Smart measurement method for construction waste components

Abstract

The present invention relates to the field of construction waste treatment. Provided is a smart measurement method for construction waste components. The method comprises the following steps: S10, acquiring the weight Wwaste and bulk volume Vwaste of construction waste; S20, dividing the construction waste into two categories, i.e. inert waste and non-inert waste, the component proportions of which are respectively Pinert and Pnon-inert; and S30, establishing a general linear equation. The beneficial effects of the present invention are as follows: a construction waste mixture conforming to a classification standard can be identified quickly and accurately at a low cost, and construction waste having low classification and recycling value is excluded, thereby reducing the time cost and mechanical cost, and improving the treatment efficiency of the construction waste.

Description

An intelligent measurement method for construction waste components Technical Field

[0001] The present invention relates to the field of construction waste treatment, and more particularly, to an intelligent measurement method for construction waste components. Background Art

[0002] Construction waste, also known as building debris, refers to building materials discarded during construction, renovation, renovation, and demolition activities. Construction waste generally accounts for 25% of municipal solid waste generation (by weight). Previous research indicates that in 2014 alone, the United States generated approximately 534 million tons of construction waste, while China generated approximately 11.3 million tons. While many components of construction waste have a far lower environmental impact than domestic and chemical waste, the sheer volume of waste generated magnifies its negative impact. Therefore, construction waste management is a significant social and environmental issue for most countries worldwide.

[0003] For the sake of environmental protection and improving resource utilization, many cities have adopted the "3R" (reduction, reuse, and recycling) construction waste management measures. For a given pile of construction waste, the disposal method mainly depends on its composition. Taking Hong Kong as an example, construction waste composed entirely of inert components (i.e. chemically stable components such as concrete, bricks, sand, cement, asphalt, etc.) can be directly transferred to public filling areas, and then these wastes will be reused for land reclamation, foundation pit backfill, sand making, etc.; for construction waste containing more than 50% (by weight) inert components, it can be transported to public sorting stations for garbage classification and then classified for treatment; for construction waste with less than 50% inert components, it can be sent directly to landfills for disposal.

[0004] However, figuring out the composition of a pile of construction waste is a relatively difficult task because it is usually composed of a variety of discarded building materials mixed in random proportions. The traditional method of manual classification and then weighing and calculating can obtain accurate composition data, but it is very time-consuming and labor-intensive. For the huge amount of construction waste, the applicability of this method is obviously insufficient. In recent years, some researchers have proposed using new technologies (such as image recognition and X-ray scanning) to analyze the composition of construction waste, but these methods can only analyze the component types of construction waste (that is, find out what materials are contained) but cannot measure the quantity of each component. Therefore, a new method and equipment are needed to achieve fast, accurate, and low-cost measurement of the composition of construction waste and the quantity of each component, thereby promoting the resource management of construction waste.

[0005] Summary of the Invention

[0006] In order to overcome the shortcomings of the existing technology, the present invention provides an intelligent measurement method for the composition of construction waste, which can quickly and accurately estimate the composition of inert waste and non-inert waste in construction waste, thereby improving the treatment efficiency of construction waste.

[0007] The technical solution adopted by the present invention to solve the technical problem is: an intelligent measurement method for the composition of construction waste, the improvement of which is that the method includes the following steps:

[0008] S10. Obtaining the weight W of construction waste 废 and the bulk volume V 废 ;

[0009] S20, divide construction waste into two categories: inert waste and non-inert waste, and their composition ratios are P 惰性 and P 非惰性 ;

[0010] S30. Establish a general linear equation and calculate the composition ratio of construction waste according to the following formula:

[0011] Among them, α is the coefficient of the equation, and β is the constant term of the equation;

[0012] In step S30, P 惰性 Preset according to actual needs, assuming P 惰性 The value of is defined as θ; the steps for obtaining α and β are as follows:

[0013] S301. Randomly sample construction waste from vehicles to obtain the net weight of the waste and calculate the accumulated volume of the waste. Sorting the waste to obtain the weight of inert waste components or non-inert waste components, and then calculate the proportion of non-inert waste components or inert waste components in the waste.

