Improved anti-falling assembly type overhaul well structure

Abstract

The utility model provides an improved anti-falling assembly type overhaul well structure, and particularly relates to the technical field of municipal engineering. In order to solve the problems that an existing overhaul well is insufficient in anti-falling protection, difficult to pass through, lack of monitoring and the like, the utility model provides an improved anti-falling assembly type overhaul well structure which comprises an overhaul well, the overhaul well and a drainage well are arranged in parallel, and a well communicated with the overhaul well and the drainage well is of a right-angle structure. An adjustable anti-falling net is mounted on the horizontal section of the hoistway; the adjustable anti-falling net comprises a supporting seat connected to the corner of the overhaul well; and the multiple telescopic protection rods are evenly arranged on the supporting base in the circumferential direction, and a lifting transverse rod is arranged at the bottom of each telescopic protection rod. According to the device, through the arrangement of the right-angle structure overhaul well, the adjustable anti-falling net and the monitoring equipment, comprehensive improvement of well safety protection, rapid maintenance and management is achieved.

Description

Technical Field

[0001] This utility model relates to the field of municipal engineering technology, specifically to an improved anti-fall prefabricated maintenance shaft structure. Background Technology

[0002] In urban drainage systems, drainage manholes serve as crucial infrastructure, responsible for the discharge of rainwater and sewage, as well as for inspection and maintenance. Traditional drainage manholes typically consist of a drainage manhole for drainage and a maintenance manhole for easy access by personnel. However, existing drainage manhole structures suffer from the following problems:

[0003] Firstly, traditional inspection wells are mostly designed as straight cylinders, lacking effective fall protection measures. If workers accidentally slip or tools fall during entry or operation, they can easily fall directly to the bottom of the well, causing personal injury or equipment damage, posing a significant safety hazard. This risk is especially high in deeper wells (e.g., over 4 meters), necessitating an effective fall protection structure to improve safety.

[0004] Secondly, traditional inspection well safety nets are mostly fixed designs. These nets consist of fixed-length rods or mesh panels, welded or bolted to the inner wall of the well shaft to intercept objects or personnel falling from the well opening, preventing them from entering the horizontal section or sewage well. However, this type of fixed safety net has significant limitations. First, fixed safety nets cannot be adjusted in height or disassembled. When maintenance personnel need to enter the sewage well for cleaning or maintenance, the safety net becomes an obstacle, preventing direct passage. They must detour or dismantle the entire net, a cumbersome and time-consuming operation, especially in narrow well environments (typically 0.8-1.5 meters in diameter). Dismantling fixed safety nets requires specialized tools, making it inefficient. Furthermore, traditional inspection wells lack flexible passage design, preventing maintenance personnel from quickly and safely passing through the safety net to reach the sewage well, affecting work efficiency and safety.

[0005] Finally, traditional drainage manholes lack effective monitoring methods. Harmful gases (such as hydrogen sulfide and methane) may accumulate inside drainage and maintenance manholes, or safety hazards may exist due to illegally opened manhole covers. However, existing manholes typically cannot monitor these anomalies in real time. Workers cannot accurately assess the environment inside the manhole before entering, increasing operational risks. Simultaneously, management departments cannot promptly detect problems such as opened manhole covers or excessive gas levels, resulting in slow emergency response, low management efficiency, and an inability to meet the safety requirements of modern urban drainage systems. Utility Model Content

[0006] In response to the aforementioned problems of insufficient fall protection, difficulty in passage, and lack of monitoring, this utility model aims to provide an improved prefabricated fall protection maintenance shaft structure. The device of this utility model achieves a comprehensive improvement in shaft safety protection, rapid maintenance, and management by setting up a right-angle structure maintenance shaft, an adjustable fall protection net, and monitoring equipment.

[0007] The main idea of ​​the technical solution adopted in this utility model is as follows: Firstly, addressing the insufficient fall protection of traditional manholes, a right-angled (L-shaped) inspection manhole is used, with an adjustable fall protection net installed at the corner to effectively intercept falling objects and protect the horizontal section. Secondly, addressing the difficulty of maintaining fixed fall protection nets, the adjustable fall protection net uses a telescopic protective rod design. It can be pushed and pulled up and down by lifting the crossbar, allowing personnel to pass through the net to reach the sewage well. Adjustment time for a single section is approximately 15 seconds, requiring no tools and supporting rapid maintenance. Finally, addressing the lack of monitoring, early warning devices are installed on the inner walls of the drainage well and inspection manhole. These devices, through detectors and communication power modules, monitor the manhole cover status and harmful gas concentration in real time, automatically triggering alarms and promptly addressing potential hazards.

