CN101334261B - Monitoring device for monitoring scour depth of river bed, remote automatic monitoring system and bridge - Google Patents

Abstract

The invention relates to a monitoring device for monitoring the scouring depth of a riverbed, a remote automatic monitoring system and a bridge. A monitoring devices for monitoring bridge foundation riverbed scouring depth, it includes: at least one gravity detection rod, one end of which is connected with the riverbed in an abutting mode, and the other end of which extends towards the vertical direction; at least one protective sleeve, the center of which is used for the gravity detection rod to pass through and allowing the gravity detection rod to slide in the vertical direction; and at least one sliding sleeve, one end of which is provided with a guide part loosely sleeved outside the sleeve, and the other end of which is fixed on the bridge pier of the bridge and is used for maintaining the sleeve and the gravity detection rod to slide in the vertical direction. Therefore, when the river bed sinks due to scouring, the gravity detection rod and the protection sleeve also descend, scouring data is obtained in real time through level slip, and further warning and traffic control are carried out to prevent accidental injury. The invention also discloses a remote monitoring system and a bridge with an automatic monitoring function.

Description

Monitoring device for monitoring scour depth of river bed, remote automatic monitoring system and bridge

technical field

The invention relates to a bridge foundation monitoring device, especially a monitoring device and a remote monitoring system that can automatically monitor the scour depth and further give an alarm to prevent accidental damage when the vicinity of bridge foundation piles is severely scoured during typhoon storms.

Background technique

Steep and turbulent rivers with arbitrary slopes, or when there is a typhoon and sudden rainstorm and flood fluctuations, the piers and abutment foundations are often hollowed out due to the erosion of the river bed. However, due to the turbulent water flow and the easy movement of the river bed, its effect is often not good. For example, as shown in Figure 1a, it endangers the original exposed bridge foundation, and even causes the bridge to tilt and collapse, causing traffic interruption, and causing great harm to people's lives and property.

The total scour depth that a bridge section may suffer includes general scour (General Scour) and localized scour (Localized Sour). General scour refers to the overall decline of the river bed, which is mainly caused by natural or human factors, which makes the river sediment migration unbalanced; localized scour can be further divided into (1) contraction scour, which refers to the The scouring behavior of the riverbed caused by the reduction of the cross-section of the bridge and the increase of the flow velocity caused by the installation of bridges; (2) Local scour of bridge piers and bridge abutments (Local Scour) means that when the flood flows through the bridge piers or bridge abutments, the subbed around the bridge foundation is affected. The washing phenomenon around the piers or abutments caused by eddy current erosion.

For example, Figure 1b shows the localized scour phenomenon near the bridge foundation piles, which belongs to constriction scour. When the water flows through the bridge piers, the pier columns face the water surface and are scoured and hollowed out; The effect is obviously increased, and the local scour of piers and abutments will have huge energy to hollow out the bridge foundation, causing the driftwood or rocks on the piles to crash and even cause the bridge to collapse. The real-time warning and control of the car becomes very important.

Known technologies for monitoring the scouring depth of bridge foundation piles include ultrasonic measurement, traditional gravity measurement, and optical fiber measurement.

The disadvantage of ultrasonic measurement is that sound waves are highly sensitive to temperature, and it is difficult to define the ambient temperature due to the wide range involved. Furthermore, the sound wave transmission path passes through different media (such as turbid river water), which affects the measurement accuracy of the sound wave velocity value. In addition, sound waves are easily disturbed by surrounding noises during travel, especially during typhoon storms, eddy current disturbances, drifting wood and rock impacts, and strong winds. In short, ultrasonic measurement technology is gradually being eliminated due to poor applicability.

For example, the gravity scour measurement device of Taiwan Patent No. 172,991 discloses a noose to extend the weight along the fixed sleeve to the scour surface, and measure the scour depth by the retraction of the noose. But its disadvantage is that the weight is easily drifted by the interference of flood, eddy current or driftwood, which makes it difficult to measure in flood and the measured data is not easy to be accurate. Furthermore, the measured riverbed surface cannot be judged as a scoured surface or a river surface that has been silted up. Finally, the large boulder driftwood can easily damage the casing and even have problems with tangling the noose.

