on the surface of the rubber pad (21).
3. The camber measuring device for secondary tensioning of beams and slabs according to claim 1, characterized in that, The leveling mechanism (4) includes a fixed shell (41), which is threadedly connected to a fixed shaft (45). The side wall of the fixed shell (41) is threadedly connected to a fixed rod (44), and the fixed rod (44) abuts against and presses the surface of the fixed shaft (45).
4. The camber measuring device for secondary tensioning of beams and slabs according to claim 3, characterized in that, The bottom end of the fixed shell (41) is fixedly connected to a metal ball (42), and the center of the metal ball (42) and the center of the fixed shaft (45) are located in the same plane.
5. The camber measuring device for secondary tensioning of beams and slabs according to claim 3, characterized in that, A glass tube (43) for storing water droplets is installed on the surface of the fixed shell (41). The side wall of the glass tube (43) and the side wall of the measuring rod (51) are provided with scale lines (52). On the scale line (52) on the side wall of the measuring rod (51), the 0 scale line on the surface of the scale line (52) is aligned with the center of the fixed shaft (45).
6. The camber measuring device for secondary tensioning of beams and slabs according to claim 5, characterized in that, The side wall of the sliding sleeve (53) is provided with an indicator arrow (55), and the indicator arrow (55) points to the scale line (52) on the side wall of the measuring rod (51).
7. The camber measuring device for secondary tensioning of beams and slabs according to claim 1, characterized in that, The marker (6) has a marker point (61) at its center, and a laser emitted from inside the laser emitter (54) illuminates the marker point (61).