[0008] The technical objective of this utility model is achieved through the following technical solution:

[0009] An improved fall-prevention prefabricated maintenance shaft structure includes a maintenance shaft, which is arranged in parallel with a drainage shaft. The shaft connecting the maintenance shaft and the drainage shaft is at a right angle, and an adjustable fall-prevention net is installed on the horizontal section of the shaft.

[0010] Adjustable fall protection nets include:

[0011] Support base, connected at the corner of the inspection well;

[0012] Multiple telescopic guardrails are evenly arranged on the support base along the circumference, and each telescopic guardrail has a lifting crossbar at its bottom.

[0013] To achieve the above technical solution, a further preferred solution is: the lifting crossbar includes:

[0014] The fixed base is fixedly connected to the lower part of the telescopic guard rod;

[0015] The rotating rod is mounted on the fixed base via a rotating connection, and the rotating rod is engaged with the adjacent telescopic guard rod.

[0016] Furthermore, the rotating rod end is provided with a snap-fit ​​component, and the adjacent telescopic guard rod is provided with a snap-fit ​​buckle at the corresponding position, and the snap-fit ​​component snaps into the snap-fit ​​buckle.

[0017] Furthermore, early warning devices are installed on the inner walls of both drainage wells and inspection wells.

[0018] Furthermore, the early warning device includes a detector and a communication and power module electrically connected to the early warning device. The detector is installed on the inner wall of the drainage well and the maintenance well, and the communication and power module is installed on the ground outside the maintenance well.

[0019] By adopting the above technical solution, this utility model has the following technical effects:

[0020] By installing right-angled inspection wells and adjustable fall protection nets, the safety and maintenance efficiency of drainage wells are improved. The right-angle design, combined with the fall protection net, effectively intercepts falling objects, protecting personnel from falling deeper. The telescopic safety bar allows personnel to pass through and reach the sewage well by pulling up and down the horizontal bar; no tools are required, operation is simple, and it is adaptable to the diameter of the well.

[0021] By setting up monitoring equipment, real-time monitoring of the opening status of manhole covers and the concentration of harmful gases is achieved. It can automatically detect abnormalities and issue alarms, ensuring the safe operation of drainage wells, promptly addressing potential safety hazards, and improving management efficiency and response speed. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly described below.

[0023] Figure 1 This is a schematic diagram of the overall structure of an improved anti-fall prefabricated maintenance shaft structure according to the present invention;

[0024] Figure 2 This is a schematic diagram of the communication energy module of this utility model;

[0025] Figure 3 This is a schematic diagram of the structure of the high-strength manhole cover of this utility model;

[0026] Figure 4 This is a schematic diagram of the adjustable fall protection net of this utility model. Figure 1 ;

[0027] Figure 5 This is a schematic diagram of the adjustable fall protection net of this utility model. Figure 2 ;

[0028] Figure 6 This is a schematic diagram of the lifting crossbar of this utility model;

[0029] Figure 7 This is a schematic diagram of the rotating rod of this utility model;

[0030] Figure 8 This is a schematic diagram of the snap-fit ​​mechanism of this utility model;

[0031] Figure 9This is a circuit design diagram for opening the manhole cover according to this utility model;

[0032] In the diagram, 1-drainage well; 2-inspection well; 21-handrail ladder; 3-high-strength manhole cover; 4-adjustable fall protection net; 41-support base; 411-horizontal bar; 412-vertical bar; 42-telescopic protective bar; 43-lifting horizontal bar; 431-fixed base; 432-rotating rod; 4321-clamping component; 433-clamping buckle; 51-detector; 52-communication energy module; 521-solar panel; 522-communication antenna; 523-adjusting rod; 5231-support rod; 5232-hinged component; 5233-rotating component. Detailed Implementation

[0033] The technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments, not all embodiments.

