A test instrument for transverse drainage capacity of large-void pavement

Abstract

This utility model discloses a transverse drainage capacity tester for large-void pavement, comprising an instrument body and a water receiving tank. An inlet is located on one side of the instrument body, from which water flows into the instrument body. A limiter is provided on the instrument body, with a gap between the inlet and the limiter. An outlet is located on the side of the instrument body furthest from the inlet, and the water receiving tank is located below the outlet. The height of the instrument body's sidewall is greater than the height of the rutted surface. The position of the limiter is adjustable vertically. The gap between the inlet and the limiter is called the water collection area. Overflow outlets are located on both sides of the instrument body's sidewalls on the water collection area to allow excess water to flow out. The area between the outlet and the limiter is called the test area, where the rutted surface specimen is located. The rutted surface specimen is placed close to the limiter, with both sides of the specimen pressed against the instrument body's sidewall. Waterproof adhesive is applied to the gap between the rutted surface, the limiter, and the sidewall, ensuring that water flows only through the specimen to the outlet.

Description

Technical Field

[0001] This utility model relates to the field of road engineering testing technology, specifically to a transverse drainage capacity tester for large-void pavement. Background Technology

[0002] In the field of road engineering, the drainage performance of a pavement is one of the key indicators for measuring its quality and service life. Large-void asphalt mixture pavements, with their unique pore structure, excel in reducing road surface water accumulation and improving driving safety, and are therefore widely used in various transportation infrastructures such as highways and urban roads. However, there are currently no industry standards specifying how to accurately and efficiently assess their lateral drainage capacity. Therefore, this invention proposes a method for accurately and efficiently evaluating the lateral drainage capacity of drainage pavements.

[0003] In areas with frequent rainfall or during sudden liquid leaks, if the road's transverse drainage system fails to function effectively, rainwater and various liquids will quickly accumulate on the road surface. Influenced by the terrain, these liquids accumulate in low-lying areas, forming puddles and potholes of varying sizes and uneven distribution. Some puddles may only occupy a small portion of the road surface, appearing scattered; while others may merge into larger areas, severely impacting normal road use. This type of water accumulation causes numerous inconveniences for vehicles. When a vehicle drives over a puddle, the tires sink instantly into the water, the vehicle's center of gravity shifts, and the vehicle sways. The driver must then urgently adjust the steering wheel to maintain stability, which not only increases the difficulty of driving but also easily causes driver anxiety. Simultaneously, the high splashes of water can soil the clothing of surrounding vehicles and pedestrians, and may even obstruct the vision of drivers behind, increasing the probability of rear-end collisions and other traffic accidents. More importantly, water accumulation poses a serious threat to driving safety. On slippery roads, vehicle traction is significantly reduced. On dry roads, tires generate sufficient friction with the ground to ensure stable vehicle operation. However, the film of water formed by accumulated water acts like a lubricant, reducing the contact area and friction between the tires and the ground. When braking, insufficient grip significantly increases braking distance. A distance that would be easily stopped on a dry road can require several times that on a wet road. This means that in emergency situations, drivers may not be able to brake in time, potentially leading to collisions with vehicles, pedestrians, or obstacles, resulting in serious traffic accidents. Prolonged water accumulation also causes continuous erosion of road surface materials. Although road materials are laid and treated, tiny gaps still exist. With prolonged water accumulation, moisture seeps into the road surface material through these gaps, where chemical substances react with the material, gradually eroding its internal structure. Like water dripping on a stone, over time, the strength and stability of the road surface material decrease, and previously smooth and solid roads may develop cracks, potholes, and other defects, affecting road smoothness and comfort. In cold regions, the hazards of water accumulation are even more pronounced. When temperatures drop below freezing, water on the road surface quickly freezes into ice. Ice not only makes roads more slippery, but also causes freeze-thaw cycles on road materials. During the day, as temperatures rise, the ice melts, and moisture seeps into the road materials; at night, as temperatures drop, the moisture refreezes. This repeated freeze-thaw process damages the internal structure of the road materials, creating more cracks and voids, accelerating road damage and aging, and causing road surfaces that could have lasted for many years to develop serious defects prematurely due to freeze-thaw cycles, thus increasing road maintenance costs.

