JPH0246081B2 - KANIROMENSEIJOSOKUTEIKI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a simple road surface property measuring device that can easily and accurately measure the properties of a paved road surface.

Japan's roads have been steadily improved through past efforts, and the rate of paved roads has also improved.
Although these pavements have been fulfilling their mission well for many years, in recent years the proportion of maintenance and repair work has been increasing due to a decline in serviceability. Maintenance and repair is important not only to ensure the serviceability of pavements, but also from the viewpoints of pavement durability and economic efficiency, and it is necessary to carry out maintenance and repairs as soon as possible before pavements become extremely damaged or deteriorate. In order to perform maintenance and repair, it is necessary to properly understand the road surface condition.

As a standard for maintaining and repairing pavement, the method based on the ``Road Maintenance and Repair Guidelines'' published by the Japan Road Association is currently the most standard method used by maintenance and repair personnel. However, this method actually measures three road surface characteristics: cracking rate, rut depth, and standard deviation of longitudinal unevenness, and calculates the pavement service index (PSI) based on this.
The road surface repair method is determined based on the PSI value, and the drawback is that the survey requires a huge amount of money and requires the mobilization of personnel.

It is nearly impossible to survey the nation's roads, which total more than 1.1 million km, using this method, and there is a call for the development of a simpler measurement method.

The object of the present invention is to meet such demands and to provide a simple road surface property measuring device that can replace the road surface survey method with the above-mentioned standard method.

That is, the present invention provides a vibration meter and a recorder for recording the vibrations of the vibration meter in a vehicle that can run.
A vehicle mileage measuring device and a signal device interlocked with the mileage measuring device are provided, and a pulse signal from the signal device that is emitted every certain distance traveled by the vehicle is sent to a recorder to advance the chart of the recorder. The gist of this invention is the structure of a simple road surface condition measuring device, which is characterized by recording the maximum width of amplitude over a fixed travel distance.

The conventional standard method based on the ``maintenance and repair network'' measures the three road surface characteristics of each road lane: crack rate, amount of ruts, and amount of longitudinal unevenness, and calculates the pavement service index (PSI) using the following formula. ) are looking for.

PSI=4.53−0.518logσ−0.371C−0.174D ^2Here , PSI=Pavement serviceability index σ=Standard deviation of longitudinal unevenness (mm) C=Crack rate (%) D=Average rut depth (cm) In addition to PSI, there is also Maintenance Index (MCI) to express road surface condition. This MCI is the crack rate,
Using characteristics such as the amount of ruts and the amount of longitudinal unevenness,
It is used for comprehensive evaluation from the perspective of road administrators. This MCI is also used together with PSI.

PSI can be said to specifically evaluate road surfaces using an index that comprehensively captures road surface properties. and,
The ``Road Maintenance and Repair Network'' shows approximate construction methods as shown in Table 1.

Table-1 Serviceability Index (PSI) Approximate corresponding construction methods 3 to 2.1 Surface treatment 2 to 1.1 Overlay 1 to 0 Replacement The standard method in the "Maintenance and repair essential network" includes cracking rate, amount of rutting, amount of longitudinal unevenness etc. are measured using the following methods.

The crack rate is calculated by assuming a square grid every 0.5m in length and width on the road surface, and recording the crack condition in each square for each lane.Photographs are taken using the sketch method and a crack measuring vehicle, and the results are calculated based on the photographs. A measurement method based on the entry method is used.

The amount of ruts is the section of the route (about 1 km)
Measurements are taken for each lane at equal intervals of 50 to 100 m, taking the maximum value for each cross section as a representative section, and the amount of rutting in that section is expressed as the average value of those maximum values. There are two methods of measurement: one using a straight ruler or a water line, and the other using a rut digging wheel.

To measure longitudinal unevenness and corrugation, use a direct-reading unevenness measuring device with feet (3m ruler with feet),
or 1.5m using a 3m profilometer
It is measured in intervals. First, all measured values are divided into a certain number of groups (6 to 10 from the beginning), and the difference between the maximum and minimum values of each group, that is, the range (R), is calculated. Calculate the mean value () of the range (R) of the group. Next, the standard deviation (σ) is determined using the following formula.

σ=R/−/d ₂ where d ₂ is a constant depending on the number of measurements in the group.

Next, the simple road surface condition measuring device of the present invention will be explained according to the illustrated embodiment. The measuring machine shown in FIG. 1 shows an embodiment using one vehicle, and the measuring machine shown in FIG. 2 shows an embodiment using two vehicles. Further, FIGS. 3 and 4 show system diagrams from the distance measuring wheel to the vibration meter and its recorder in the embodiment shown in FIGS. 1 and 2, respectively.