[0034] refer to Figure 1-9 This application discloses an improved prefabricated structure for a fall-prevention drainage well 1, including a maintenance well 2, which is arranged parallel to the drainage well 1. A high-strength well cover 3 is installed on the top of the drainage well 1. The well channel connecting the maintenance well 2 and the drainage well 1 is at a right angle, and an adjustable fall-prevention net 4 is installed on the horizontal section of the well channel. Warning devices are installed on the inner walls of the drainage well 1 and the maintenance well 2.

[0035] like Figure 3 The top of the drainage well 1 is equipped with an integrated high-strength manhole cover 3. The manhole cover is designed to be non-openable and is made of high-strength metal or composite materials. It can withstand the pressure of traffic flow, pedestrians, and impacts from external objects, preventing accidental opening and ensuring the safety of the drainage well 1. The manhole cover has a tight structure and is not easily opened by external force, avoiding traffic safety hazards caused by loose or opened manhole covers.

[0036] Specifically, Inspection Manhole 2 is located next to and parallel to Drainage Manhole 1. It is situated within a greenbelt area alongside city streets or sidewalks. The tops of Inspection Manhole 2 are covered by soil and vegetation from the greenbelt, completely concealing the manhole body and cover from view. This design effectively prevents unauthorized personnel from entering the manhole area. The natural concealment by vegetation also avoids direct contact with the manhole, especially in densely populated areas, reducing the risk of pedestrians unintentionally approaching the manhole cover.

[0037] Specifically, the manhole of inspection well 2 adopts a right-angle turn design, i.e., an L-shaped design, including a vertical section starting from the entrance and a horizontal section turning at the corner. The vertical section extends downward from the top entrance of the manhole near the high-strength manhole cover 3, with a depth of 4 meters; at the corner, the manhole turns horizontally, forming a horizontal section with a length of 3 meters, the end of which connects to drainage well 1. The cross-section of the manhole is circular with a diameter of 1.2 meters, and the inner wall of the manhole is made of concrete with a waterproof coating to enhance durability.

[0038] Preferably, a handrail ladder 21 is installed on the vertical wall of the maintenance shaft 2. The ladder is made of corrosion-resistant metal or synthetic material, capable of withstanding the weight and operating force of municipal personnel during maintenance. The ladder is designed as a stepped ladder with sturdy handrails, facilitating access for municipal personnel within the shaft and ensuring safety when entering and exiting. The handrails are positioned at an appropriate height, conforming to ergonomic principles, allowing workers to easily grip them and ensuring no accidents occur during maintenance.

[0039] like Figure 1 The adjustable fall arrestor net 4 is installed at the right-angle corner of the inspection well 2 shaft, that is, at the junction of the bottom of the vertical section and the starting point of the horizontal section. The fall arrestor net is placed horizontally, covering the entire shaft cross-section, and its center height is located at the bottom of the vertical section, that is, at a shaft depth of 4 meters, to ensure that it can intercept objects or personnel falling from the vertical section and prevent them from entering the horizontal section or impacting the corner structure.

[0040] Specifically, the adjustable fall protection net 4 includes: a support base 41 connected to the corner of the inspection well; multiple telescopic guard rods 42 evenly arranged on the support base 41 along the circumference, and each telescopic guard rod 42 has a lifting crossbar 43 at its bottom.

[0041] like Figure 4 The support base 41 is a circular frame structure made of 304 stainless steel, which is corrosion-resistant and suitable for the humid environment of the well. The outer diameter of the support base 41 matches the diameter of the well. The outer side of the support base 41 has four 10mm diameter mounting holes for fixing to the inner wall at the corner of the inspection well 2 well using expansion bolts. The inner side of the support base 41 has nine fixing points along the circumference for connecting the telescopic protective rod 42.

[0042] Specifically, the support base 41 also includes horizontal bars 411 and vertical bars 412. Multiple horizontal bars 411 are horizontally welded to the upper part of the telescopic protective bar 42 to enhance structural rigidity. Two vertical bars 412 are stacked and welded to the inner surface of the support base 41.

[0043] Specifically, there are nine telescopic protective rods 42, which are evenly arranged on the support base 41 along the vertical direction of the circumference. The telescopic protective rods 42 are made of 304 stainless steel and consist of an outer tube and an inner rod: the top of the outer tube is fixed to the inside of the support base 41 by welding.