[0004] The commonly used laboratory measurement device for the transverse permeability coefficient is based on Darcy's law, using either the constant head method or the variable head method to measure the permeability coefficient of the specimen. In existing constant head testing methods, the left end of the constant head instrument is the water input point. The left opening of the container is to maintain the water head height. The asphalt mixture rutted slab specimen is sealed from top to bottom and front to back. Water is then input into the rutted slab specimen from the left side, and the water flows through the specimen to the water receiving instrument on the right. The water level in the receiving instrument is set before the experiment to maintain a constant water head height with the input water flow. A pressure tube is used to measure the water pressure in the input and output water tanks. The transverse permeability coefficient of the asphalt mixture rutted slab specimen is determined by measuring the water collected over a fixed period. However, this constant head instrument has limitations: maintaining the water head difference between the open containers on both sides is difficult, it cannot simulate the cross slope of a road, and it cannot simulate the road drainage conditions under real road surface conditions; the instrument also has many modules, resulting in poor portability. To meet the experimental requirements of Darcy's Law, this constant head instrument needs to be kept sealed. However, the rut plate specimen is large and all six sides of the rut plate need to be sealed, which makes the operation time long, difficult, and the sealing quality unstable, resulting in low testing efficiency (Research on key technologies of a transverse drainage capacity tester for large void pavement + double-layer drainage noise reduction asphalt pavement_Tang Guoqi).

[0005] Scholars have developed a device to measure the lateral drainage capacity of a pavement by assessing the water level in a large-pore pavement under a given rainfall intensity (A Transverse Drainage Capacity Test Instrument for Large-Porosity Pavements + Research on Seepage Behavior of Large-Scale Drainage Asphalt Pavement Based on Macroscopic Rainfall Tests_Luo Chaoyang). The core design idea of ​​this device is to evaluate the lateral drainage capacity of large-pore pavements by constructing a test system that simulates a real rainfall environment. Specifically, it utilizes an advanced sprinkler system to accurately simulate a certain rainfall intensity. This sprinkler system is equipped with a high-precision flow control device and uniformly distributed nozzles, ensuring a stable and uniform rainfall simulation environment within the test area, thus reproducing the water impact on the pavement as closely as possible during actual rainfall. Simultaneously, a full-size pavement model is used for rainfall tests. This pavement model not only matches the actual pavement height in size but also simulates the real pavement as closely as possible in terms of material composition and structural construction, minimizing test errors caused by model differences. Multiple high-precision pressure pipes are pre-embedded inside the pavement model, distributed at different locations and depths, for real-time and accurate observation of changes in the water level inside the pavement. By monitoring the water level data fed back by these pressure pipes in real time, a comprehensive and detailed understanding of the dynamic changes in water level inside the road surface under different rainfall intensities and drainage times can be obtained. However, this device has many limitations in practical applications. On the one hand, it requires the pre-laying of experimental roads or the use of multiple rutted slabs cast in the laboratory for testing. This process not only requires a lot of preliminary work, including site preparation, material procurement and transportation, and road surface model casting and curing, but also takes a long time. From site leveling to the road surface model being fully ready for testing, it often takes several weeks or even months. On the other hand, the construction process and quality requirements during the laying of experimental roads or casting of rutted slabs are extremely high. Any slight deviation may affect the accuracy of the test results, increasing the difficulty and uncertainty of the test. In addition, because this device requires a large-scale site and complex equipment, its construction and maintenance costs are high, resulting in high testing costs. These factors combined make this device unsuitable for widespread promotion in the testing field and difficult to meet the actual needs of large-scale engineering testing and rapid assessment of the lateral drainage capacity of the road surface. Utility Model Content

[0006] The purpose of this invention is to solve the problem of measuring the lateral drainage capacity of large-void asphalt mixtures in the laboratory. This invention can reflect the lateral drainage capacity of large-void asphalt pavements under real road conditions.

[0007] This utility model is achieved through at least one of the following technical solutions.

[0008] A transverse drainage capacity tester for large void pavement includes an instrument body and a water receiving tank. The instrument body has an inlet on one side, from which water flows into the instrument body. The instrument body is equipped with a limiter, and there is a gap between the inlet and the limiter. The instrument body has an outlet on the side away from the inlet, so that water can flow out of the instrument body. The water receiving tank is located below the outlet.

[0009] Furthermore, the height of the instrument's main body sidewall is greater than the height of the rut plate.

[0010] Furthermore, the lower part of the instrument body is equipped with height-adjustable feet.

[0011] Furthermore, the position of the limiter can be adjusted up and down to simulate different rainfall intensities.

[0012] Furthermore, the limiter is a crossbeam.

[0013] Furthermore, the distance between the water inlet and the limiter is greater than 10cm.

[0014] Furthermore, there is a gap between the water inlet and the limiter, called the water collection area. The instrument body sidewalls on both sides of the water collection area have overflow ports for excess water in the water collection area to flow out.

