A foundation pit control point monitoring device

Abstract

The utility model relates to the field of building construction technology discloses a kind of foundation pit control point monitoring devices, comprising: crown beam, is set to both sides of foundation pit;Supporting beam, supporting beam is connected with crown beam, is set to the top of foundation pit, crown beam and supporting beam are jointly built to form measurement platform, measurement platform is used to arrange laser receiving plate and erect prism, to realize the guidance and measurement of the control point to be measured in foundation pit;Ground control point, ground control point is set to ground outside foundation pit, ground control point is provided with total station, total station is positioned control point to be measured in foundation pit by prism and laser receiving plate cooperation. Foundation pit control point monitoring device builds measurement platform by crown beam and supporting beam, measurement platform is directly relied on original crown beam and supporting beam of foundation pit to build, both ensure structural stability, and avoid the damage to foundation pit main body. The cooperation of laser receiving plate and prism ensures the high-precision transmission from ground reference to control point in foundation pit.

Description

Technical Field

[0001] This utility model relates to the field of building construction technology, specifically to a foundation pit control point monitoring device. Background Technology

[0002] The establishment and calibration of control points within the excavation pit are crucial core steps in excavation pit construction surveying. Their purpose is to establish a high-precision, stable surveying benchmark network within the pit. This ensures that all subsequent construction layout is based on a reliable and error-free surveying benchmark, thereby guaranteeing project quality and construction safety.

[0003] The establishment of control points inside existing municipal foundation pits typically uses stable positioning piles on the ground outside the pit as a reference. Vertical measurement is carried out using a plumb line, which requires suspending a steel wire rope at the pit opening with a weight hanging from the end. After aligning the weight with the ground reference point, it is allowed to hang freely to the bottom of the pit, thus establishing a control point on the ground inside the pit. Alternatively, a projection method using pre-drilled holes can be used. Openings are pre-drilled in the floor slab, and a laser plumb line is used to transfer the control points from the bottom floor to the construction floors. However, the plumb line is easily affected by airflow caused by ventilation and mechanical disturbances inside the pit, making it difficult to stabilize the steel wire rope. This method places extremely high demands on observation conditions and collaborative operations. Furthermore, pre-drilled holes in building construction require openings in the structural floor slab, which not only damages the integrity of the floor slab and poses safety hazards, but also makes the openings susceptible to obstruction or damage from falling objects during construction. In addition, the vertically visible openings can become airflow channels, interfering with the beam path of the laser plumb line to some extent. Utility Model Content

[0004] In view of this, the present invention provides a foundation pit control point monitoring device to solve the problems of cumbersome measurement and monitoring process and inconvenient construction.

[0005] This utility model provides a foundation pit control point monitoring device, comprising:

[0006] Cap beams are installed on both sides of the foundation pit;

[0007] The support beam is connected to the capping beam and is set at the top of the foundation pit. The capping beam and the support beam together form a measurement platform. The measurement platform is used to arrange the laser receiving plate and set up the prism to realize the guidance and measurement of the control points to be measured in the foundation pit.

[0008] Ground control points are set on the ground outside the foundation pit. Each ground control point is equipped with a total station, which uses a prism and a laser receiver to locate the control points to be measured inside the foundation pit.

[0009] Beneficial Effects: The foundation pit control point monitoring device, by constructing a measurement platform using the capping beam and support beams, solves the problems of existing technologies such as the plumb line method being susceptible to wind interference and the pre-drilled holes method damaging structural integrity. The measurement platform is directly constructed based on the existing capping beam and support beams of the foundation pit, eliminating the need for additional temporary structures, thus ensuring structural stability and avoiding damage to the main body of the foundation pit. The total station at the ground control points uses a prism and laser receiving plate for positioning, achieving precise guidance and measurement of the control points to be measured within the foundation pit, reducing the impact of environmental factors on measurement accuracy. Centralizing measurement operations on the platform reduces the manpower required for collaborative work inside and outside the foundation pit, eliminating the need for two separate teams to simultaneously observe inside and outside the pit, significantly improving measurement efficiency. Simultaneously, the combined use of the laser receiving plate and prism ensures high-precision transmission from the ground benchmark to the control points within the foundation pit, providing a reliable benchmark for subsequent construction layout and effectively guaranteeing project quality and construction safety.