Another example is the optical fiber measurement technology of Taiwan Patent No. 199,325, which discloses a riverbed sediment scour monitoring device, which uses a flexible rod body with a built-in fiber grating sensing unit to stand upright on the riverbed. When the riverbed scours to a predetermined height , the scour depth can be monitored through the flexural strain generated by the optical fiber and the corresponding physical quantity changes obtained by the analyzer. The advantages of optical fiber measurement technology are noise-free and multi-point telemetry, but there are also many disadvantages, including the difficulty of installing the monitoring instrument under the water surface, and it is easily damaged by floating stones on the river bed, and it is difficult to maintain after installation, especially in typhoons. There is often a crisis of power outages (communications) in harsh environments such as heavy rains.

Another example is the invention patent of Taiwan, China, application No. 094102692 "Water guiding and anti-scouring device for bridge piers", which discloses a device that uses water guiding and drainage to guide water upward or sideways to prevent water from jetting down to hollow out the river bed. The inventor It is claimed that the current anti-scouring effect can reach 50% to 70%. However, the meaning of anti-scouring effect is different from real-time monitoring. Although the former can reduce the scour, it cannot know whether the scour depth has reached a dangerous stage.

Contents of the invention

The main purpose of the present invention is to provide a monitoring device, which can automatically monitor the scour depth of the riverbed of the bridge foundation, so as to improve the deficiency of the traditional riverbed scour monitoring system.

In order to achieve the above object and other objects, the monitoring device of the present invention mainly includes: a gravity detection rod, a high-strength stainless steel rod body with a solid heavy mass, and a plurality of scales for indicating the scour depth are formed on the surface, and the lower end contains a The disc-shaped abutting portion expanding in the radial direction abuts against the river bed, and the upper end extends vertically. The protective sleeve has an inner sleeve and an outer sleeve, which are connected as a whole by a plurality of reinforcing steel bars, and the inner diameter of the inner sleeve allows the gravity detection rod to pass through and allow it to slide in the vertical direction. The sliding sleeve has a guiding part at one end and is loosely set on the outside of the sleeve, and the other end is fixed on the pier of the bridge for maintaining the sleeve and the gravity detection rod to slide vertically. In this way, when the river bed sinks due to scouring, the gravity detection rod and the protective sleeve also descend accordingly, and the correct scouring depth can be obtained through the relative displacement with the standard on the bridge pier.

According to the present invention, the gravity detection rod measures the scour depth through gravity, the protective sleeve is used to strengthen the resistance against the impact of drifting objects, and the sliding sleeve is used to support and maintain the sliding direction of the two. Its structure is simple, anti-collision, easy to install, does not require electricity, can be automatically detected, can be visually inspected, and has low installation cost. This is another object of the present invention.

According to the present invention, the above-mentioned monitoring device preferably has two groups, one group is installed on the side of the bridge in the upstream direction, and the other group is installed on the side of the bridge in the backwater direction, even if one side is damaged, it can pass through the other side. The detection is alerted, and its multi-protection design can function even under serious damage. This is another object of the present invention.

According to the present invention, the height of the top of the gravity detection rod can be designed to be higher than a predetermined height of the bridge deck, and a warning cable will be connected between the tops of the gravity detection rod on the upstream side and the gravity detection rod on the backwater side, namely During the flood erosion, when the erosion reaches a dangerous level, the warning cable will descend with the subsidence of the river bed to warn, and further block the bridge deck to control the passage of people and vehicles to prevent accidental injuries. This is another object of the present invention.

According to the present invention, the monitoring device can be further equipped with a monitoring electrical signal acquisition unit, which is used to acquire the sliding distance between the gravity detection rod and the protective sleeve, and convert it into a digital signal and send it to the remote control center, and the received monitoring The electrical signal is compared with the data before the riverbed is scoured by the central processor, and if there is any abnormality in the analysis, the alarm system will be notified to issue an alarm, so as to play a remote monitoring function and further prevent accidental injuries. This is another object of the present invention.

Description of drawings

Figure 1a shows the real scene reference picture of general bridge piers and foundations after heavy rain or long-term erosion.

Figure 1b shows a schematic diagram illustrating the scour phenomena of general piers and foundations by fluid mechanics.

Fig. 2a shows a perspective view of the combined state of the monitoring device of the present invention; Fig. 2b is a schematic plan view of the sliding sleeve of the present invention; Fig. 2c is a schematic plan view of the protective sleeve of the present invention.