[0014] S302: Data visualization: Using the accumulated volume and weight of construction waste as the horizontal and vertical coordinates, the sampled data is visualized to determine the distribution of the total volume of data samples with an inert waste component ratio greater than θ and less than θ, and to determine whether a significant dividing line is present. If a significant dividing line is present, the next step is performed; otherwise, the process returns to step S301 and the sample size is increased.

[0015] S303: Data fitting: fitting a potential dividing line using a linear fitting method, obtaining estimated values ​​of α and β based on the fitting results, substituting the estimated values ​​of α and β into the formula in step S30 to obtain the dividing line where the quantified inert waste component ratio is greater than θ and less than θ;

[0016] S304: Apply the results. After obtaining the values ​​of α and β, the formula in step S30 can be used to measure the proportion of inert waste components in the construction waste.

[0017] Furthermore, in step S10, the weight W of the construction waste is obtained. 废 include:

[0018] Use a floor scale to weigh the construction waste transport vehicle and obtain the total weight W 总 , total weight W 总 is the weight of construction waste W 废 Tare weight W of transport vehicle 车 sum.

[0019] Furthermore, in step S10, the weight W of the construction waste is obtained. 废 include:

[0020] Use the vehicle-mounted electronic scale to obtain the weight W of the construction waste 废 The vehicle-mounted electronic scale is installed at the bottom of the vehicle's cargo box.

[0021] Furthermore, in step S10, the accumulation volume V of construction waste is obtained. 废 include:

[0022] Use distance sensors to measure the average height H of construction waste 废 and compare it with the bottom area A of the transport vehicle 斗 Multiply them to get the accumulation volume V of construction waste 废 , that is, V 废 =H 废 *A 斗 .

[0023] Furthermore, the distance sensor is installed above a specific gate or on top of a vehicle bucket.

[0024] Furthermore, in step S20, the inert waste mainly includes concrete, bricks, stones, and cement mortar, and the non-inert waste mainly includes plastic, cardboard, wood, and textiles.

[0025] Furthermore, in step S301 , 5-10 data samples with inert component ratios greater than θ and less than θ are obtained.

[0026] Furthermore, in step S303, a linear fitting method based on the least squares method is used to fit the potential dividing line.

[0027] The beneficial effects of the present invention are as follows: the present invention provides an intelligent measurement method for the composition of construction waste. Compared with the composition measurement method of manual classification and then weighing and calculation, the present invention does not require human intervention and can quickly, accurately, and inexpensively identify construction waste mixtures that meet the classification standards, exclude construction waste with low classification and recycling value, thereby saving time and machinery costs and improving the efficiency of construction waste treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a flow chart of an intelligent measurement method for construction waste components according to the present invention.

[0029] FIG2 is a schematic diagram of the detailed steps of step S30 in the present invention.

[0030] FIG3 is a schematic diagram showing the relationship between the proportion of inert components and bulk density of construction waste in the present invention.

[0031] FIG4 is a schematic diagram of visualizing data of construction waste in the present invention.

[0032] FIG5 is a schematic diagram of a scenario in which the present invention is applied to a construction waste treatment plant. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to the accompanying drawings and examples.

[0034] The following will clearly and completely describe the concept, specific structure and technical effects of the present invention in combination with the embodiments and drawings, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. In addition, all the connection / connection relationships involved in the patent do not refer to the direct connection of components, but refer to the fact that a better connection structure can be formed by adding or reducing connection accessories according to the specific implementation situation. The various technical features in the invention can be combined interactively without conflicting with each other.

