A material conveying device for road and bridge construction and a flow control method

Abstract

The present application relates to the technical field of flow control, in particular to a material transportation device for road and bridge construction and a flow control method. The method divides a flow unstable period by flow change, evaluates flow irregularity by combining flow rate and pressure data, and determines a problem monitoring point. The method dynamically allocates control weights of the moment by analyzing the instability influence degree of the unstable period itself, and the distribution of the problem point and the trend of flow irregularity. Finally, the flow is controlled by weighting. The present application analyzes the influence caused by blockage and segregation in the flow unstable period of concrete, strengthens the response of the control system by adapting the control weight of each moment, improves the accuracy of the control system, ensures the stable transportation of concrete, and ensures the quality of concrete transported to the pouring point.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flow control, in particular to a material transportation device for road and bridge construction and a flow control method. BACKGROUND

[0002] In road and bridge construction, concrete is widely used in road and bridge engineering due to its good compressive strength, durability and construction convenience. Pumping transportation is one of the main ways of concrete transportation. Concrete can be directly transported to the pouring point through the pipeline using a concrete pump, which is efficient, can work continuously and reduces manual handling. In the pumping transportation process, the flow control of concrete is crucial, which will directly affect the quality of concrete, the safety of the structure and the efficiency of construction.

[0003] The existing pumping transportation installs a flow meter on the concrete conveying pipeline to monitor the flow of concrete in real time and feeds back the data to the control system. The control system automatically adjusts the operating parameters of the pumping equipment to maintain a constant flow. However, during the transportation of concrete, due to vibration, changes in flow speed and other reasons, coarse aggregate segregation may occur, i.e. the separation of coarse and fine aggregates, which will affect the uniformity and workability of the concrete. Inappropriate pumping speed or poor condition of the inner wall of the pipeline, such as wear, corrosion or the presence of residues, will cause initial blockage of concrete during pipeline transportation. These problems will reduce the flow control effect of concrete if not considered. SUMMARY

[0004] In order to solve the technical problems in the prior art, the purpose of the present application is to provide a material transportation device for road and bridge construction and a flow control method. The technical solution adopted is as follows:

[0005] The present application provides a flow control method for a material transportation device for road and bridge construction, the method comprising:

[0006] In the time sequence of the stable transportation stage, the pressure data and flow rate data at equidistant monitoring points on the transportation pipeline, and the flow data at the pump outlet are obtained;

[0007] According to the stable deviation change degree of the flow data at each time, an instability index of each time is obtained. The flow instability period before the current time is selected according to the instability index. In each flow instability period, the flow irregularity degree of each monitoring point is obtained according to the deviation fluctuation degree of the pressure data and flow rate data at each monitoring point. The problem points in each flow instability period are selected according to the flow irregularity degree.

[0008] According to the distribution density of the problem points, the flow irregularity degree of the continuous problem points, the length of the flow instability period and the instability index, a control weight of each flow instability period is obtained;

[0009] The flow control is performed based on the control weight and the flow data before the current time.

[0010] Further, the method for obtaining the instability index comprises:

[0011] For any time before the current time, the difference between the flow data of the time and the adjacent time is calculated, and the average of all the differences is taken as the numerical mutation degree of each time;

[0012] The mode of the flow data before the current time is taken as the reference flow data, and the difference between the flow data of the time and the reference flow data is taken as the flow deviation degree;

[0013] The instability index of the time is obtained in combination with the flow deviation degree and the numerical mutation degree of the time.

[0014] Further, the method for screening the flow instability period comprises:

[0015] The time with the instability index greater than a preset instability threshold is taken as an instability time, and the period composed of continuous adjacent instability times is taken as a flow instability period.

[0016] Further, the method for obtaining the flow irregularity degree comprises:

[0017] For any monitoring point, the average of the pressure data of the monitoring point in all non-flow instability periods is taken as the reference pressure value of the monitoring point, and the average of the flow rate data of the monitoring point in all non-flow instability periods is taken as the reference flow rate value of the monitoring point;

[0018] In any flow instability period, the volatility of the monitoring point is obtained in combination with the variance of all the pressure data and the variance of all the flow rate data of the monitoring point;

[0019] In the flow instability period, the deviation of the monitoring point is obtained in combination with the difference between the average of all the pressure data and the reference pressure value, and the difference between the average of all the flow rate data and the reference flow rate value;

[0020] The flow irregularity degree of the monitoring point in the flow instability period is obtained in combination with the volatility and the deviation of the monitoring point.