Fig. 3 a～Fig. 6 b illustrate the sectional schematic diagram of the specific embodiment of monitoring device of the present invention; Wherein, Fig. 3 a and 3 b show the sectional state schematic diagram of general water flow scouring; Fig. 4 a and 4 b show the section that protective casing is destroyed and deformed by floating stones etc. Schematic diagram of the state; Fig. 5a and 5b show the schematic diagram of the cross-sectional state of the protective sleeve and sliding sleeve being damaged and deformed by floating objects such as driftwood; Fig. 6a and 6b show the schematic diagram of the cross-sectional state of the monitoring device completely destroyed and deformed, and the gravity detection rod is also stuck .

Fig. 7 is a partial cross-sectional schematic diagram of an embodiment of a remote monitoring system according to the present invention.

8a and 8b are schematic block diagrams of remote monitoring in the embodiment of FIG. 7 .

Detailed ways

The technical characteristics of the present invention will be further described in conjunction with the following examples. This example is only a preferred representative example and is not used to limit the scope of the present invention. The best understanding can only be obtained by referring to the accompanying drawings in conjunction with the following detailed description .

First of all, please refer to Fig. 2a to Fig. 2c, which illustrate the specific embodiment of the present invention for monitoring the scour depth monitoring device of bridge foundation river bed, its main structure includes:

Gravity detection rod 1 has a scale 11 for indicating the scour depth on the surface of the rod member, and the lower end contains a disc-shaped abutting portion 12 that expands radially, which is used to abut against the river bed, and its upper end faces vertically. direction extension.

The protective casing 2 has an inner and outer double-layer structure, which has an inner casing 21 and an outer casing 22, and the two are connected into one body by a plurality of radially stiffened steel bars 23; the inner diameter of the inner casing 21 is larger than the gravity detection rod 1 outer diameter, for the gravity detection rod 1 to pass through and allow it to slide in the vertical direction, and the surface of the outer sleeve 22 is also provided with a scale 24 for indicating the flushing depth.

A plurality of sliding sleeves 3, one end of which has a guide part 31 loosely installed on the axial outer side of the protective sleeve 2, the inner diameter of the guide part 31 can allow the protective sleeve 2 to slide; the other end forms a number of support parts 32, Fixing components 33 such as bolts are respectively fixed on the pier 6 of the bridge or on other suitable structures of the bridge to maintain the protection sleeve 22 or the gravity detection rod 23 to slide vertically.

Fig. 3 a ~ Fig. 6 b are used for explaining the concrete embodiment that the monitoring device of the present invention is applied to the bridge, according to the present invention, the monitoring device that is made of above-mentioned gravity detecting rod 1, protective casing 2 and sliding sleeve 3 etc. preferably has Two groups, one set is installed on the side of the bridge facing the water direction, and the other set is installed on the side of the bridge facing the water direction. The material of the gravity detection rod 1 is, for example, a solid stainless steel material with high hardness and mechanical strength, or a hollow stainless steel material whose quality is sufficient to avoid deformation caused by instantaneous extrusion. Prevent the gravity detection rod 1 from excessively sinking in liquefied or soft soil. The inner sleeve 21, the outer sleeve 22 and the stiffening steel bar 23 etc. of the protective sleeve 2 are preferably made of high mechanical strength and ductility stainless steel materials; wherein, the stiffening between the inner sleeve 21 and the outer sleeve 22 The steel bar 23 has an energy-absorbing effect, so that even if the outer sleeve 22 is broken when it is hit instantly, the inner sleeve 21 can still be prevented from being directly damaged, and the function of the gravity detection rod 1 in the inner sleeve 21 can be guaranteed to function normally. 21 and the gravity detection rod 1 can also be selectively fixed together and move together. And, the optimal size of the protective sleeve 2 is designed in conjunction with the current situation data of flood erosion, and is designed by using finite element analysis method simulation; and, the bottom of the protective sleeve 2 should be able to touch the riverbed 8 at any time due to gravity surface, so that the gravity detection rod 1 can be completely protected from impact damage at any depth. In addition, at least two sliding sleeves 3 should be provided on the flood surface to protect and fix the casing 2 in the vertical direction, and maintain the gravity detection rod 1 and the protection casing 2 to slide down normally; and, each time After the flood it was able to be pulled out to check the function of the equipment.