[0010] In one alternative implementation, the measurement platform includes a one-way slab platform and a cantilever slab platform, each with different span structures to accommodate different support beam layouts.

[0011] Beneficial Effects: The measurement platform, comprising one-way slab and cantilever slab platforms with varying spans, significantly enhances the system's applicability and flexibility. The layout of support beams in municipal foundation pits varies depending on project scale and geological conditions. One-way slab and cantilever slab platforms of different spans can be flexibly adapted to the spacing and distribution of the support beams without requiring adjustments to the existing support beam structure. This not only reduces the complexity of platform design and construction but also minimizes measurement errors caused by mismatches between the platform and support beams. It ensures stable placement of the laser receiving plate and prism under various working conditions, providing a foundation for high-precision measurements and saving time and costs associated with designing separate platforms for different foundation pits.

[0012] In one alternative implementation, a laser plumb bob is installed at the control point to be measured within the foundation pit to transmit laser signals to a laser receiving board.

[0013] Beneficial effects: The addition of a laser plumb line further improves the positioning accuracy and efficiency of the control points to be measured within the foundation pit. The laser signal emitted by the laser plumb line has strong directionality and anti-interference capabilities, and can stably transmit the position information of the control points to be measured within the foundation pit. The laser plumb line is positioned at the control point to be measured and emits laser light directly into the laser receiving plate of the measurement platform, reducing errors from manual observation and avoiding uncertainties caused by the swaying of the steel wire rope.

[0014] In one optional implementation, a laser receiving plate is positioned at the projection position of the control point to be measured along the direction of gravity onto the measuring platform, and the laser receiving plate is used to receive the laser signal projected by the laser plumb line.

[0015] Beneficial effects: Positioning the laser receiver plate at the projection location of the control point under test along the direction of gravity ensures the vertical correspondence of the laser signal transmission and reduces vertical positioning deviation. With the laser receiver plate and the control point on the same vertical line, the laser emitted by the laser plumb line can be directly projected onto the corresponding position on the receiver plate, avoiding signal misalignment caused by positional offset. This allows the laser signal to accurately reflect the vertical coordinates of the control point, providing a reference for subsequent total station measurements using a prism and improving vertical positioning accuracy.

[0016] In one alternative implementation, the prism is positioned above the laser receiving plate and works in conjunction with the total station to perform closed traverse measurements.

[0017] Beneficial effects: By positioning the prism directly above the laser receiver and using it in conjunction with a total station for closed traverse surveying, the overall measurement accuracy of the system is improved. Closed traverse surveying is a method in engineering surveying that ensures accuracy. By forming a closed loop through multiple observations, random errors can be effectively offset. The corresponding positions of the prism and the laser receiver allow the prism coordinates observed by the total station to be directly correlated with the vertical positioning information received by the laser receiver, ensuring a perfect match between the horizontal measurement reference and the vertical positioning reference, and avoiding cumulative errors caused by their disconnection.

[0018] In one alternative implementation, a fence is provided at the edge of the measuring platform to ensure the safety of the measuring personnel.

[0019] Beneficial effects: The installation of a fence around the edge of the surveying platform provides safety for surveying operations and solves the safety hazards associated with working at heights in the foundation pit. The fence effectively prevents personnel from accidentally falling and equipment from dropping, thus creating a physical safety barrier.

[0020] In one alternative implementation, the ground control points are also retained as verification benchmarks for calibrating the measurement results on the measurement platform.