[0021] Further, the method for screening the problem points comprises:

[0022] In each flow instability period, the monitoring points with flow irregularity greater than the preset abnormal threshold are regarded as problem points in each flow instability period.

[0023] Further, the control weight acquisition method comprises:

[0024] For any flow instability period, according to the duration of the flow instability period and the size of the instability index, an efficiency influence index of the flow instability period is obtained;

[0025] According to the flow irregularity of the overall problem points in the flow instability period, the distribution distance between the problem points and the number of problem point distribution, a transport problem significance index of the flow instability period is obtained;

[0026] In the flow instability period, according to the linear trend degree of flow irregularity under continuous distribution of problem points and the number of continuous distribution, a problem harm index of the flow instability period is obtained;

[0027] The control weight of the flow instability period is obtained by combining the efficiency influence index, the transport problem significance index and the problem harm index of the flow instability period.

[0028] Further, the efficiency influence index acquisition method comprises:

[0029] The proportion of the total period of the flow instability period before the current time is taken as the instability duration of the flow instability period;

[0030] The average value between the mean value and the maximum value of the instability index in the flow instability period is calculated for normalization to obtain the instability significance of the flow instability period;

[0031] The efficiency influence index of the flow instability period is obtained by combining the instability duration and the instability significance of the flow instability period.

[0032] Further, the transport problem significance index acquisition method comprises:

[0033] In the flow instability period, the ratio between the total number of all problem points and the total number of monitoring points is taken as the number distribution degree of the flow instability period;

[0034] The number of interval monitoring points between every two adjacent problem points is obtained, and the mean value of all interval monitoring points is calculated for negative correlation mapping to obtain the concentrated distribution degree of the flow instability period;

[0035] The mean value of the flow irregularity of all problem points in the flow instability period is taken as the irregular fluctuation degree of the flow instability period;

[0036] By combining the irregularity, quantity distribution, and concentration of traffic flow during this unstable period, significant indicators of transportation problems during this unstable period are obtained.

[0037] Furthermore, the method for obtaining the hazard indicators of the problem includes:

[0038] During this period of unstable flow, consecutively adjacent problem points are distributed according to the flow velocity direction to form a problem point distribution sequence;

[0039] When there is only one problem point in the problem point distribution sequence, the number of problem points in the problem point distribution sequence is taken as the local hazard degree of the problem point distribution sequence;

[0040] For any problem point distribution sequence with two or more problem points, the irregularity of the flow of problem points in the problem point distribution sequence is linearly fitted to obtain the fitting error; the fitting error is negatively correlated and normalized to obtain the regularity hazard coefficient of the problem point distribution sequence; the product of the number of problem points in the problem point distribution sequence and the regularity hazard coefficient is obtained as the continuous hazard; the sum of the number of problem points in the problem point distribution sequence and the continuous hazard is obtained as the local hazard of the problem point distribution sequence.

[0041] The sum of the local hazard values ​​of all problem point distribution sequences during the unstable traffic period is normalized to obtain the problem hazard index for that unstable traffic period.

[0042] The present invention also provides a road and bridge construction material transportation device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the flow control method for a road and bridge construction material transportation device as described in any of the above claims.

[0043] The present invention has the following beneficial effects:

[0044] The application divides the unstable flow period needing to be focused on through the change analysis of the concrete transportation flow, and evaluates the flow irregularity by combining the flow velocity and pressure data, so as to analyze the influence caused by the blockage and segregation in the unstable flow period. The influence degree of the construction efficiency caused by the instability of the unstable period is quantified, and the distribution of the problem points and the trend of the flow irregularity are analyzed, the significant hazard conditions of the problems in the transportation process are represented by the problem type and degree, the control weight is dynamically allocated, and the weight of the period with more serious problems is higher. Finally, the flow control is performed by weighting, the response of the problem period is strengthened, and the flow stability and the concrete quality are ensured. The application analyzes the influence caused by the blockage and segregation in the unstable flow period of the concrete, adaptively strengthens the response of the control system by the control weight of each moment, improves the precision of the control system, ensures the stable transportation of the concrete, and ensures the quality of the concrete transported to the pouring point. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only show some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0046] Figure 1 A flow control method flow chart of a material transportation device for road and bridge construction provided by an embodiment of the present application;

[0047] Figure 2 A control weight acquisition method flow chart provided by an embodiment of the present application. DETAILED DESCRIPTION

[0048] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined application purpose, the following will combine the drawings and the preferred embodiments to specifically describe the specific implementation, structure, features and effects of the material transportation device for road and bridge construction and the flow control method according to the present application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0050] The specific scheme of the material transportation device for road and bridge construction and the flow control method provided by the present application will be specifically described below with reference to the drawings.