According to the scouring simulation experiment of the present invention, generally can summarize following four scouring situations:

For example, as shown in Fig. 3a and Fig. 3b, it shows the state of general water flow washing. The gravity detection rod 1 can be completely covered by the protective sleeve 2 under normal water flow, and the inner sleeve 21 and the gravity detection rod 1 can freely slide up and down relative to each other. The surface scale 24 of the outer sleeve 22 of the tube 2, or the surface scale 11 of the gravity detection rod 1 is a reference value, and can be compared with the scale on the pier column to obtain the correct scour depth d.

Also as shown in Fig. 4a and Fig. 4b, it shows the state that the protective sleeve 2 is damaged and deformed by floating stones or the like. Under the scouring of small stones and drifts in the flood, the inner casing 21 and the gravity detection rod 1 cannot move relative to each other. When the sliding sleeve 3 is not damaged, the two sink at the same time. At this time, the correct scouring can be obtained by the relative displacement of the scale 24 of the outer sleeve 22 of the protective sleeve 2 or the scale 11 on the gravity detection rod 1 and the pier column. depth d.

As shown in Fig. 5a and 5b, it shows the state that the protection sleeve 2 and the sliding sleeve 3 are destroyed and deformed by floating objects such as driftwood. Under the scouring of floating objects such as driftwood and floating stones in the flood, if the outer casing 22 of the protective sleeve 2 is damaged, damaged and deformed by the floating stones, and the sliding sleeve 3 is also damaged, the protective sleeve 2 2 When it cannot sink with the scoured surface, the gravity detection rod 1 will sink to the scoured surface independently under the protection of the inner casing 21. At this time, the correct value can be obtained by comparing the scale 11 of the gravity detection rod 1 with the scale on the pier column. scour depth d.

As shown in Fig. 6a and Fig. 6b, in order to show that the monitoring device is completely crashed and deformed, the gravity detecting rod 1 is also stuck. Under the flood entrained earth-rock flow or huge rolling stone attack, the one side of the upstream surface including the sliding sleeve 3, the protective sleeve 2 and the gravity detection rod 1 can hardly operate, and the correct scouring can be obtained through the monitoring device on the other back surface Depth d, even the back-silting depth of soil and sand can be obtained from the differential subsidence on both sides.

In addition, in the above-mentioned embodiment, it can be designed that the height of the top of the gravity detection rod 1 is higher than the bridge deck 5 by a predetermined height, and will be located between the two tops of the gravity detection rod 1 on the upstream side and the gravity detection rod 1 on the backwater side. A warning cable 4 is connected, that is, in the process of flood scouring, when the scouring reaches a dangerous level, the warning cable 4 will descend and warn along with the subsidence degree of the river bed. In this way, when the disaster prevention center is unable to give real-time warnings to people and vehicles passing through the bridge due to telecommunications or traffic interruptions during typhoon storms, the above-mentioned simple bridge safety monitoring and control system can be used in severe environments. Not only is the structure simple, there is no maintenance problem, it reduces the monitoring manpower and there is no noise interference or disconnection. All passers-by on the bridge can directly detect the position of the gravity rod and the protective casing to prevent accidental injuries from happening before they happen. .

Figures 7 to 8b are used to illustrate another specific embodiment of the remote automatic monitoring system for monitoring the scour depth of the bridge foundation river bed according to the present invention. This embodiment mainly includes the monitoring device composed of the gravity detection rod 1 , the protective sleeve 2 and the sliding sleeve 3 , etc. The basic configuration is also the same as that of the above embodiment, so it will be briefly described without repeating it. But, the height of the gravity detecting rod 1 is not necessarily higher than the bridge deck, and can be configured in accordance with the shape of the bridge.

As shown in FIG. 7 , according to the present invention, it further includes: a monitoring signal acquisition unit 90 configured, for example, on the pier 6 of a bridge or on other suitable structures, and located beside the gravity detection rod 1 and the protective sleeve 2 side, and the height is on the predetermined scouring safety reference line, it is used to capture the data of the sliding distance of the gravity detection rod 1 or the protective sleeve 2, and convert it into an electrical signal and send it to the remote control center 91, and the received monitoring electrical signal The signal is processed and notified to the alarm system 92 .