[0021] Beneficial effects: Retaining ground control points as verification benchmarks provides an effective calibration method for the measurement platform's results, improving the reliability of the measurement system. During foundation pit construction, the measurement platform may shift position due to factors such as foundation pit settlement and support beam deformation. Relying solely on the measurement results from the platform may lead to accumulated errors that go undetected. Ground control points, as stable benchmarks independent of the platform, allow for periodic verification of the measurement data from the platform, enabling timely detection and calibration of deviations by comparing the two results.

[0022] In one alternative implementation, the measuring platform is integrally cast with the cap beam and support beam.

[0023] Beneficial effects: The measurement platform, capping beam, and support beams are constructed as a single, integrated cast-in-place structure, enhancing the platform's structural stability and load-bearing capacity, and effectively extending the system's service life. The integrated cast-in-place structure is formed in one step during construction, with the capping beam, support beams, and measurement platform forming a continuous, integrated load-bearing system. This ensures even load distribution and avoids structural damage caused by localized stress concentration. Furthermore, the integrated casting reduces subsequent installation steps, saving labor and time costs, and preventing secondary damage to the capping beam and support beams during installation.

[0024] In one alternative implementation, the total station is fixed to the ground control point via a detachable connector, which has a leveling adjustment structure for calibrating the levelness of the total station setup.

[0025] Beneficial effects: The total station is fixed to the ground control points via detachable connectors with a leveling adjustment mechanism, which improves the installation flexibility of the total station while ensuring the horizontal accuracy of the measurement. The leveling adjustment mechanism can accurately calibrate the levelness of the total station, solving the problem of instrument deviation caused by slight tilting of the ground control points.

[0026] In one alternative embodiment, a reinforcing rib is provided at the connection node between the cap beam and the support beam, and the reinforcing rib is evenly distributed around the perimeter of the node.

[0027] Beneficial effects: The uniformly distributed reinforcing ribs at the connection points between the capping beam and the supporting beam enhance the structural strength and deformation resistance of the joint, ensuring the stability of the measurement platform. The even distribution of the reinforcing ribs around the joint effectively disperses stress, improving the joint's shear and bending resistance and preventing structural damage caused by excessive localized stress. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the foundation pit control point measurement platform of this utility model;

[0030] Figure 2 This is a top view of the foundation pit control point measurement platform of this utility model;

[0031] Figure 3 This is a schematic diagram of an existing foundation pit control point monitoring device;

[0032] Figure 4This is a schematic diagram of the foundation pit control point monitoring device of this utility model;

[0033] Figure 5 This is a schematic diagram of the measurement platform A of this utility model;

[0034] Figure 6 This is a schematic diagram of the measurement platform B of this utility model.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Crown beam; 2. Measurement platform; 3. Control point to be measured; 4. Support beam; 5. Total station; 6. Prism; 7. Laser plumb line; 8. Laser receiving plate. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of 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 of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0038] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0040] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0041] The establishment and calibration of control points within the excavation pit are core aspects of excavation pit construction surveying. Their purpose is to construct a high-precision and stable measurement benchmark network within the pit, providing a reliable basis for all subsequent construction layout, thereby ensuring project quality and construction safety. Currently, combined with... Figure 3 As shown, the establishment of control points inside municipal foundation pits is usually based on stable positioning piles on the ground outside the pit. The main method used for vertical measurement is the plumb line method, where a steel wire rope is suspended from the pit opening with a weight at the end, aligned with the ground reference point, and then allowed to hang freely to the bottom of the pit to establish control points on the ground inside. Alternatively, a pre-drilled hole method can be used, where openings are pre-drilled in the structural floor slab, and a laser plumb line is used to transfer control points from the bottom layer upwards. However, the plumb line method is easily affected by airflow from ventilation and mechanical disturbances within the pit, making it difficult to stabilize the steel wire rope and requiring high levels of observation conditions and coordinated operation. The pre-drilled hole method not only damages the structural integrity of the floor slab and poses safety hazards, but the openings are also easily obstructed or damaged by falling objects during construction. Furthermore, the vertically visible openings create airflow channels that may interfere with the beam path of the laser plumb line.