[0035] Referring to Figures 1 and 2, the present invention discloses an intelligent construction waste composition measurement method. This method can quickly and accurately estimate the amount of inert components (higher recycling value) and non-inert components (lower recycling value) contained in construction waste. The principle is to use the statistical positive correlation between the component ratio of construction waste and its bulk density to estimate the composition. Specifically, in this embodiment, the intelligent construction waste composition measurement method of the present invention includes the following steps:

[0036] S10. Obtaining the weight W of construction waste 废and the bulk volume V 废 ;

[0037] In this embodiment, in step S10, the weight W of the construction waste is obtained. 废 include:

[0038] Use a floor scale to weigh the construction waste transport vehicle and obtain the total weight W 总 , total weight W 总 is the weight of construction waste W 废 Tare weight W of transport vehicle 车 The tare weight of the transport vehicle is generally known, or can be obtained by weighing it on a scale when it is empty. 总 After that, you can use W 总 -W 车 Get the weight W of construction waste 废 .

[0039] In another specific embodiment, the weight W of the construction waste is obtained. 废 Including: Using a vehicle-mounted electronic scale to obtain the weight W of construction waste 废 On-board electronic scales are installed at the bottom of the vehicle's cargo box and are used to obtain real-time information about the vehicle's load. These scales are already common in many transport vehicles, such as coal trucks at coal mines and cargo transfer trucks at docks.

[0040] Furthermore, in step S10, the accumulation volume V of construction waste is obtained. 废 Including: Using distance sensors to measure the average height H of construction waste 废 and compare it with the bottom area A of the transport vehicle 斗 Multiply them to get the accumulation volume V of construction waste 废 , that is, V 废 =H 废 *A 斗 Due to road transport regulations and vehicle design specifications, the length and width of transport vehicle cargo boxes are relatively uniform. This information can be obtained directly from the vehicle manufacturer's publicly available database or through interviews with transport vehicle drivers. In actual product design, the loading height measurement device can be attached to a distance sensor above a specific gate. The data obtained by the distance sensor can be used to deduce the height of the construction waste loaded on the transport vehicle.

[0041] Similarly, in another specific embodiment, the distance sensor is installed on the top of the vehicle bucket; by measuring and calculating the average height difference before and after loading, the average loading height of the waste is obtained.

[0042] S20, divide construction waste into two categories: inert waste and non-inert waste, and their composition ratios are P 惰性 and P 非惰性 In this embodiment, the inert waste mainly includes concrete, bricks, stones, and cement mortar, and the non-inert waste mainly includes plastic, cardboard, wood, and textiles.

[0043] Before measuring the composition of construction waste, it is first necessary to classify the composition of construction waste. Currently, there are many methods for classifying construction waste around the world. For example, the U.S. Environmental Protection Agency classifies construction waste into seven categories, including (1) concrete, (2) steel, (3) wood products, (4) gypsum wallboard and plaster, (5) bricks and clay tiles, (6) asphalt tiles, and (7) asphalt concrete. In Europe, the European Union has established a comprehensive construction waste catalog, which divides construction waste into eight categories, namely (1) concrete, (2) asphalt, (3) tiles, (4) ceramics, (5) wood, (6) glass, (7) plastics, and (8) gypsum. In other countries and regions, such as Australia or Hong Kong, construction waste is usually divided into inert construction waste and non-inert construction waste, among which inert construction waste mainly includes concrete, bricks, stones, cement mortar, etc., and non-inert construction waste mainly includes plastics, cardboard, wood boards, textiles, etc.

[0044] The present invention divides construction waste into two categories: inert and non-inert. Based on this classification, the construction waste composition measurement problem is clearly defined as: measuring how much inert components and non-inert components are contained in a pile of construction waste.

