Deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams

Abstract

This invention provides a method for detecting the deformation of a beam support for a large-span, high-web channel beam of irregular shape. The beam support forms a web area with deformation to be detected. The method includes the following steps: placing precast blocks on the top surface of the beam support and on both sides of the web area; stacking first pre-compression sandbags on the top surface of the beam support and between the precast blocks; placing a Bailey beam corresponding to the beam support on top of the precast blocks; setting several prism-free reflectors at the bottom of the longitudinal beams; applying pressure to the Bailey beams; and collecting the light wave data of the prism-free reflectors with a total station to measure the change data of the web area of ​​the beam support, thereby obtaining the deformation data of the beam support. This invention improves the detection accuracy of the beam support by setting Bailey beams on top of the precast blocks and pre-compression sandbags, applying pressure to the Bailey beams, and detecting the deformation data of the longitudinal beams in real time.

Description

Technical Field

[0001] This invention relates to the field of beam construction technology, and in particular to a method for detecting the deformation of beam supports for irregularly shaped, large-span, high-web trough beams. Background Technology

[0002] Currently, preloading of cast-in-place beams often employs a method of overloading the bottom slab and reducing the load on the web. The preloading height of the web is approximately 2:1 compared to the top and bottom slabs. This load-bearing test cannot accurately reflect the deformation data of the beam support during the construction process of forming the channel beam, and therefore cannot guide construction. Furthermore, the local concentrated load height on the web is large, making it difficult to reinforce the preloading material in the web, resulting in high safety risks. The large overload of the bottom slab preloading also poses a risk of instability and damage to the intermediate longitudinal beams. Summary of the Invention

[0003] In view of the above, the present invention provides a deformation detection method for beam supports of irregular large-span high-web trough beams, which solves the technical problem that traditional beam support pre-compression tests are difficult to accurately reflect the actual stress. By setting Bailey beams on the top of precast blocks and pre-compression sandbags, applying pressure to the Bailey beams, and detecting the deformation data of the longitudinal beams in real time, the real-time stress of the beam support can be detected, thereby improving the detection accuracy of the beam support.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A method for detecting the deformation of a beam support for an irregularly shaped, large-span, high-web channel beam, wherein the beam support forms a web region with deformation to be detected, and the deformation detection method includes the following steps:

[0006] Provide the precast block and place it on the top surface of the beam support and on both sides of the web area;

[0007] A number of first pre-compression sandbags are provided and stacked on the top surface of the beam support and located between the precast blocks;

[0008] Provide a Bailey beam, and place the Bailey beam on top of the precast block, corresponding to the beam support;

[0009] Several prism-free reflectors and a total station are provided. The prism-free reflectors are placed at the bottom of the beam support. By applying pressure to the Bailey beam, the total station collects the light wave data of the prism-free reflectors to measure the change data of the web area of ​​the beam support, thereby obtaining the deformation data of the beam support.

[0010] A further improvement to the deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams of the present invention is that it further includes:

[0011] Several base plates are provided and laid on top of the web area. The precast block and the first pre-compression sandbag are placed on the top surface of the base plates.

[0012] A further improvement to the deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams of the present invention is that it further includes:

[0013] A pad is provided and placed on top of the Bailey beam, thereby applying pressure to the pad.

[0014] A further improvement to the deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams of the present invention is that it further includes:

[0015] A number of support rods are provided and fixed at intervals to the top of the Bailey beam, and the pad is placed on top of the support rods.

[0016] A further improvement to the deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams of the present invention is that it further includes:

[0017] Provide several second pre-compression sandbags and place them on top of the pad.

[0018] A further improvement to the deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams of the present invention is that it further includes:

[0019] Several second preloaded sandbags, with a total design load equal to that of the web area of ​​the beam support, are stacked on top of the pad.

[0020] A further improvement to the deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams of the present invention is that it further includes:

[0021] Several second preloaded sandbags, with a local design load capacity equal to that of each point in the web region of the beam support, are stacked on top of the pad plate at the corresponding points.

[0022] A further improvement to the deformation detection method for the beam support of the irregularly shaped, large-span, high-web trough beam of the present invention is that, when the second pre-compression sandbag is piled up to 60% of the total design load-bearing weight of the web area of ​​the beam support, the method further includes:

[0023] After 36 hours of observation and the acquisition of light wave data of the prism-free reflector using a total station, the remaining second pre-compression sandbags were piled onto the pad after the light wave data remained unchanged within the set time range.