[0042] The following is combined with Figures 1 to 6 The following describes embodiments of the present invention.

[0043] According to an embodiment of this utility model, a foundation pit control point monitoring device is provided, comprising: a capping beam 1, disposed on both sides of the foundation pit; a support beam 4, connected to the capping beam 1 and disposed at the top of the foundation pit, the capping beam 1 and the support beam 4 together forming a measurement platform 2, the measurement platform 2 being used to arrange a laser receiving plate 8 and erect a prism 6 to guide and measure the control point 3 to be measured within the foundation pit; and a ground control point, disposed on the ground outside the foundation pit, the ground control point being equipped with a total station 5, the total station 5 using the prism 6 and the laser receiving plate 8 to locate the control point 3 to be measured within the foundation pit.

[0044] The foundation pit control point monitoring device uses a measurement platform 2 constructed from the capping beam 1 and support beam 4, solving the problems of existing technologies such as the plumb line method being susceptible to wind interference and the pre-drilled hole method damaging structural integrity. The measurement platform 2 is directly constructed based on the existing capping beam 1 and support beam 4 of the foundation pit, eliminating the need for additional temporary structures, thus ensuring structural stability and avoiding damage to the main body of the foundation pit. The total station 5 of the ground control point is positioned using a prism 6 and a laser receiving plate 8, achieving precise guidance and measurement of the control point 3 to be measured within the foundation pit, reducing the impact of environmental factors on measurement accuracy. Centralizing the measurement operations on the platform reduces the manpower required for collaborative work inside and outside the foundation pit, eliminating the need for two separate teams to observe simultaneously inside and outside the pit, significantly improving measurement efficiency. Simultaneously, the combined use of the laser receiving plate 8 and prism 6 ensures high-precision transmission from the ground benchmark to the control point within the foundation pit, providing a reliable benchmark for subsequent construction layout and effectively guaranteeing project quality and construction safety.

[0045] Furthermore, the ground control points are also retained as verification benchmarks for calibrating the measurement results on measurement platform 2. Retaining the ground control points as verification benchmarks provides an effective means of calibrating the measurement results of measurement platform 2, improving the reliability of the measurement system. During the foundation pit construction process, measurement platform 2 may experience positional shifts due to factors such as foundation pit settlement and deformation of support beam 4. Relying solely on the measurement results on the platform may lead to the accumulation of errors that go undetected. As stable benchmarks independent of the platform, the ground control points can periodically verify the measurement data on the platform, allowing for timely detection and calibration of deviations by comparing the two results.

[0046] It is worth noting that reinforcing ribs are provided at the connection node between the capping beam 1 and the support beam 4, and these ribs are evenly distributed around the perimeter of the node. The evenly distributed reinforcing ribs at the connection node enhance the structural strength and deformation resistance of the node, ensuring the stability of the measurement platform 2. The even distribution of the reinforcing ribs around the node effectively disperses stress, improves the shear and bending resistance of the node, and prevents structural damage caused by excessive local stress.

[0047] In some embodiments, combined with Figure 2 As shown, the measurement platform 2 includes a one-way slab platform and a cantilever slab platform, each with different span structures to accommodate different support beam 4 layouts. The inclusion of both one-way slab and cantilever slab platforms with varying span structures significantly enhances the system's applicability and flexibility. The layout of the support beam 4 in municipal foundation pits varies due to differences in project scale and geological conditions. One-way slab and cantilever slab platforms with different spans can be flexibly adapted to the spacing and distribution of the support beam 4 without requiring adjustments to the original support beam 4 structure. This not only reduces the complexity of platform design and construction but also minimizes measurement errors caused by mismatch between the platform and the support beam 4, ensuring stable placement of the laser receiving plate 8 and prism 6 under various working conditions. This provides a foundation for high-precision measurement and saves time and cost associated with designing separate platforms for different foundation pits.