According to the present invention, the monitoring signal acquisition unit 90 can be an optical type such as a camera, a light sensor, or an electrical type. As shown in FIG. 8a and FIG. 8b, it is an available electrical signal acquisition unit 90, which includes a group of resistance patches 901 arranged on the upper part of the gravity detection rod 1, which respectively have a pair of extraction terminals i, in and i, out, used to measure the current value flowing through the resistance sheet 901 during the drop, compare it with the reference current value flowing through the standard resistance sheet 902, and convert its relative value into an electrical signal and send it to the remote control center 91, such as a central processing unit be dealt with. That is to say, the change in the length of the measured resistance caused by the falling displacement of the gravity detection rod 1 can be converted into the scour depth d by comparing the ratio (I, _ref /I) of the read reference current to the measured current, For example:

If the reference resistance _R0 and the resistance R to be measured are connected in parallel with a current of equal intensity, the following relational formulas, formula (1) and formula (2) can be used to solve the drop d, cm caused by scouring:

(L ₀ -d)/L ₀ =R/R ₀ =I, _ref /I Formula (1)

d=L ₀ (1-(I, _ref /I)) Formula (2)

Therefore, the amount of drop d can be easily calculated from the read reference current, I, _ref and the value of the measured current I.

According to the present invention, the remote control center 91 compares the above-mentioned digital signal with the data before the river bed is scoured through a central processing unit, and if abnormality is analyzed, the alarm system 92 is notified to issue an alarm. In addition, the monitoring signal acquisition unit 90 can also cooperate with a monitoring camera to record video signals and send them to the remote control center 91 to directly read and monitor the scour depth data as a basis for disaster prevention and response.

In summary, compared with the traditional technology, the monitoring device and the remote automatic monitoring system for monitoring the scour depth of the bridge foundation river bed according to the present invention have the following advantages:

1. Simple structure: This device only uses three components (gravity detection rod, protective sleeve and guide groove).

2. Easy to assemble: All the materials used can be purchased in the market and assembled directly without special tools.

3. Easy maintenance: The equipment can be pulled out for inspection at any time, especially if damage is found before and after a typhoon, it can be replaced quickly.

4. No need for electricity: the equipment can be installed and used at any time, and can continuously monitor and flush in general harsh environments, without noise interference or disconnection problems.

5. Easy to interpret: no advanced technology is required, the position of the detection rod or the barrier of the horizontal "warning cable" can be used to understand the erosion situation without professional data interpretation.

6. Low cost: The materials used are only hundreds of thousands of yuan, which is much more economical than precision instruments with tens of millions of movements.

The above are only preferred embodiments of the present invention, and do not limit the implementation scope of the present invention. Any equivalent changes and modifications that do not deviate from the present invention should still fall within the scope of the present invention.

Claims (27)