[0051] In the pumping transportation process of concrete, the ideal state should maintain a constant flow, which helps to ensure the uniform distribution of concrete during pouring, avoid the accumulation or void phenomenon of concrete caused by flow fluctuation, and improve the uniformity and integrity of the structure. And the stability of the flow helps to reduce the risk of blockage, avoid high pressure and equipment damage caused by blockage, ensure construction safety, and reduce the segregation phenomenon of concrete in the pipeline, maintain the uniformity and workability of the concrete, and ensure the quality of the final structure. However, in the actual transportation process, the flow fluctuation will be caused by the change of the consistency of the concrete, the adjustment of the pumping speed or other factors, so accurate flow control is needed to ensure the efficiency of concrete transportation.

[0052] Since the pumping transportation of concrete is divided into a starting stage, a stable transportation stage and a stopping stage, the starting stage is the period when the concrete pump starts to work, and the flow gradually rises from 0 to the set flow threshold. The stable transportation stage is the period of maintaining the set flow threshold transportation, and the stopping stage is the period when the concrete pump stops working, and the flow gradually decreases to zero.

[0053] In the embodiment of the present application, the fuzzy control algorithm is used for flow control in the starting stage and the stopping stage, and the fuzzy control algorithm is also selected for flow control in the first 10 minutes of the stable transportation stage. At this time, the system just comes from the starting stage, and there may be transitional fluctuations, such as pump truck parameter fine-tuning, initial flow adaptation of concrete in the pipeline, etc. Such fluctuations are not real segregation or blockage. Segregation needs to accumulate aggregate settlement, and blockage needs to accumulate concrete residue or pipeline wear. Both of them need a certain period of time. It should be noted that the fuzzy control is a technology known to those skilled in the art, and will not be described here.

[0054] After the system enters the continuous stable operation period, if the flow is unstable at this time, it is highly probable that there is a real problem, and the problem has accumulated to a certain extent, which needs to be precisely intervened. Therefore, in the embodiment of the present application, the weighted fuzzy control algorithm is used for precise flow control after 10 minutes in the stable transportation stage, to improve the degree of attention to the problem part. The time when the weighted fuzzy control starts can be adjusted by the implementer according to the specific implementation, which is not limited here.

[0055] Please refer to Figure 1 , which shows a flow control method flow chart of a road and bridge construction material transportation device provided by an embodiment of the present application. The method comprises the following steps:

[0056] S1: In the timing of the stable transportation stage, the pressure data and flow rate data at the equidistant monitoring points on the transportation pipeline, and the flow data at the pump outlet are obtained.

[0057] In the stable conveying stage of the concrete pumping transportation process, data is collected for stable condition analysis, in the embodiment of the present application, a flow meter is installed at a position 10 times the pipe diameter away from the pump outlet on the concrete conveying pipeline to monitor the flow data of the concrete in real time.

[0058] Since pumping transportation is a highly efficient concrete conveying method, it is particularly suitable for long-distance horizontal transportation, and generally, the horizontal conveying distance of pumped concrete can reach hundreds of meters or even longer. Therefore, multiple monitoring points are arranged at equal intervals on the concrete conveying pipeline, and an integrated sensor is installed at each monitoring point, including a flow rate sensor and a pressure sensor to collect flow rate data and pressure data at the monitoring point in real time.

[0059] In the embodiment of the present application, the data collection frequency is set to one per second, and each dimension data is standardized and unified in dimension to avoid dimensional influence. The data collection and processing are well-known technical means to those skilled in the art, and the implementer can control it by himself, which will not be described and limited here.

[0060] S2: According to the stable deviation change degree of the flow data at each time, obtain the instability index of each time; According to the instability index, screen the flow instability period before the current time; In each flow instability period, according to the deviation fluctuation degree of the pressure data and the flow rate data at each monitoring point, obtain the flow irregularity degree of each monitoring point; According to the flow irregularity degree, screen out the problem points in each flow instability period.

[0061] In the pumping transportation process of concrete, the unstable flow part refers to the flow fluctuation or poor stability that occurs in the pumping process, and the unstable period is crucial to flow control, because unstable conditions may cause segregation, blockage or other quality problems of concrete, affecting construction efficiency and the quality of the final structure. From the time sequence up to the current time, the flow instability period is screened out through the flow fluctuation at the time, and the subsequent influence analysis of the existing problems can be carried out for the unstable period, so that the flow control for the problem part is more accurate.