[0048] Specifically, in combination Figure 5 and Figure 6 As shown, one-way slabs and cantilevered reinforced concrete platforms are arranged on support beam 4 and capping beam 1. The load-bearing capacity is calculated to fully consider personnel movement, the stress on the concrete supports, and personnel safety. The concrete strength is B30, and the steel reinforcement strength is A500. The concrete slab is 200mm thick, with a static load of 5kPa and a live load of 3kPa. Measurement platform A is a 2.13-meter span one-way slab, and measurement platform B is a 2.20-meter span cantilever slab.

[0049] In some embodiments, combined with Figure 2As shown, the laser plumb bob 7 is installed at the control point 3 to be measured within the foundation pit, and is used to transmit laser signals to the laser receiving plate 8. The addition of the laser plumb bob 7 further improves the positioning accuracy and efficiency of the control point 3 to be measured within the foundation pit. The laser signal emitted by the laser plumb bob 7 has the characteristics of strong directionality and strong anti-interference ability, and can stably transmit the position information of the control point 3 to be measured within the foundation pit. The laser plumb bob 7 is installed at the control point 3 to be measured and directly transmits laser to the laser receiving plate 8 of the measurement platform 2, reducing the error of manual observation and avoiding the uncertainty caused by the swaying of the steel wire rope.

[0050] Furthermore, the laser receiving plate 8 is positioned at the projection position of the control point 3 to be measured along the direction of gravity onto the measuring platform 2. The laser receiving plate 8 is used to receive the laser signal projected by the laser plumb bob 7. Positioning the laser receiving plate 8 at the projection position of the control point 3 along the direction of gravity ensures the vertical correspondence of the laser signal transmission and reduces vertical positioning deviation. Since the laser receiving plate 8 and the control point 3 are on the same vertical line, the laser emitted by the laser plumb bob 7 can be directly projected onto the corresponding position on the receiving plate, avoiding signal misalignment caused by positional offset. This allows the laser signal to accurately reflect the vertical coordinates of the control point 3, providing a reference for subsequent measurements by the total station 5 using the prism 6 and improving vertical positioning accuracy.

[0051] The laser receiver board 8 typically features a high-sensitivity photoelectric sensing unit that can identify the center position of the laser spot and assist in manual verification via crosshairs. Optionally, a vision-sensing receiver board or an automatic tracking receiver can also be used to further enhance the automation of signal acquisition and its anti-interference capabilities.

[0052] Furthermore, prism 6 is positioned above laser receiver plate 8 and works in conjunction with total station 5 to perform closed traverse measurements. The placement of prism 6 above laser receiver plate 8 and its cooperation with total station 5 in closed traverse measurements improves the overall measurement accuracy of the system. Closed traverse measurement is a method in engineering surveying that ensures accuracy; by forming a closed loop through multiple observations, random errors can be effectively offset. The corresponding positions of prism 6 and laser receiver plate 8 ensure that the coordinates of prism 6 observed by total station 5 are directly correlated with the vertical positioning information received by laser receiver plate 8, ensuring a complete match between the horizontal measurement reference and the vertical positioning reference, avoiding cumulative errors caused by their disconnection.

[0053] In some embodiments, a fence is provided around the edge of the measuring platform 2 to ensure the safety of the surveying personnel. The fence provides safety assurance for the surveying operation and solves the safety hazards of working at height in the foundation pit. The fence effectively prevents personnel from accidentally falling and equipment from dropping, creating a physical safety barrier. The fence can be constructed using welded steel pipes, prefabricated metal mesh, or a combined safety protection system, and is securely connected to the platform in the main structure via embedded parts or bolts, effectively preventing the risk of personnel and equipment falling and meeting the safety construction specifications for foundation pit engineering.