[0024] A further improvement to the deformation detection method for the beam support of the irregularly shaped, large-span, high-web trough beam of the present invention is that, when the second pre-compression sandbag is piled up to the design total load-bearing weight of the web area of ​​the beam support, it further includes:

[0025] The observation lasted 72 hours, and the total station was used to collect the light wave data of the prism-free reflector.

[0026] A further improvement to the deformation detection method for the beam support of the irregularly shaped, large-span, high-web trough beam of the present invention is that, before stacking the second pre-compression sandbag, the method further includes:

[0027] After 36 hours of observation and the acquisition of light wave data of the prism-free reflector using the total station, the second pre-compression sandbag is stacked after the light wave data remains unchanged within the set time range.

[0028] The present invention provides a deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams. By setting precast blocks and pre-compression sandbags on the top surface of the beam support, the deformation data of the web area of ​​the beam support can be easily measured, improving the accuracy of applied pressure. Furthermore, Bailey beams are set on top of the precast blocks and pre-compression sandbags. By applying pressure to the Bailey beams and detecting their deformation data in real time, the real-time stress condition of the beam support can be detected. The stacking of a second pre-compression sandbag allows for pre-loading according to the load changes during the actual casting of the beam support, improving the detection accuracy of the beam support. It also enables deformation detection data by part and region, further improving the accuracy of web area deformation detection. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a side sectional view of the deformation detection method for the beam support of the irregular large-span high-web trough beam of the present invention.

[0031] Figure 2 This is a front sectional view of the deformation detection method for the beam support of the irregular large-span high-web trough beam of the present invention.

[0032] The correspondence between the reference numerals and components in the attached drawings is as follows: base plate 1, precast block 2, first pre-compression sandbag 3, Bailey beam 4, support rod 5, pad plate 6, second pre-compression sandbag 7, longitudinal beam 8. Detailed Implementation

[0033] To facilitate understanding of the present invention, the following description is provided in conjunction with the accompanying drawings and embodiments.

[0034] Please see Figures 1 to 2 This invention provides a deformation detection method for a beam support of an irregularly shaped, large-span, high-web channel beam. The beam support forms a web area with deformation to be detected. The deformation detection method includes the following steps:

[0035] Provide the precast block 2, and place the precast block 2 on the top surface of the beam support and on both sides of the web area;

[0036] A number of first pre-compression sandbags 3 are provided, and the first pre-compression sandbags 3 are stacked on the top surface of the beam support and located between the precast blocks 2;

[0037] Provide a Bailey beam 4, and place the Bailey beam 4 on top of the precast block 2 in relation to the beam support;

[0038] A number of prism-free reflectors and a total station are provided. The prism-free reflectors are placed at the bottom of the beam support. By applying pressure to the Bailey beam 4, the total station collects the light wave data of the prism-free reflectors to measure the change data of the web area of ​​the beam support, thereby obtaining the deformation data of the beam support.

[0039] Preferably, the beam support includes several base stones fixed to the ground, steel columns erected on the base stones, steel crossbeams fixed to the top of the steel columns, and longitudinal beams 8 fixed to the top of the steel crossbeams. A web area is formed in the middle of the longitudinal beam 8. Several prism-free reflectors and a total station are installed at the bottom of the longitudinal beam 8. Precast blocks 2 and first pre-stressed sandbags 3 are placed on the top surface of the longitudinal beam 8. A preferred embodiment of the deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam of the present invention further includes:

[0040] A number of base plates 1 are provided, which are laid on top of the longitudinal beam, and the precast block 2 and the first pre-compression sandbag 3 are placed on the top surface of the base plate 1.

[0041] Furthermore, it also includes:

[0042] A pad 6 is provided and placed on top of the Bailey beam 4, thereby applying pressure to the pad 6.

[0043] Furthermore, it also includes:

[0044] A number of support rods 5 are provided and fixed at intervals to the top of the Bailey beam 4, and a pad 6 is placed on the top of the support rods 5.

[0045] Preferably, a number of support rods 5 are spaced apart along the width direction of the Bailey beam 4.