[0062] In the embodiment of the present application, the method for obtaining the instability index of each time comprises:

[0063] Firstly, for any time before the current time, the difference between the flow data of the time and the adjacent time is calculated, and the average of all differences is taken as the numerical mutation degree of each time. The flow data difference between each time and the adjacent time reflects the mutation fluctuation degree of the time, and the greater the numerical mutation degree, the higher the instability of the time.

[0064] Since the flow in the transportation needs to be maintained constant, the mode of the flow data before the current time is taken as the reference flow data to represent the current stable flow size. The difference between the flow data at the current time and the reference flow data is taken as the flow deviation, and the greater the flow deviation, the greater the difference from the stable flow, and the higher the instability.

[0065] Therefore, finally, the flow deviation and the numerical mutation degree at the current time are combined to obtain the instability index at the current time. In the embodiment of the present application, the product of the flow deviation and the numerical mutation degree is normalized to obtain the instability index at the current time. The greater the instability index, the more likely it is that the current time is in an unstable state with flow fluctuations.

[0066] It should be noted that normalization is a technical means familiar to those skilled in the art, and the selection of normalization can be linear normalization or standard normalization, and the specific normalization method is not limited herein.

[0067] Further, all unstable times can be screened out by threshold judgment to obtain the unstable period. In the embodiment of the present application, the time when the instability index is greater than a preset instability threshold is taken as the unstable time, and the period composed of consecutive adjacent unstable times is taken as the flow instability period. The preset instability threshold can be set to 0.5, and the specific value can be controlled by the implementer according to the implementation scene, which is not limited herein.

[0068] It can be understood that since the segregation or blockage of concrete in the transportation pipeline is continuous, in the embodiment of the present application, when the number of times in the flow instability period is not greater than 3, it is considered to be noise data during data acquisition, and no subsequent analysis is performed.

[0069] Since conventional concrete transportation is long-distance horizontal transportation, it is further necessary to analyze the flow rate data and pressure data of different monitoring points on the concrete conveying pipeline in the flow instability period to identify possible blockage and segregation and the position of the transportation impact caused thereby. Through the screening of problem points, it can be determined whether the blockage or segregation is in a small area, whether it can be processed in time by reducing the pumping speed and gradually increasing the pressure, or whether it is in a large area, resulting in different situations that are difficult to solve, so as to give different attention weights.

[0070] The main reason for the unstable flow period is the segregation or blockage of concrete. When concrete encounters a blockage point, the flow path is blocked, causing vortex and backflow of concrete near the blockage point. These irregular flow patterns will cause irregular fluctuations in pressure. Similarly, segregation causes uneven distribution of mortar and aggregate in concrete, with more mortar in some areas and more aggregate in some areas. This uneven distribution changes the flow characteristics of concrete, causing irregular changes in fluid resistance and irregular fluctuations in flow rate.

[0071] Therefore, preferably, in the embodiments of the present application, the method for obtaining the flow irregularity of the monitoring point through the fluctuation deviation of the pressure data and the flow rate data comprises:

[0072] For any monitoring point, the average pressure data of the monitoring point in all non-flow instability periods is taken as the reference pressure value of the monitoring point, and the average flow rate data of the monitoring point in all non-flow instability periods is taken as the reference flow rate value of the monitoring point. The time of the non-flow instability period can be taken as the stable time, and the pressure data and the flow rate data at the stable time can be taken as the standard values for subsequent deviation analysis.

[0073] Firstly, in any flow instability period, the fluctuation of the monitoring point is obtained in combination with the variance of all pressure data and the variance of all flow rate data. In the embodiments of the present application, the average of the pressure data variance and the flow rate data variance of the monitoring point in the flow instability period is normalized as the fluctuation of the monitoring point. The greater the variance, the more irregular the concrete flow at the monitoring point.

[0074] Further, in the flow instability period, the deviation of the monitoring point is obtained in combination with the difference between the average pressure data and the reference pressure value, and the difference between the average flow rate data and the reference flow rate value. In the embodiments of the present application, the difference between the average pressure data and the reference pressure value of the monitoring point in the flow instability period is taken as the pressure deviation degree, the difference between the average flow rate data and the reference flow rate value of the monitoring point in the flow instability period is taken as the flow rate deviation degree, and the sum of the pressure deviation degree and the flow rate deviation degree is taken as the deviation of the monitoring point. When the difference between the flow rate and the pressure and the reference value is large, it reflects that the possibility of flow problems at the monitoring point is higher.