[0045] Since the true density of inert materials such as concrete and bricks is generally greater than that of non-inert materials such as plastic and wood, based on this general experience, for any two piles of construction waste of equal volume, the one with a higher inert component content is generally heavier than the one with a lower inert component content. In other words, construction waste with a higher inert component content generally has a higher bulk density (different from the true density). The bulk density is equal to the total weight of the construction waste divided by the volume occupied by its bulk state. This potential law reveals the possible statistical relationship between the constituent components of construction waste and its bulk density. Figure 3 visualizes the relationship between the proportion of inert components and bulk density of construction waste. Compared to true density, bulk density is less difficult to measure and requires less equipment. Therefore, if the statistical relationship between composition and bulk density can be scientifically confirmed and quantified, this relationship can be used to achieve rapid and low-cost measurement of construction waste composition.

[0046] To validate the theoretical reasoning presented above, a large-scale data analysis was conducted. Based on Hong Kong's construction waste management practices, a large dataset was collected, consisting of 3,200,000 truckloads of purely inert construction waste (i.e., construction waste with a near-to-100% inert component ratio) and 1,100,000 truckloads of non-inert construction waste (i.e., construction waste with a near-to-100% non-inert component ratio). The dataset provided the weight and accumulated volume of each truckload of construction waste. Based on this, the accumulated density of these 4,300,000 truckloads of construction waste was calculated, and the results were compared and analyzed. Big data analysis results show that the bulk density of 3.2 million truckloads of inert construction waste fluctuates between 0.5 and 1.8 tons per cubic meter, with the majority concentrated between 0.9 and 1.5 tons per cubic meter. Meanwhile, the bulk density of 1.1 million truckloads of non-inert construction waste varies between 0.1 and 0.9 tons per cubic meter, with a concentration between 0.2 and 0.6 tons per cubic meter. These results demonstrate that the bulk density of construction waste with a higher proportion of inert components is generally greater than that of construction waste with a lower proportion of inert components, confirming the theoretical reasoning shown in Figure 3.

[0047] S30. Establish a general linear equation and calculate the composition ratio of construction waste according to the following formula:

[0048] Among them, α is the coefficient of the equation, also known as the slope; β is the constant term of the equation, also known as the intercept;

[0049] In step S30, P 惰性 Preset according to actual needs, P 惰性 The value of is between 0 and 100. Different cities may have different values ​​for the same P due to differences in design and construction specifications. 惰性 In addition, in practical applications, it is not necessary to determine P 惰性 The corresponding value of the entire interval. In practice, P 惰性 The value is usually designed in advance according to actual needs. For example, in this embodiment, the value is set at 50% in Hong Kong. In such a scenario, it is only necessary to 惰性 The required values ​​of α and β can be obtained by sampling survey. 惰性 The value of is defined as θ; the steps for obtaining α and β are as follows:

[0050] S301. Randomly sample construction waste from vehicles to obtain the net weight of the waste and calculate the accumulated volume of the waste. Sorting the waste to obtain the weight of inert waste components or non-inert waste components, and then calculate the proportion of non-inert waste components or inert waste components in the waste.

[0051] In step S301, 5-10 data samples with inert component ratios greater than θ and less than θ are obtained;

[0052] S302: Data visualization: Using the accumulated volume and weight of construction waste as the horizontal and vertical coordinates, the sampled data is visualized to determine the distribution of the total volume of data samples with an inert waste component ratio greater than θ and less than θ, and to determine whether a significant dividing line is present. If a significant dividing line is present, the next step is performed; otherwise, the process returns to step S301 and the sample size is increased.

[0053] S303: Data fitting: fitting a potential dividing line using a linear fitting method, obtaining estimated values ​​of α and β based on the fitting results, substituting the estimated values ​​of α and β into the formula in step S30 to obtain the dividing line where the quantified inert waste component ratio is greater than θ and less than θ;

[0054] In step S303, a linear fitting method based on the least squares method is used to fit the potential dividing line;

[0055] S304: Apply the results. After obtaining the values ​​of α and β, the formula in step S30 can be used to measure the proportion of inert waste components in the construction waste.