In the figure, 1 is a self-propelled vehicle, and in the case of FIG. 1, it can be configured as a dedicated vehicle or a commonly used vehicle such as a light van can be used. In the case of Fig. 2, it is a towing vehicle. Reference numeral 2 denotes a towed vehicle, which is equipped with measuring instruments and is towed by a self-propelled vehicle 1, which is a towing vehicle. 3 is a vibration meter, which is a mechanical vibration meter having a vibrating string consisting of a weight, a spring, a damper, etc. The vibration meter 3 is a running self-propelled vehicle 1,
Alternatively, it is mounted on the towed vehicle 3. Reference numeral 4 denotes a recorder which records the amplitude of the vibration meter 3 with respect to the distance traveled, and displays it graphically or digitally. Reference numeral 5 denotes a distance measuring wheel, which is provided separately from the traveling wheels and is provided with an air cylinder or the like so that it always contacts the road surface with a constant pressure. Reference numeral 6 denotes a trip meter, which is attached to the distance measuring wheel 5 and forms a traveling distance measuring device. Reference numeral 7 is a signal device which is linked to the trip meter 6 of the distance measuring device and oscillates into a pulse signal every fixed distance traveled. The pulse signal oscillated by the signal device 7 is sent to the recorder 4, and the chart of the recorder 4 is advanced by the pulse signal. Reference numeral 8 is a cushion for supporting the vibration meter 3 and the recorder 4.

When using the simple road surface condition measuring device of the present invention, first select a plurality of routes that will serve as a reference,
The measuring device of the present invention is run on these road surfaces at a uniform speed to measure the properties of the road surface in a predetermined section. In other words, the maximum width of the amplitude over a certain travel distance within a given section is measured, and the standard deviation thereof is determined.The road surface properties in the same section of the route are also actually measured, and the standard of the amount of longitudinal unevenness in that section is determined. Determine the deviation, pavement service index, etc., and calculate the correlation between the standard deviation value obtained from the maximum width of the amplitude obtained by the measuring device of the present invention, the standard deviation value of the longitudinal unevenness amount by actual measurement, the pavement service index, etc. It is.

Next, regarding the route where the road surface condition is measured,
The measuring device of the present invention is run at a uniform speed, the maximum width of the amplitude is measured in each predetermined section of the route, the standard deviation is determined, and the standard deviation of the amount of longitudinal unevenness is determined using the correlation determined in advance. The road surface condition is evaluated by converting it into a pavement serviceability index.

When using the measuring device of the present invention, since the vibration meter 3 is mounted on the self-propelled vehicle 1 or the towed vehicle 2, if this measuring device is run at a constant speed on the route to be measured, the road surface will be measured. The vibration meter 3 can very easily sense the state of the unevenness in the area. It has the practical benefit of not requiring labor-intensive instruments such as direct-reading unevenness measuring devices and profile meters that are conventionally used for road surface measurements, and by recording the amplitude of the vibration meter 3 on the recorder 4, the measurement route section can be easily measured. This has the practical benefit of automatically recording the unevenness of the road surface.

In addition, when using the measuring device of the present invention, the vibration meter 3
The chart of the recorder 4 is advanced by the pulse signal from the signal device 7 linked to the trip meter 6 of the mileage measuring device, which is transmitted every time the self-propelled vehicle 1 or the towed vehicle 2 equipped with the vehicle travels a certain distance. Therefore, the amplitude due to road surface irregularities recorded on the chart is an accumulated record of the amplitude within a certain section traveled as shown in Figure 5, and the maximum and minimum values within that section are displayed. The amplitude range W can be easily read, and there is no need for integration as in conventional methods, making analysis of road surface conditions extremely easy and minimizing chart consumption. It has real benefits.

For this reason, by using the simple road surface condition measuring device of the present invention, surveys can be carried out efficiently by a small number of surveyors, making it possible to conduct road surface surveys over a wide area. .

[Brief explanation of drawings]

The figures show an embodiment of the present invention; FIG. 1 is a side view showing the arrangement of instruments when a self-propelled vehicle is used; FIG. 2 is a side view showing the arrangement of instruments when a towed vehicle is used. A side view showing the state; FIG. 3 is a system diagram of the embodiment shown in FIG. 1; FIG. 4 is a system diagram of the embodiment shown in FIG. 2; FIG. The front view, Figure 6 is a correlation diagram between PSI and the standard deviation calculated from the maximum width of the amplitude obtained by the measuring device of the present invention, and Figure 7 is the correlation diagram between the amount of vibration unevenness of the profile meter and the measuring device of the present invention. FIG. The symbols in the figure are explained as follows. 1 is a self-propelled vehicle, 2 is a towed vehicle, 3 is a vibration meter, 4 is a recorder, 5 is a distance measuring wheel, 6 is a trip meter, 7 is a signal device, and 8 is a cushion.

Claims (1)

[Claims] 1. A vehicle capable of running is equipped with a vibration meter, a recorder that records the amplitude of the vibration meter, a vehicle mileage measuring device, and a signal device that is linked to the mileage measuring device, This simple road surface condition measuring device is characterized in that a pulse signal from a traffic signal is sent to a recorder to advance the chart of the recorder, and the maximum width of the amplitude during a certain travel distance is recorded.