[0075] Finally, the flow irregularity of the monitoring point in the flow instability period is obtained in combination with the fluctuation and the deviation of the monitoring point. In the embodiments of the present application, the product of the fluctuation and the deviation of the monitoring point is normalized to obtain the flow irregularity of the monitoring point in the flow instability period. The greater the flow irregularity, the higher the possibility of concrete segregation or blockage problem at the monitoring point in the instability period.

[0076] Therefore, the monitoring points that may have problems are screened out through the threshold value. In the embodiments of the present application, the monitoring points with the flow irregularity greater than the preset abnormal threshold value in each flow instability period are taken as the problem points in each flow instability period. The preset abnormal threshold value can be set to 0.6, and the specific value can be adjusted by the implementer, which is not limited herein.

[0077] S3: obtaining a control weight of each flow instability period according to a distribution density of the problem points and flow irregularity, a change trend of flow irregularity of the continuous problem points, and a length of the flow instability period and an instability index.

[0078] During the concrete pumping process, pipe blockage and concrete segregation are both serious problems that affect the construction progress, and the blockage can cause delays and may require manual cleaning of the pipe, which not only consumes time and effort, but also can damage the pumping equipment, and the concrete segregation can affect the quality and pumping efficiency of the concrete, and the segregation can cause the strength and durability of the concrete to decrease, affecting the safety of the engineering structure. Therefore, not only the efficiency impact caused by the unstable period itself is analyzed, but also the problem hidden danger caused by the problem points is analyzed, and a higher weight is comprehensively given to strengthen the response of the control system and pay more attention to the state change at these critical moments.

[0079] Preferably, in the embodiment of the present application, the control weight of the flow instability period is obtained by the method Figure 2 The method comprises the following steps:

[0080] S301: for any flow instability period, obtaining an efficiency impact index of the flow instability period according to a length of the flow instability period and a size of the instability index.

[0081] For the overall analysis of the flow instability period, the longer the duration of the flow instability period and the greater the instability, the greater the impact on the road and bridge construction efficiency, and the higher the degree of attention required for this period.

[0082] In the embodiment of the present application, the proportion of the flow instability period in the total period before the current time is taken as the instability duration of the flow instability period, and the higher the proportion, the longer the instability condition lasts, and the greater the impact of the fluctuation of this period.

[0083] Further, the average value between the mean value and the maximum value of the instability index in the flow instability period is calculated for normalization processing to obtain the instability significance of the flow instability period, the overall instability degree of the flow instability period is reflected by the mean value of the instability index, and the highest instability degree is reflected by the maximum value, and the greater the overall instability degree and the highest instability degree, the greater the impact of the fluctuation generated in this period.

[0084] Finally, the efficiency influence index of the flow unstable period is obtained by combining the unstable duration and the unstable prominence of the flow unstable period, and in the embodiment of the present application, the product of the unstable duration and the unstable prominence of the flow unstable period is taken as the efficiency influence index of the flow unstable period, and the greater the efficiency influence index, the higher the influence of the fluctuation of the flow unstable period itself on the construction efficiency, and the control situation of this period needs to be paid more attention to.

[0085] S302: According to the flow irregularity degree of the overall problem point on the flow unstable period, and the distribution distance between the problem points and the number of problem point distribution, the transport problem prominence index of the flow unstable period is obtained.

[0086] For the possible blockage and segregation problem points, from the problem point of view on long-distance transportation, the more and the more concentrated the problem positions are when the flow is unstable, the greater the influence on the concrete transportation is, and the higher the influence on the construction efficiency is, therefore, the distribution of the problem points and the flow irregularity degree are evaluated to assess the prominence degree of the problem part in transportation.

[0087] In the embodiment of the present application, the ratio between the total number of all problem points and the total number of monitoring points on the flow unstable period is taken as the number distribution degree of the flow unstable period, and the greater the ratio is, the larger the problem area is, and the more serious the influence is.

[0088] Further, the number of interval monitoring points between adjacent problem points of each two positions is obtained, and the fewer the interval monitoring points between adjacent problem points are, the more concentrated the two problem points are, and the mean value of all interval monitoring points is calculated for negative correlation mapping to obtain the concentrated distribution degree of the flow unstable period, and the smaller the overall interval monitoring points are, the higher the problem concentration is, and the more serious the concrete transportation problem is.

[0089] It should be noted that the negative correlation mapping is a technology known to those skilled in the art, such as using inverse proportion value or negative exponential power form, etc., which is not limited and described here.