[0044] Preferably, the outer rod is made of 304 stainless steel, which is corrosion-resistant and suitable for the humid environment of the shaft. The outer rod has a cylindrical hollow structure, is 30 cm long, and weighs approximately 0.3 kg. The top of the outer rod is fixed to the inside of the support base 41 by welding. The inner wall of the outer rod is smooth, and there are 5 positioning holes on the inner side for fixing the first layer of inner rods.

[0045] Specifically, the first inner rod is also made of 304 stainless steel. This first inner rod can extend and retract within the outer rod, with its extension length ranging from 0-30 cm, limited by the positioning holes on the outer rod. The outer side of the first inner rod has a 4.8 mm diameter spring positioning pin, which can be inserted into the positioning holes on the outer rod to fix its position. The inner wall of the first inner rod has five 5 mm diameter positioning holes spaced 5 cm apart, used to fix the second inner rod.

[0046] Preferably, the second inner rod is made of 304 stainless steel and is 40 cm long. The second inner rod can extend and retract within the first inner rod, with an extension length ranging from 0 to 35 cm. A 4.8 mm diameter spring-loaded positioning pin is provided on the outer side of the second inner rod, which can be inserted into the positioning hole of the first inner rod to fix its position. A lifting crossbar 43 is provided at the bottom of the second inner rod.

[0047] Preferably, the lifting crossbar 43 includes: a fixed base 431, which is fixedly connected to the lower part of the telescopic protective bar 42; and a rotating rod 432, which is mounted on the fixed base 431 by a rotating connection and is engaged with the adjacent telescopic protective bar 42.

[0048] Preferably, the lifting crossbar 43 is provided at the lower part of each telescopic guard bar 42. The adjustable fall protection net 4 includes 9 telescopic guard bars 42, so there are a total of 9 lifting crossbars 43. The lifting crossbar 43 includes a fixed base 431, a rotating rod 432, and a snap fastener 433.

[0049] Preferably, the fixing seat 431 is a circular rod-shaped structure made of 304 stainless steel, which is corrosion-resistant and suitable for the humid environment of the well. The horizontal section of the fixing seat 431 is welded to the bottom of the second inner rod of the telescopic protective rod 42. The end of the fixing seat 431 is provided with a "U"-shaped groove, and a hole is opened through the lower part of the "U"-shaped groove. A rotating shaft is connected to the through hole, and a rotating rod 432 is rotatably connected to the rotating shaft.

[0050] Specifically, the rotating rod 432 has a cylindrical structure. One end of the rotating rod 432 is rotatably connected to the fixed base 431 via a rotating shaft, and can rotate around the fixed base 431 with a rotation angle range of 0-90 degrees. The other end of the rotating rod 432 is provided with a snap-fit ​​component 4321.

[0051] like Figure 7 The snap-fit ​​component 4321 has a hook-shaped structure, is made of 304 stainless steel, and is integrally formed with the rotating rod 432. The hook part of the snap-fit ​​component 4321 is L-shaped, and the end of the hook arm is slightly tapered inward to form a semi-closed hook opening, which facilitates engagement into the U-shaped groove of the snap-fit ​​buckle 433. The surface of the snap-fit ​​component 4321 is smooth, reducing friction during engagement and ensuring smooth operation.

[0052] like Figure 8 The snap-fit ​​buckle 433 is located at the bottom of the second inner pole below the adjacent telescopic guardrail 42. The snap-fit ​​buckle 433 has a double-sided lug structure, is made of 304 stainless steel, and is integrally formed with the telescopic guardrail 42 or fixed by welding. The snap-fit ​​buckle 433 consists of two symmetrical lugs, the distance between which is slightly larger than the hook width of the snap-fit ​​component 4321. The outer side of the lug is flat, and the inner side faces the groove with an arc radius of 1.1 mm, facilitating the engagement of the hook of the snap-fit ​​component 4321. The hook of the snap-fit ​​component 4321 can engage in the U-shaped groove of the snap-fit ​​buckle 433, and the curved design at the end of the hook arm ensures that it is not easily dislodged after engagement.