[0015] Furthermore, the overflow port is located below the limiter.

[0016] Furthermore, the area between the outlet and the limiter is called the test area. The rut plate specimen is located in the test area, placed close to the limiter, with both sides of the rut plate specimen pressed against the side wall of the instrument body.

[0017] Furthermore, waterproof adhesive was applied to the gaps between the rut plate and the limiter and side wall, so that water flowed only through the test piece to the outlet.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] This utility model of a transverse drainage capacity tester for large-pore pavement measures the transverse drainage capacity of a large-pore pavement by measuring the volume of water flowing through the specimen per unit time. It is used to simulate the actual transverse drainage conditions of large-pore pavement. The tester consists of two parts: the main body and the water tank. The main body has two legs at the bottom, which can adjust the cross slope of the pavement. At the front of the tester (right side of the image), there is a funnel called the inlet, through which water flows and collects before entering the next part. Within the main body, there is a crossbeam called a limiter. The area between the inlet and the limiter is called the water collection area. On both sides of the water collection area, there are overflow outlets on the instrument's side walls to allow excess water to flow out, maintaining a corresponding water head height. The limiter is adjustable up and down to simulate different rainfall intensities, improving test efficiency. At the end of the tester, there is an outlet on the instrument's side wall for water to flow out of the instrument. The area between the outlet and the limiter is called the test area. During the test, the rut plate specimen is placed close to the limiter, with both sides of the specimen pressed against the side walls of the instrument body. Water flows out of the outlet and into the water receiving tank, which has a volume scale. This design reduces the instrument's airtightness requirements and the area that needs to be sealed, improves test efficiency, and reduces test difficulty; it can simulate the actual road cross slope; and the instrument has fewer modules, making it easy to organize and carry. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a transverse drainage capacity tester for large-void pavement, as shown in the embodiment.

[0021] Figure 2 This is a side view of a transverse drainage capacity testing instrument for large-void pavement, as shown in the embodiment.

[0022] Figure 3 This is a schematic diagram of a transverse drainage capacity testing instrument for large-void pavement, as an example.

[0023] In the diagram, 1-main body of the instrument, 2-water tank, 3-foot support, 4-water inlet, 5-limiter. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] like Figures 1-3As shown in the figure, this embodiment of a transverse drainage capacity tester for large void pavement includes an instrument body 1 and a water receiving tank 2. The instrument body 1 is a square box with a side wall height greater than the height of the rut plate. The lower two sides of the square box are provided with height-adjustable foot supports 3, which can adjust the cross slope of the pavement.

[0026] The main instrument 1 is a square box with its inner wall higher than the height of the rut plate and its width equal to or slightly greater than the width of the rut plate. The rut plate can be placed tightly into the square box of the main instrument 1 along with the limiter.

[0027] The instrument body 1 has a water inlet 4 on one side, and water flows into the instrument body 1 from the water inlet 4.

[0028] In one embodiment, the inlet 4 is a funnel. The height of the instrument body's side wall is 5cm greater than the height of the rut board, and the width is 300mm greater than the width of the rut board.

[0029] The instrument body 1 is equipped with a limiter 5. A gap exists between the water inlet 4 and the limiter 5, forming a water collection area. Overflow outlets are located on the side walls of the instrument body 1 on both sides of the water collection area to allow excess water to drain out, maintaining a corresponding water head height. The position of the limiter 5 is adjustable up and down to simulate different rainfall intensities. In one embodiment, the gap between the water inlet 4 and the limiter 5 is greater than 10cm, and the limiter 5 is a crossbeam. The overflow outlets are located below the limiter 5, on both sides of the instrument body 1, with an overflow outlet notch height of 30mm.

[0030] The instrument body 1 has an outlet on the side away from the inlet 4. The water intake at the inlet 4 must be sufficient to allow water to overflow from the overflow outlet so that water can flow out of the instrument. The water receiving tank 2 is located below the outlet. The area between the outlet and the limiter 5 is called the test area. During the test, the rut plate specimen is placed close to the limiter 5, with both sides of the rut plate specimen pressed against the side walls of the instrument body 1. Water flows out of the outlet and into the water receiving tank 2. The water receiving tank 2 has volume markings. The outlet is 100 mm wide and its height is the same as the height of the square box of the instrument body 1.

[0031] This utility model discloses a transverse drainage capacity tester for large-pore pavement, which measures the transverse drainage capacity of large-pore pavement by measuring the volume of water flowing through the specimen per unit time. The experimental steps include:

[0032] 1) Place the main body 1 of the instrument on a horizontal surface and add pads under the foot support 3 so that the instrument as a whole reaches the cross slope of the target road surface.