[0090] Further, the mean value of the flow irregularity degree of all problem points on the flow unstable period is taken as the irregular fluctuation degree of the flow unstable period, and the flow irregularity degree of all problem points is integrated to reflect the prominence degree of the concrete flow irregularity, and the greater the irregular fluctuation degree is, the more irregular the concrete flow is, and the more serious the problem influence is.

[0091] Finally, the irregular fluctuation degree, the quantity distribution degree and the concentration distribution degree of the flow unstable period are combined to obtain a transport problem significant index of the flow unstable period, and in the embodiment of the present application, the product of the quantity distribution degree and the concentration distribution degree of the flow unstable period is normalized to obtain the transport problem significant index of the flow unstable period, and the greater the transport problem significant index is, the greater the influence of the monitoring point with the problem on the concrete transportation is, and the higher the attention degree is required.

[0092] S303: In the flow unstable period, a problem hazard index of the flow unstable period is obtained according to the linear trend degree of the flow irregularity under the continuous distribution of the problem point and the continuous distribution quantity.

[0093] Because the concrete can form vortex and backflow near the blockage point, the flow irregularity is caused, but in the non-blockage position, the concrete can flow smoothly. The segregation causes the uneven distribution of the mortar and the aggregate in the concrete, some areas have more mortar and some areas have more aggregate, and the uneven distribution changes the flow characteristics of the concrete and causes the flow irregularity, and when the pressure fluctuation occurs at the segregation point, the fluctuation propagates downstream along the pipeline. Because the flow of the concrete is a continuous process, the pressure change in the upstream directly affects the flow state in the downstream, and when the pressure fluctuation propagates downstream, with the increase of the distance, the friction of the pipeline and the viscosity of the concrete absorb part of the fluctuation energy, and the amplitude of the fluctuation gradually attenuates.

[0094] Therefore, compared with the blockage problem point, the continuous problem hazard caused by the segregation is higher, so the hazard of the problem point in the unstable period is quantified from the irregular linear change degree of the continuous problem point, so that when the flow is controlled, more attention is paid to the data period with higher hazard, so that the flow control can be more based on the data of this period, and the problems caused by the segregation and the blockage are processed in time.

[0095] In the embodiment of the present application, in the flow unstable period, the problem points in the continuous position are distributed according to the flow velocity direction to form a problem point distribution sequence, the problem points are arranged along the concrete flow direction in the pipeline, so that the possible problem propagation situation is analyzed, and the irregularity analysis is performed on each continuous distribution problem point as a sequence.

[0096] When there is only one problem point in the problem point distribution sequence, the number of the problem point in the problem point distribution sequence is taken as the local hazard degree of the problem point distribution sequence, and only a single problem point is most likely to be a blockage point, and the hazard is relatively small. The number of the problem point, that is, the value 1, is taken as the local hazard degree of the sequence.

[0097] For any one of more than two problem point distribution sequence, the flow irregularity degree of the problem point in the problem point distribution sequence is linearly fitted to obtain a fitting error.

[0098] The concrete flow irregularity caused by the blockage point is random, and the concrete flow irregularity caused by the segregation point is linearly attenuated along the pipeline direction, so the fitting error is analyzed for the possibility of segregation. The smaller the fitting error is, the more likely the problem point distribution sequence is caused by the concrete flow irregularity of segregation.

[0099] In the embodiment of the present application, the linear fitting can be obtained by using the least square method, and the linear fitting and the linear error are well-known technical means known to those skilled in the art, which will not be described here.

[0100] Therefore, the fitting error is negatively correlated and normalized to be the regularity hazard coefficient of the problem point distribution sequence. The smaller the fitting error is, the higher the hazard coefficient is.

[0101] The product of the number of problem points in the problem point distribution sequence and the regularity hazard coefficient is taken as the continuous hazard degree, and the continuous hazard degree is combined with the continuous degree, that is, the number of problem points in the sequence, to quantize the improvement degree of the risk assessment. Furthermore, the sum of the number of problem points in the problem point distribution sequence and the continuous hazard is taken as the local hazard degree of the problem point distribution sequence, and the trend adjustment of the irregularity of the continuous distribution is obtained to obtain the hazard assessment result of the multi-continuous problem point distribution.

[0102] Finally, the sum of the local hazard degrees of all problem point distribution sequences in the flow instability period is normalized to obtain the problem hazard index of the flow instability period, which quantizes the hazard of the overall problem point position in the flow instability period. The larger the problem hazard index is, the higher the degree of attention is.

[0103] S304: Obtain the control weight of the flow instability period by combining the efficiency influence index, the transportation problem significant index and the problem hazard index of the flow instability period.