[0046] Furthermore, it also includes:

[0047] A plurality of second pre-compression sandbags 7 are provided and placed on top of the pad 6 to apply pressure to the pad 6.

[0048] Furthermore, it also includes:

[0049] Several second preloaded sandbags 7, with a total design load-bearing weight equal to that of the web area of ​​the beam support, are stacked on top of the pad plate 6.

[0050] Specifically, it also includes:

[0051] Several second preloaded sandbags 7, with the same local design load capacity as each point in the web area of ​​the beam support, are stacked on top of the pad plate 6 to simulate the construction scenario when the beam support is poured with concrete, the beam surface is constructed, and the structure on the beam, thereby improving the accuracy of the load-bearing test of the beam support.

[0052] Preferably, it also includes:

[0053] There are four precast blocks 2, and the four precast blocks 2 are identical in shape and equal in weight.

[0054] Furthermore, when the second pre-compression sandbag 7 is stacked to the web area of ​​the beam support to bear the total design weight, it also includes:

[0055] The observation lasted 72 hours, and the total station was used to collect the light wave data of the prism-free reflector.

[0056] Specifically, when the second pre-compression sandbag 7 is stacked to 60% of the total design load-bearing weight of the web area of ​​the beam support, it also includes:

[0057] After 36 hours of observation and the acquisition of light wave data of the prism-free reflector using a total station, the remaining second pre-compression sandbags were piled onto the pad after the light wave data remained unchanged within the set time range.

[0058] Preferably, a second preloading sandbag 7 is evenly distributed from the middle to both ends of the pad 6. When the preloading reaches 60% of the preloading weight of the web, the light wave data of the prism-free reflector is collected using a total station to collect the preloading data. The data is continuously observed for 36 hours. Preloading is carried out after the settlement difference meets the requirements. This avoids the total weight being completely pressed onto the beam support and the beam support bearing capacity not meeting the standard, which would directly cause the beam support to collapse. This makes it easier to remedy the beam support.

[0059] Furthermore, before stacking the second pre-compression sandbag, the following steps are also included:

[0060] After 36 hours of observation and the acquisition of light wave data of the prism-free reflector using the total station, the second pre-compression sandbag is stacked after the light wave data remains unchanged within the set time range.

[0061] Preferably, the Bailey beam includes several unit frames arranged along the width direction of the beam support.

[0062] Preferably, before preloading the beam support, the bottom web of the beam is laid out, and the appropriate length is selected according to the web changes to divide it into blocks and number them. The load distribution of the web at each stage is calculated and the required amount of preloading material is determined. Prismless reflectors are pasted on the bottom of the longitudinal beam, and initial data is collected using a total station.

[0063] Preferably, the precast blocks of the beam support are laid out from the middle to both ends by two cranes according to the pouring sequence. At the same time, the first pre-compression sandbag with a weight of 1.2 times that of the bottom plate is laid out at the same time as the pre-compression block to simulate the pouring process of the bottom plate and the web section with the same height as the bottom plate. After the pre-compression is laid out, the data after the pre-compression is completed is collected by a total station.

[0064] Preferably, the top of the precast blocks uses 90cm transverse Bailey bridges at 90cm transverse intervals as the main beam, with I-beams used as distribution beams along the bridge direction, and bamboo plywood laid as pads to reduce the height of the web preloading. Secondary preloading sandbags are evenly distributed on the pads from the middle to both ends. When the preloading reaches 60% of the web preloading weight, preloading data is collected and continuously monitored for 36 hours. Preloading continues after the settlement difference meets the requirements. Horizontal loading continues, and when the loading height reaches the preloading weight of the end concrete, the preloading height is gradually adjusted from the middle of the beam to both ends according to the web alignment, until the highest point in the middle of the web reaches 100% of the preloading weight. This stage simulates the load conditions of the web reinforcement and concrete pouring acting on the bottom surface of the web, and also simulates the most unfavorable stress state of the web concrete under different load positions.

[0065] Specifically, continuous observation is conducted for 72 hours, preloading data is collected, and once the settlement difference meets the requirements, unloading is carried out in stages in the reverse order of preloading, and data at each stage is recorded.