[0053] like Figure 2 The early warning device 5 consists of two main parts: a detector 51 and a communication and power module 52. The detector 51 is installed on the inner wall of the drainage well 1 and the inspection well 2, and is connected to the communication and power module 52 wirelessly or via wired connection. The main function of the detector 51 is to monitor the condition inside the well in real time, detect whether the well cover is open, and monitor the concentration of harmful gases such as methane and hydrogen sulfide inside the well. Based on the detection results, the detector 51 can determine whether there are any safety hazards and transmit the data to the municipal monitoring platform.

[0054] Detector 51 uses the TA-100 portable four-in-one gas detector alarm, a portable high-precision gas detector with a built-in miniature sampling pump. The instrument comes standard with 3000 historical data storage capabilities, allowing users to view historical data through lists or graphs. An optional large-capacity data storage function allows users to read historical records from the instrument via computer for printing, exporting, and analysis. Gas concentration values ​​can be displayed in PPM and mg / m³. 3 It can switch between multiple concentration units; the color LCD display technology supports graphic descriptions; and the Chinese and English operation interfaces can be switched.

[0055] Product Features: Employs a high-precision sensor; features a built-in miniature sampling pump with ten adjustable suction levels; includes 3000 historical data points, displayable via data lists or graphs; utilizes a color LCD display to show gas name, unit, concentration, time, and other parameters; supports both Chinese and English operating interfaces for easy switching; gas concentration units are ppm and mg / m³. 3 Display can be quickly switched; Big data storage (optional): 1. Supports storage of 260,000 historical records; 2. Convenient continuous and segmented storage with adjustable storage interval; 3. Equipped with professional visualization data analysis software.

[0056] Product Parameters: Battery: 7.4V lithium-ion rechargeable battery; Measurement Accuracy: <±3% (FS); Display: Color LCD display; Operating Language: Chinese, English; Operating Temperature: -20℃~50℃; Operating Humidity: 0~95%RH; Alarm Method: Level 2 audible and visual alarm; Working Time: 9-10 hours for toxic gases and 5 hours for combustible gases with the pump running; Dimensions: 210mm*75mm*32mm; Weight: 400g

[0057]

[0058]

[0059] Manhole cover inspection can be achieved using magnetic switches or micro switches (see...) Figure 9 ).

[0060] Magnetic switch: When the manhole cover is closed, the magnetic switch is in the closed state, and the microcontroller detects a low-level signal; when the manhole cover is opened, the magnetic switch is open, and the microcontroller detects a high-level signal.

[0061] Pull-up resistor: Ensures that the microcontroller can reliably detect a high-level signal when the magnetic switch is off.

[0062] The microcontroller (such as STM32 or STC89C52) needs to process the signals from the manhole cover detection module:

[0063] When a manhole cover open signal (high level) is detected, the display shows "Manhole cover open" status and can trigger the alarm module to issue an alarm. When a manhole cover closed signal (low level) is detected, the display shows "Manhole cover closed" status.

[0064] Preferably, the detector has a built-in high-precision sensor that can monitor the opening status of the manhole cover and the gas concentration inside the manhole in real time. When the manhole cover is accidentally opened or the gas concentration exceeds the set safety value, the detector 51 can detect it in time and transmit the data to the communication power module 52, ensuring that the communication power module 52 can immediately issue an alarm. By interfacing with the municipal monitoring platform, the detector 51 can remotely and promptly display the safety status of the manhole.

[0065] Preferably, the communication power module 52 is installed on the ground outside the inspection well 2. Its model is EnOcean STM 550, and it mainly includes a solar panel 521 and a communication antenna 522. The solar panel 521 is mounted on the ground near the well cover via a bracket, and is responsible for providing the necessary power to the entire early warning device 5. The communication antenna 522 is mounted on the solar panel 521, and an adjustment rod 523 is provided at the lower part of the solar panel 521.

[0066] The adjusting rod 523 consists of a support rod 5231, a hinge 5232, and a rotating component 5233. The support rod 5231 is a sturdy metal rod, its bottom fixed to the ground, and the hinge 5232 welded to its top. The hinge 5232 is made of high-strength alloy material and is a hinge structure with a rotating shaft, ensuring flexible and stable rotation. The rotating component 5233 is connected to the hinge 5232 via a rotating shaft, allowing it to rotate freely within a certain angle range. Its other end is securely connected to the bottom frame of the solar panel 521 by bolts or welding. The solar panel 521's tilt angle is adjusted by rotating the rotating component 5233, allowing for angle adjustments in different seasons or at different times of day to maximize light energy absorption efficiency.