[0104] Finally, the influence of the flow instability period itself is comprehensively considered, and the transportation influence hazard degree of the problem point is considered to represent the degree of attention at this period. In the embodiment of the present application, the product of the efficiency influence index, the transportation problem significant index and the problem hazard index of the flow instability period is normalized to obtain the control weight of the flow instability period. The larger the control weight is, the higher the weight in the weighted fuzzy control is.

[0105] S4: Perform flow control based on the control weight and flow data before the current time.

[0106] In the weighted fuzzy control of concrete pumping transportation flow, different weights are assigned to each time to highlight those time periods that have a greater impact on the pumping process, especially when there is congestion or segregation. When congestion or segregation is detected, these time periods are given greater weight, which can strengthen the response of the control system and make it more focused on the state changes at these critical times. Greater weight means that the data at these times plays a more important role in the control decision, which helps to improve the accuracy of the control system and ensure that measures can be taken quickly when problems arise to better adapt to the challenges posed by congestion or segregation, thereby improving overall pumping efficiency and quality.

[0107] In the embodiment of the present application, the sum of the control weight of each flow instability period and the preset base weight is used as the weighting value of each time in the flow instability period, and the preset base weight is used as the weighting value of each time in the non-flow instability period. The preset base weight is set to 1.

[0108] From the start time of the stable delivery stage to the current time, the weighted values of all times and the concrete flow data are used as the inputs of the fuzzy controller, and the flow control instruction for the next time is output. The instruction is sent to the concrete pump truck to execute the instruction. For example, appropriately reducing the pumping speed can reduce the shear force generated inside the concrete, which helps to maintain the uniformity of the concrete and reduce segregation. It can also reduce the pressure on the blocked part to avoid exacerbating the blockage. While reducing the speed, the pumping pressure can also be gradually increased to push the concrete through the blocked area with lower pressure, etc.

[0109] In summary, the present application analyzes the changes in concrete transportation flow, divides the flow instability period that needs to be focused on, and evaluates the flow irregularity by combining flow rate and pressure data to locate the monitoring points where problems exist, so as to analyze the impact of congestion and segregation problems in the flow instability period. By quantifying the impact of instability on construction efficiency, analyzing the distribution of problem points and the trend of flow irregularity, and characterizing the significant hazards in the transportation process by problem type and degree, the control weight is dynamically allocated, and the weight of the period with more serious problems is higher. Finally, the flow control is performed by weighting to strengthen the response of the problem period and ensure the stability of the flow and the quality of the concrete. The present application analyzes the impact of congestion and segregation in the flow instability period of concrete, adapts the control weight of each time to strengthen the response of the control system, improves the accuracy of the control system, and ensures the stable transportation of concrete while ensuring the quality of the concrete transported to the pouring point.

[0110] The application further provides a material transportation device for road and bridge construction, which comprises a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and the processor implements the steps of the flow control method of the material transportation device for road and bridge construction when executing the computer program.

[0111] It should be noted that the above-mentioned embodiment sequence is only for description, and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multi-task processing and parallel processing are also possible or can be advantageous.

[0112] Each of the embodiments in the specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment mainly explains the difference from other embodiments.

Claims

1. A flow control method for a material transport device for road and bridge construction, characterized in that, The method includes: During the stable transportation phase, pressure and velocity data at equidistant monitoring points along the transportation pipeline, as well as flow rate data at the pump outlet, are acquired. Based on the degree of stable deviation of the flow data at each time point, the instability index for each time point is obtained; the unstable flow periods before the current time point are selected based on the unstable flow index; in each unstable flow period, the flow irregularity of each monitoring point is obtained based on the degree of deviation and fluctuation of the pressure data and flow velocity data at each monitoring point; and the problem points in each unstable flow period are selected based on the flow irregularity. In each period of unstable traffic, the control weight is obtained based on the density of problem points and the irregularity of their flow, the trend of the irregularity of the flow of consecutive problem points, the duration of the unstable traffic period and the instability index. Flow control is performed based on the control weights and flow data prior to the current moment. The method for obtaining the control weights includes: For any period of unstable traffic, based on the duration of the unstable traffic period and the magnitude of the instability index, the efficiency impact index of that period of unstable traffic is obtained. Based on the degree of irregularity in the overall flow of the problem points during the period of unstable flow, as well as the distribution distance between the problem points and the number of problem points, significant indicators of transportation problems during the period of unstable flow are obtained. During this period of unstable flow, the severity index of the problem is obtained based on the linear trend of the irregularity of the flow under the continuous distribution of problem points and the number of continuous distributions. By combining efficiency impact indicators, significant indicators of transportation problems, and indicators of the severity of problems during this period of unstable traffic flow, the control weights for this period of unstable traffic flow are obtained. The methods for obtaining the hazard indicators of the aforementioned problem include: During this period of unstable flow, consecutively adjacent problem points are distributed according to the flow velocity direction to form a problem point distribution sequence; When there is only one problem point in the problem point distribution sequence, the number of problem points in the problem point distribution sequence is taken as the local hazard degree of the problem point distribution sequence; For any problem point distribution sequence with two or more problem points, the irregularity of the flow of problem points in the problem point distribution sequence is linearly fitted to obtain the fitting error; the fitting error is negatively correlated and normalized to obtain the regularity hazard coefficient of the problem point distribution sequence; the product of the number of problem points in the problem point distribution sequence and the regularity hazard coefficient is obtained as the continuous hazard; the sum of the number of problem points in the problem point distribution sequence and the continuous hazard is obtained as the local hazard of the problem point distribution sequence. The sum of the local hazard values ​​of all problem point distribution sequences during the unstable traffic period is normalized to obtain the problem hazard index for that unstable traffic period.