[0066] The present invention provides a deformation detection method for beam supports of irregularly shaped, large-span, high-web trough beams. By setting precast blocks and pre-compression sandbags on the top surface of the beam support, the curvature of the beam support surface is eliminated, improving the accuracy of pressure application. Bailey beams are then set on top of the precast blocks and pre-compression sandbags. Pressure is applied to the Bailey beams, and the deformation data of the Bailey beams is detected in real time to detect the real-time stress condition of the beam support. By stacking a second pre-compression sandbag, pre-compression can be carried out according to the load changes during the actual construction of the beam support, improving the detection accuracy of the beam support.

[0067] A specific implementation example of the deformation detection method for the beam support of the irregular large-span high-web trough beam of the present invention is as follows: Before stacking the second pre-compression sandbags, observe for 36 hours and collect the light wave data of the prism-free reflector using a total station. After the light wave data remains unchanged within a set time range, stack the second pre-compression sandbags. Distribute the second pre-compression sandbags 7 evenly from the middle to both ends on the pad 6. When the pre-compression reaches 60% of the pre-compression weight of the web, collect the light wave data of the prism-free reflector using a total station to collect pre-compression data. Observe continuously for 36 hours. After the settlement difference meets the requirements, pre-compression is carried out. Continue to horizontally stack the second pre-compression sandbags 7. When the stacking height reaches the pre-compression weight of the end concrete, adjust the pre-compression height of the stacked material gradually from the middle part of the beam to both ends according to the change of the web line shape, until the highest part in the middle of the web reaches 100% of the pre-compression weight. Observe continuously for 72 hours, collect pre-compression data, and after the settlement difference meets the requirements, unload in stages according to the reverse order of pre-compression, and record the data of each stage.

[0068] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for detecting the deformation of a beam support for an irregularly shaped, large-span, high-web channel beam, wherein the beam support forms a web region with the deformation to be detected, characterized in that, The deformation detection method includes the following steps: Provide precast blocks and place them on the top surface of the beam support and on both sides of the web area; A plurality of first pre-compression sandbags are provided, and the first pre-compression sandbags are stacked on the top surface of the beam support and located between the precast blocks; Provide Bailey beams and place the Bailey beams on top of the precast blocks, corresponding to the beam supports; A number of prism-free reflectors and a total station are provided. The prism-free reflectors are placed at the bottom of the beam support. By applying pressure to the Bailey beam, the total station collects the light wave data of the prism-free reflectors to measure the change data of the web area of ​​the beam support, thereby obtaining the deformation data of the beam support.

2. The deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams according to claim 1, characterized in that, Also includes: Several base plates are provided, and the base plates are laid on top of the web area. The precast blocks and the first pre-compression sandbags are placed on the top surface of the base plates.

3. The deformation detection method for beam supports of irregularly shaped, large-span, high-web channel beams according to claim 1, characterized in that, Also includes: A pad is provided and placed on top of the Bailey beam, thereby applying pressure to the pad.

4. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 3, characterized in that, Also includes: A plurality of support rods are provided and fixed at intervals to the top of the Bailey beam, and the pad is placed on top of the support rods.

5. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 4, characterized in that, Also includes: A number of second pre-compression sandbags are provided and placed on top of the pad.

6. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 5, characterized in that, Also includes: Several second preloaded sandbags, with a total design load-bearing weight equal to that of the web area of ​​the beam support, are stacked on top of the pad.

7. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 6, characterized in that, Also includes: Several second preloaded sandbags, with a local design load capacity equal to that of each point in the web region of the beam support, are stacked on top of the pad plate at the corresponding points.

8. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 7, characterized in that, When the second pre-compression sandbags are piled up to 60% of the total design load-bearing weight of the web area of ​​the beam support, the following steps are also included: After 36 hours of observation and the acquisition of light wave data of the prism-free reflector using a total station, the remaining second pre-compression sandbags are piled onto the pad after the light wave data remains unchanged within a set time range.

9. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 5, characterized in that, When the second preloaded sandbags are piled up to the web area of ​​the beam support designed to bear the total weight, the following is also included: The observation lasted for 72 hours, and the total station was used to collect the light wave data of the prism-free reflector.

10. The deformation detection method for the beam support of the irregularly shaped, large-span, high-web channel beam according to claim 1, characterized in that, Before applying pressure to the Bailey beam, the following is also included: The light wave data of the prism-free reflector was collected using the total station for 36 hours. After the light wave data remained unchanged within a set time range, pressure was applied to the Bailey beam.

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