[0056] In a specific embodiment, to further demonstrate the operating mechanism of the solution proposed in the present invention, it is assumed that the requirement for acceptable construction waste is "the proportion of inert components in construction waste is not less than 50%." Then, corresponding data is collected to solve the values ​​of coefficients α and β, thereby establishing a solution for determining whether the proportion of inert components in construction waste is not less than 50%.

[0057] (1) Collecting real data: Data from 310 truckloads of construction waste with an inert component ratio of less than 50%, and data from 294 truckloads of construction waste with an inert component ratio of more than 50%.

[0058] (2) Data visualization. The data of 604 truckloads of construction waste are visualized with the accumulated volume as the horizontal axis and the weight as the vertical axis, as shown in Figure 4. It can be observed that the data points of construction waste with an inert component greater than 50% are mainly located in the upper left area of ​​the two-dimensional graph, while the data points of construction waste with an inert component less than 50% are mainly located in the lower left area of ​​the two-dimensional graph. In addition, a potential dividing line can be observed between the data points with an inert component greater than 50% and those with an inert component less than 50%.

[0059] (3) Data fitting: A linear fitting method based on the least squares method was used to fit the potential dividing line between the data points where the proportion of inert components was greater than or less than 50%, and the equation for the optimal dividing line was: W-0.42W-0.29=0.

[0060] (4) This equation is used to determine whether the proportion of inert components in construction waste is high or low. Specifically, when the result of the equation W-0.42W-0.29 is greater than 0, it indicates that the proportion of inert components in the construction waste is greater than 50%; when the result of the equation W-0.42W-0.29 is less than 0, it indicates that the proportion of inert components in the construction waste is less than 50%.

[0061] (5) Result evaluation. Based on the fitted equation W-0.42W-0.29=0, we predicted whether the proportion of inert components in the 604 trucks of construction waste collected was greater than 50%. The model's judgment results were compared with the actual data and the judgment accuracy of the model was 90.2%. This value shows that the model has good prediction performance. Therefore, the model can be encapsulated and combined with appropriate hardware equipment to form a complete intelligent measurement solution for construction waste composition.

[0062] By using the above method, the values ​​of coefficients α and β under other inert component ratio requirements (such as 30% or 60%) can also be solved, thereby obtaining a solution suitable for the new requirements.

[0063] For further explanation, Figure 5 shows the scenario of applying this solution to a construction waste treatment plant. Assume that a construction waste treatment plant only accepts construction waste with an inert component ratio greater than 50%. Anything less than 50% will be rejected. The operational process of the entire measurement solution includes the following main steps:

[0064] (1) Use distance sensors to measure and calculate the average height H of construction waste loaded on the transport vehicle.

[0065] (2) Use a floor scale to measure the total weight of the transport vehicle (including the vehicle’s own weight and the net weight of the construction waste).

[0066] (3) Multiply the average height of the construction waste obtained by the pre-registered bottom area of ​​the transport truck (length × width) to calculate the accumulated volume of the construction waste.

[0067] (4) Subtract the total weight of the transport vehicle obtained by weighing from the pre-registered deadweight of the transport vehicle to obtain the net weight of the construction waste.

[0068] (5) The net weight and bulk volume are input into a computer that encapsulates the function W-0.42W-0.29, and the result is automatically calculated and judged whether the result is greater than 0.

[0069] (6) Determine whether the measured construction waste meets the requirements based on the judgment results. If it meets the requirements, it will be accepted; if it does not meet the requirements, it will be rejected.

[0070] In summary, the intelligent construction waste composition measurement method provided by this invention, compared to methods that rely on manual sorting and then weighing, requires no human intervention and can be automatically measured using robotic equipment. This process is time-efficient and cost-effective. Compared to previous composition measurement methods based on images or X-ray scanning, this invention offers the advantage of obtaining more accurate quantities (i.e., weights) of different components.