2. The flow control method for a road and bridge construction material transportation device according to claim 1, characterized in that, The method for obtaining the instability index includes: For any time before the current time, calculate the difference in traffic data between that time and the adjacent time, and use the average of all differences as the numerical change rate at each time. The mode of the current flow data is used as the baseline flow data; the difference between the current flow data and the baseline flow data is used as the flow deviation. By combining the flow deviation and numerical mutation at that moment, the instability index at that moment is obtained.

3. The flow control method for a road and bridge construction material transportation device according to claim 1, characterized in that, The method for filtering periods of unstable traffic includes: The moment when the unstable index exceeds the preset unstable threshold is defined as an unstable moment; the time period consisting of consecutive adjacent unstable moments is defined as a period of unstable traffic.

4. The flow control method for a road and bridge construction material transportation device according to claim 1, characterized in that, The method for obtaining the flow irregularity includes: For any given monitoring point, the average pressure data of that monitoring point during all non-unstable flow periods is taken as the baseline pressure value of that monitoring point; the average flow velocity data of that monitoring point during all non-unstable flow periods is taken as the baseline flow velocity value of that monitoring point. During any period of unstable flow, the volatility of the monitoring point is obtained by combining the variance of all pressure data and the variance of all flow velocity data at that monitoring point. During this period of unstable flow, the deviation of the monitoring point is obtained by combining the difference between the average pressure data of all pressure data at the monitoring point and the baseline pressure value, as well as the difference between the average flow velocity data of all flow velocity data and the baseline flow velocity value. By combining the volatility and deviation of the monitoring point, the flow irregularity of the monitoring point during the period of unstable flow is obtained.

5. The flow control method for a road and bridge construction material transportation device according to claim 1, characterized in that, The methods for filtering the problem points include: During each period of unstable traffic, monitoring points where the irregularity of the flow exceeds a preset abnormal threshold are designated as problem points for that period.

6. The flow control method for a road and bridge construction material transportation device according to claim 1, characterized in that, The methods for obtaining the efficiency impact indicators include: The proportion of the period of unstable traffic in the total period before the current time is taken as the instability duration of the period of unstable traffic. The average value between the mean and maximum value of the instability index during the period of unstable flow is calculated and normalized to obtain the instability significance of the period of unstable flow. By combining the duration and significance of instability during this period of unstable traffic, an efficiency impact index for this period of unstable traffic is obtained.

7. The flow control method for a road and bridge construction material transportation device according to claim 1, characterized in that, The methods for obtaining the significant indicators of the transportation problem include: During this period of unstable traffic flow, the ratio between the total number of all problem points and the total number of monitoring points is used as the quantity distribution degree for this period of unstable traffic flow. Obtain the number of interval monitoring points between any two adjacent problem points, and calculate the mean of all interval monitoring point numbers to perform a negative correlation mapping to obtain the concentration distribution of the traffic during the unstable period. The mean of the flow irregularity of all problem points during the period of unstable flow is taken as the irregularity fluctuation of that period of unstable flow. By combining the irregularity, quantity distribution, and concentration of traffic flow during this unstable period, significant indicators of transportation problems during this unstable period are obtained.

8. A material transportation device for road and bridge construction, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the flow control method for a road and bridge construction material transportation device as described in any one of claims 1 to 7.

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