[0054] In some embodiments, the measuring platform 2, the capping beam 1, and the support beam 4 are integrally cast structures. This integral casting structure enhances the structural stability and load-bearing capacity of the platform, effectively extending the system's service life. The integral casting structure is formed in one step during construction, with the capping beam 1, support beam 4, and measuring platform 2 forming a continuous, integrated load-bearing system. This allows for uniform load distribution, preventing structural damage caused by localized stress concentration. Furthermore, integral casting reduces subsequent installation steps, saving labor and time costs, and avoids secondary damage to the capping beam 1 and support beam 4 during installation.

[0055] In some embodiments, the total station 5 is fixed to the ground control point via a detachable connector. This connector has a leveling adjustment structure for calibrating the horizontal level of the total station 5. This detachable connector, with its leveling adjustment structure, improves the installation flexibility of the total station 5 while ensuring the horizontal accuracy of the measurement. The leveling adjustment structure precisely calibrates the horizontal level of the total station 5, resolving instrument deviation issues caused by slight tilting of the ground control point.

[0056] The method for projecting control points in the foundation pit includes the following steps: Using a laser plumb bob 7, the control point 3 to be measured in the foundation pit is vertically projected onto the concrete measuring platform 2 that has been completed at the top. After determining the location, the laser receiving plate 8 is fixed, and a prism 6 is erected above it. The total station 5 is set up at the control point with known coordinates on the ground. The backsight is then used to measure the accurate coordinates of the prism 6 on the laser receiving plate 8 using the closed traverse surveying method, thereby completing the high-precision transfer of control points from the ground to the foundation pit.

[0057] Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and all such modifications and variations fall within the scope defined by the present invention.

Claims

1. A monitoring device for control points of a foundation pit, characterized in that, include: Crown beams (1) are installed on both sides of the foundation pit; Support beam (4), which is connected to crown beam (1) and set at the top of the foundation pit, and crown beam (1) and support beam (4) together form a measurement platform (2). The measurement platform (2) is used to arrange laser receiving plate (8) and set up prism (6) to guide and measure the control point (3) to be measured in the foundation pit. Ground control point, the ground control point is set on the ground outside the foundation pit, the ground control point is equipped with a total station (5), the total station (5) is used to locate the control point (3) to be measured in the foundation pit by means of the prism (6) and the laser receiving plate (8).

2. The foundation pit control point monitoring device according to claim 1, characterized in that, The measurement platform (2) includes a one-way slab platform and a cantilever slab platform, which have different span structures to accommodate different support beam (4) layouts.

3. The foundation pit control point monitoring device according to claim 1, characterized in that, Also includes: A laser plumb line (7) is installed at the control point (3) to be measured in the foundation pit and is used to transmit laser signals to the laser receiving board (8).

4. The foundation pit control point monitoring device according to claim 3, characterized in that, The laser receiving plate (8) is positioned at the projection position of the control point to be measured (3) on the measuring platform (2) along the direction of gravity. The laser receiving plate (8) is used to receive the laser signal projected by the laser plumb bob (7).

5. The foundation pit control point monitoring device according to claim 4, characterized in that, The prism (6) is positioned above the laser receiving plate (8) and works in conjunction with the total station (5) to perform closed traverse measurements.

6. The foundation pit control point monitoring device according to claim 1, characterized in that, The measuring platform (2) is equipped with a fence at its edge, which is used to ensure the safety of the measuring personnel.

7. The foundation pit control point monitoring device according to claim 1, characterized in that, The ground control points are also retained as verification benchmarks for calibrating the measurement results on the measurement platform (2).

8. The foundation pit control point monitoring device according to claim 1, characterized in that, The measuring platform (2) is an integral cast structure with the cap beam (1) and the support beam (4).

9. The foundation pit control point monitoring device according to claim 1, characterized in that, The total station (5) is fixed to the ground control point by a detachable connector, which has a horizontal fine-tuning structure for calibrating the levelness of the total station (5).

10. The foundation pit control point monitoring device according to claim 1, characterized in that, The connection node between the cap beam (1) and the support beam (4) is provided with reinforcing ribs, which are evenly distributed around the node.

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