[0071] The present invention also offers the following advantages: First, using this intelligent measurement solution, construction waste treatment plants can quickly, accurately, and cost-effectively identify construction waste mixtures that meet classification standards, eliminating construction waste with low recycling value, thereby saving time and machinery costs and improving construction waste treatment efficiency. Second, construction contractors and construction waste transport drivers can use this solution to measure the composition ratio of each truckload of construction waste delivered from the construction site and, based on the measurement results, determine whether the composition ratio needs to be adjusted, thereby determining the optimal construction waste disposal plan. Third, it can improve the social efficiency of construction waste treatment, thereby better protecting the natural environment.

[0072] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An intelligent measurement method for construction waste components, characterized in that: The method comprises the following steps: S10. Obtaining the weight W of construction waste 废 and the accumulation volume V 废 ; S20, divide construction waste into two categories: inert waste and non-inert waste, and their composition ratios are P 惰性 and P 非惰性 ; S30. Establish a general linear equation and calculate the composition ratio of construction waste according to the following formula: Among them, α is the coefficient of the equation, and β is the constant term of the equation; In step S30, P 惰性 Preset according to actual needs and set P 惰性 The value of is θ; the steps to obtain α and β are as follows: S301, sampling survey, randomly sampling construction waste on vehicles, obtaining the net weight of the construction waste, and calculating the accumulated volume of the construction waste; sorting the construction waste, obtaining the weight of inert waste components or non-inert waste components contained therein, and then calculating the proportion of non-inert waste components or inert waste components in the construction waste; S302, data visualization, using the accumulated volume and weight of construction waste as the horizontal and vertical coordinates, respectively, to visualize the sampled data, so as to determine the total amount and volume distribution of the data samples with the inert waste component ratio greater than θ and less than θ, and to determine whether there is a significant dividing line. If there is a significant dividing line, proceed to the next step, otherwise return to step S301 and continue to increase the sample size; S303, data fitting, fitting out a potential dividing line by linear fitting, obtaining estimated values ​​of α and β by the fitting result, substituting the estimated values ​​of α and β into the formula in step S30, and obtaining a dividing line where the quantitative inert waste component ratio is greater than θ and less than θ; S304: Application of the results: After obtaining the values ​​of α and β, the formula in step S30 can be used to measure the proportion of inert waste components in the construction waste.

2. The intelligent measurement method of construction waste composition according to claim 1, characterized in that: In step S10, the weight W of the construction waste is obtained. 废 include: Use a floor scale to weigh the construction waste transport vehicle and obtain the total weight W 总 , total weight W 总 is the weight of construction waste W 废 The tare weight W of the transport vehicle 车 sum.

3. The intelligent measurement method of construction waste composition according to claim 1, characterized in that: In step S10, the weight W of the construction waste is obtained. 废 include: Use a vehicle-mounted electronic scale to obtain the weight W of construction waste 废 The vehicle-mounted electronic scale is installed at the bottom of the vehicle's cargo box.

4. The intelligent measurement method for construction waste components according to claim 2 is characterized in that: In step S10, the accumulation volume V of construction waste is obtained. 废 include: The average height H of construction waste is measured using distance sensors 废 and compare it with the bottom area A of the transport vehicle 斗 Multiply them to get the accumulation volume V of construction waste 废 , that is, V 废 =H 废 *A 斗 .

5. The intelligent measurement method of construction waste composition according to claim 4 is characterized in that: The distance sensor is installed above a specific gate or on the top of a vehicle bucket.

6. The intelligent measurement method for construction waste components according to claim 1 is characterized in that: In step S20, the inert waste mainly includes concrete, bricks, stones, and cement mortar, and the non-inert waste mainly includes plastic, cardboard, wood, and textiles.

7. The intelligent measurement method for construction waste components according to claim 1 is characterized in that: In step S301, 5-10 data samples with inert component ratios greater than θ and less than θ are obtained.

8. The intelligent measurement method for construction waste components according to claim 1 is characterized in that: In step S303, a linear fitting method based on the least squares method is used to fit the potential dividing line.

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