[0067] It is worth noting that the communication antenna 522 connects to the detector 51 and the municipal monitoring platform, providing a stable signal transmission channel. The communication antenna 522 remotely transmits real-time data from the detector 51 to the municipal monitoring center via wireless or wired means. Municipal staff can check the safety status of the manhole at any time through the monitoring platform. In the event of emergencies such as an open manhole cover or abnormal gas concentration, the monitoring platform will promptly issue an alarm and guide staff in handling the situation.

[0068] Preferably, the design of drainage well 1 and inspection well 2 incorporates a reasonable elevation difference to ensure the effective operation of the drainage system. Specifically, the elevation of the sewage area within drainage well 1 is designed to be lower than the elevation of the corner of inspection well 2, forming a natural gravity drainage channel to ensure that sewage can flow smoothly from drainage well 1 into the municipal drainage network through the pipes. This elevation difference design effectively prevents sewage backflow and avoids sewage from entering inspection well 2 or other drainage facilities due to rising water levels.

[0069] The workflow of this embodiment is as follows:

[0070] First, install an adjustable fall protection net 4 at the right-angle corner of the inspection well 2. Secure the support base 41 to the inner wall of the well with four expansion bolts (1.2 meters in diameter). Install nine telescopic protective rods 42. Pull down the lifting crossbar 43 to extend the telescopic protective rods 42 to the bottom, and engage the locking piece 4321 with the locking buckle 433 to form a protective mesh. When opening is required, rotate the rotating rod 432 to disengage the locking piece 4321 from the locking buckle 433, and pull up the lifting crossbar 43 to facilitate access for maintenance personnel to the sewage well.

[0071] Next, detectors 51 are installed on the inner walls of drainage well 1 and inspection well 2, communication and energy modules 52 are placed on the ground next to the manhole cover, solar panels 521 are adjusted to 30 degrees by adjusting rods 523, the system is initialized, and connected to the municipal monitoring system.

[0072] Drainage well 1 drains water normally, while inspection well 2 serves as an inspection passage. Fall protection net 4 intercepts debris such as leaves and gravel falling from the vertical section, protecting the drainage function of the horizontal section. The early warning device 5's detector 51 monitors the manhole cover's open status and the concentration of harmful gases such as hydrogen sulfide in real time. The data is transmitted to the management center via communication and energy module 52, with a monitoring frequency of once every 5 minutes.

[0073] It should be understood that the above detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. An improved anti-falling assembly type inspection shaft structure, comprising an inspection shaft (2) which is arranged in parallel with a drainage well (1), characterized in that ； The well connecting the inspection well (2) and the drainage well (1) is at a right angle, and an adjustable fall protection net (4) is installed on the horizontal section of the well. The adjustable fall protection net (4) includes: Support base (41) is connected at the corner of the inspection well; Multiple telescopic guardrails (42) are evenly arranged on the support base (41) along the circumferential direction, and each telescopic guardrail (42) has a lifting crossbar (43) at its bottom.

2. The improved anti-falling assembly type inspection shaft structure according to claim 1, characterized in that, The lifting bar (43) includes: Fixed base (431), fixed base (431) is fixedly connected to the lower part of telescopic guard rod (42); The rotating rod (432) is mounted on the fixed base (431) by means of rotational connection, and the rotating rod (432) is engaged with the adjacent telescopic guard rod (42).

3. The improved anti-falling assembly type inspection shaft structure according to claim 2, characterized in that, The end of the rotating rod (432) is provided with a snap-fit ​​piece (4321), and the adjacent telescopic guard rod (42) is provided with a snap-fit ​​buckle (433) at the corresponding position. The snap-fit ​​piece (4321) and the snap-fit ​​buckle (433) snap together.

4. The improved anti-falling assembly type inspection shaft structure according to claim 1, wherein, Both the drainage well (1) and the maintenance well (2) are equipped with early warning devices (5).

5. The improved fall-prevention assembled inspection shaft structure according to claim 4, characterized in that, The early warning device (5) includes a detector (51) and a communication power module (52) connected thereto. The detector (51) is installed on the inner wall of the drainage well (1) and the maintenance well (2), and the communication power module (52) is installed on the ground outside the maintenance well (2).

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