[0033] 2) Place a rut board in the test area, with one side of the rut board close to the limiter 5 and both sides of the rut board close to the side wall of the instrument body 1.

[0034] 3) Apply waterproof adhesive to the gap between the rut plate and the limiter 5 and the side wall so that the water flows only through the test piece to the outlet.

[0035] 4) A continuous water source is injected into the inlet. After the water enters the water collection area, it flows out from the outlet. The water intake of inlet 4 should be such that water flows out from the overflow outlet.

[0036] 5) After the water flow velocity, flow rate, and other parameters of the water flowing out of the outlet remain relatively constant and without significant fluctuations for a certain period of time, collect the water flowing out of the outlet using water collection tank 2, and start timing simultaneously to record the volume of water flowing out of the outlet over a period of time. The volume of water flowing through the specimen per unit time is the indicator for measuring the lateral drainage capacity of the large-pore pavement.

[0037] To ensure the accuracy and reliability of the test results, the water flowing out of water tank 2 needs to be collected three times, and the volume of water collected each time and the time should be recorded. The average volume of water flowing through the specimen per unit time in the three tests is taken as the index to measure the lateral drainage capacity of the large-pore pavement.

[0038] This invention provides a transverse drainage capacity testing instrument for large-void pavements, which solves the problems of current transverse drainage capacity testing methods that cannot accurately reproduce the actual transverse drainage state of pavements and require high instrument sealing and extensive preparation. The design fully considers the complexity and diversity of actual pavement drainage environments, achieving accurate and efficient testing of the transverse drainage capacity of large-void pavements. Regarding the accurate reproduction of the actual transverse drainage state of pavements...

[0039] In terms of reducing preparation work, the device of this invention features a compact and modular design, with simple connections between components, facilitating assembly and disassembly. Before testing, simply place the rutted slab specimen in the designated position on the transverse drainage capacity testing instrument for large-void pavements, and the installation and debugging of the device can be completed through simple operations, greatly shortening the test preparation time. Furthermore, the device of this invention is highly portable, facilitating rapid transfer and installation between different sites, and can meet the needs of different engineering sites for testing the transverse drainage capacity of pavements. The device of this invention has significant advantages in testing the transverse drainage capacity of large-void pavements, effectively solving the problems existing in current testing devices, and providing a more advanced and practical technical means for the quality inspection and performance evaluation of pavement engineering.

[0040] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, enabling those skilled in the art to better understand and utilize it.

Claims

1. A large void pavement transverse drainage capacity tester characterized by, The instrument includes a main body (1) and a water tank (2). The main body (1) has a water inlet (4) on one side, and water flows into the main body (1) from the water inlet (4). The main body (1) is equipped with a limiter (5), and there is a gap between the water inlet (4) and the limiter (5). The main body (1) is equipped with an outlet on the side away from the water inlet (4) so ​​that water can flow out of the main body (1). The water tank (2) is located below the outlet.

2. The transverse drainage capacity tester for large-void pavement according to claim 1, characterized in that, The height and width of the side wall of the instrument body (1) are both greater than the height of the rut plate.

3. The transverse drainage capacity tester for large-void pavement according to claim 1, characterized in that, The instrument body (1) is equipped with height-adjustable foot support (3) at the bottom.

4. The transverse drainage capacity tester for large-void pavement according to claim 1, characterized in that, The position of the limiter (5) can be adjusted up and down to simulate different rainfall intensities.

5. The apparatus for testing the transverse drainage capacity of a large-void pavement according to claim 4, wherein The limiter (5) is a crossbeam.

6. The transverse drainage capacity tester for large-void pavement according to claim 1, characterized in that, The distance between the water inlet (4) and the limiter (5) is greater than 10cm.

7. The transverse drainage capacity tester for large-void pavement according to claim 1, characterized in that, There is a gap between the inlet (4) and the limiter (5), which is called the water collection area. The instrument body (1) on both sides of the water collection area has an overflow port for excess water in the water collection area to flow out.

8. The apparatus according to claim 7, wherein The overflow port is located below the limiter (5).

9. The transverse drainage capacity tester for large void pavements of claim 1, wherein, The area between the outlet and the limiter (5) is called the test area. The rut plate specimen is located in the test area and is placed close to the limiter (5). The two sides of the rut plate specimen are close to the side wall of the instrument body (1).

10. The transverse drainage capacity tester for large-void pavement according to claim 1, characterized in that, Apply waterproof adhesive to the gap between the rut plate and the limiter (5) and the side wall so that the water flows only through the specimen to the outlet.

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