1. A monitoring device for monitoring the scour depth of a bridge foundation river bed, characterized in that it comprises: At least one gravity detection rod, one end of which is in contact with the river bed, and the other end extends upward toward the vertical direction; At least one protective sleeve, the central part of which is passed by the gravity detection rod and allows the gravity detection rod to slide in the vertical direction; At least one sliding sleeve, one end of which is loosely sleeved on the outside of the sleeve, and the other end is fixed at a predetermined position of the bridge, is used to maintain at least one of the sleeve and the gravity detection rod to slide in the vertical direction. 2. The monitoring device as claimed in claim 1, wherein the gravity detection rod, the protective sleeve and the sliding sleeve preferably have two groups, one group is installed on the side of the bridge facing the water direction, and the other group is installed on the The side of the bridge facing away from the water. 3. The monitoring device according to claim 2, wherein the protective sleeve has an inner sleeve and an outer sleeve, the two are connected into one body by a plurality of stiffening steel bars, and the inner diameter of the inner sleeve allows the gravity detection The rod goes through and slides within it. 4. The monitoring device according to claim 3, wherein a plurality of scales for indicating the scour depth of the river bed are formed on the surface of the outer casing. 5. The monitoring device according to claim 1, wherein the protective sleeve is linked with the gravity detection rod. 6. The monitoring device as claimed in claim 3, wherein the inner casing, the outer casing and the reinforcing steel bars are made of stainless steel with high mechanical strength and ductility. 7. The monitoring device as claimed in claim 2, wherein the gravity detection rod is made of stainless steel with high hardness and mechanical strength. 8. The monitoring device according to claim 7, wherein the gravity detecting rod is solid or hollow. 9. The monitoring device according to claim 7, wherein a plurality of scales for indicating the scour depth of the river bed are formed on the surface of the outer diameter of the gravity detection rod. 10 . The monitoring device according to claim 7 , wherein the lower end of the gravity detection rod includes a disc-shaped abutting portion that expands radially to prevent excessive subsidence of the gravity detection rod in liquefied or soft soil. 11 . 11. The monitoring device according to claim 2, wherein the height of the top of the gravity detection rod is higher than that of the bridge deck, and a warning cable is connected between the two tops. 12. A bridge with monitoring function, characterized in that: The monitoring device according to any one of claims 1 to 11 is installed on the bridge, which is used to monitor the scour depth of the river bed. 13. A remote automatic monitoring system for monitoring the scour depth of a bridge foundation river bed, its features include: At least one gravity detection rod, one end of which is in contact with the river bed, and the other end extends vertically upwards to a set height; At least one protective sleeve, the central part of which is passed by the gravity detection rod and allows the gravity detection rod to slide in the vertical direction; At least one sliding sleeve, one end of which is loosely sleeved on the outside of the sleeve, and the other end is fixed at a predetermined position of the bridge, for maintaining at least one of the sleeve and the gravity detection rod to slide in the vertical direction; At least one monitoring signal acquisition unit is used to extract the electrical signal of the sliding distance of the gravity detection rod or the protection sleeve, and send it to a remote control center, process the received monitoring electrical signal and notify an alarm system. 14. The remote automatic monitoring system as claimed in claim 13, wherein the electrical signal is a digital signal. 15. The remote automatic monitoring system as claimed in claim 14, wherein the digital signal is compared with the data before the riverbed is scoured by a central processor, and if abnormality is analyzed, the alarm system is notified to issue an alarm. 16. The remote automatic monitoring system as claimed in claim 13, wherein the monitoring signal acquisition unit includes a group of resistance patches arranged on the upper part of the gravity detection rod, which respectively have a pair of extraction endpoints for measuring the falling Resistor sheet current, and its relative value is converted into an electrical signal and sent to the remote control center. 17. The remote automatic monitoring system as claimed in claim 13, wherein the monitoring signal acquisition unit further comprises a monitoring camera for recording video signals and sending them to the remote control center. 18. The remote automatic monitoring system as claimed in claim 13, wherein the gravity detection rod, the protective sleeve, the sliding sleeve and the monitoring signal acquisition unit preferably have two groups, and one group is installed on the side of the bridge in the direction of facing the water , and the other set is installed on the side of the bridge in the backwater direction. 19. The remote automatic monitoring system as claimed in claim 18, wherein the protective sleeve has an inner sleeve and an outer sleeve, the two are connected into one body by a plurality of stiffening steel bars, and the inner diameter of the inner sleeve allows the The gravity detection rod passes through and slides in it. 20. The remote automatic monitoring system as claimed in claim 19, wherein a plurality of scales for indicating the scour depth of the river bed are formed on the surface of the outer casing. 21. The remote automatic monitoring system according to claim 20, wherein, the protective sleeve is linked with the gravity detection rod. 22. The remote automatic monitoring system as claimed in claim 19, wherein the inner casing, the outer casing and the reinforcing steel bars are made of stainless steel with high mechanical strength and ductility. 23. The remote automatic monitoring system as claimed in claim 18, wherein the gravity detection rod is made of stainless steel with high hardness and mechanical strength. 24. The remote automatic monitoring system according to claim 23, wherein the gravity detecting rod is solid or hollow. 25. The remote automatic monitoring system as claimed in claim 24, wherein a plurality of scales for indicating the scour depth of the river bed are formed on the surface of the outer diameter of the gravity detection rod. 26. The remote automatic monitoring system as claimed in claim 25, wherein the lower end of the gravity detection rod includes a disc-shaped abutting portion that expands radially to prevent the gravity detection rod from excessively sinking in the liquefied or soft soil . 27. A bridge with automatic monitoring function, characterized in that: The remote automatic monitoring system according to any one of claims 13 to 26 is installed to monitor the scour depth of the river bed.

Images