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Depending on the retroreflective distribution measuring device, three sets of controlled experiments were designed. To obtain the retroreflective distribution of road traffic markings, the coefficient of retroreflected luminance (RL) changes of road traffic markings under different measurement geometry was analyzed. Several observation angles commonly used in retroreflection measurements were selected. The deviation range of vertical entrance angles was set to 8°. The horizontal entrance angles were selected according to the horizontal measurement angle of a mobile retroreflectometer unit. A white road traffic marking sample, which measured 10 mm × 46 mm, was used in the experiments. The results showed that the retroreflective distribution of road traffic markings was not uniform, the influence of the change of observation angle on the RL was greater than the entrance angle, and the change of retroreflection in the direction of the vertical entrance angle was more obvious than the horizontal entrance angle.

Retroreflective traffic markings are frequently used on roadways to provide guidance to drivers as supplements to regular markings. Portable retroreflectometers are widely used to measure the photometric characteristic of retroreflective traffic markings at present. Portable retroreflectometers include an internal light source and photoreceptors. It is based on the substitution method. Substitution relies on the use of calibrated reference plate. The traffic marking has a low coefficient of retroreflected luminance. It is difficult to measure the coefficient by direct measurement method. The direct measurement method cannot assign measurement values to the reference plates. The paper proposes a new measurement method to solve the problem of measuring the photometric characteristic of the retroreflective traffic marking. It is called the expanded direct luminous intensity method, and it is different from the four methods in JT/T 690 Test Method for Photometric Characteristics of Retroreflectors. The expanded direct luminous intensity method based on CIE angular reference system. A calibrated standard source A illuminates the specimen at a distance of 15 m from the specimen. And a calibrated low-light illuminometer is used to measure the retroreflectivity of the specimen. The paper built a standard system according to this method. The measurement uncertainty of the system is 3.1% while k is 2. After comparing with several different kinds of portable retroreflectometers, the results were satisfactory. Studies have shown that this method and standard system can not only calibrate the reference plates, but also measure the photometric characteristic of retroreflective traffic markings specimens.

In filling engineering, the mechanical properties of geomaterials are the most important mechanical indicators. With the improvement of the measurement technology, the falling ball test (FBT) method has been gradually popularized and applied to the testing of geomaterials mechanical properties. In order to verify the testing accuracy of the FBT method, experimental results of the deformation modulus tested for the homogeneous fine-grained materials and the layered structures using the FBT method are compared with the K 30 plate load test, which is the earliest and the most widely used in-situ test method. And some conclusions are drawn in this present paper.

Through theoretical research and actual road condition analysis, this paper establishes the simulation calculation model and the spectrum analysis model. Through the spectrum inversion, the stable road surface state is obtained, and the conversion relationship between the reconstruction depth of the spectral reproduction method and the structural depth of the volume displacement method is obtained. Through the conversion relationship of a typical single spectrum, the relationship between SMTD and TD is obtained under each type of standard waveform. Actually, in the process of sand paving, due to the presence of the exposed part, the SMTD and TD in the actual road surface are not positively correlated, thereby correcting the relationship between SMTD and TD. The acquired road surface data is modeled by MATLAB, and the analog waveform is made according to the actual waveform, and the reduced order decomposition is performed to determine the range of a. The intercept b value is determined by comparing the experimental spectra before and after sanding. This paper solves the problem that the detection mechanism needs to perform statistical correlation test in accordance with the requirements of JTG-E60 regulations to meet the requirements of pavement assessment.

The collision between droplet and the substrate is the key of the biochip's micro-lens generated on needing positions. The numerical model was established to simulate the collision and the deformation of the droplet and the substrate.

Surface evenness affects vehicle safety, service life, and passenger comfort. The road surface with poor flatness will produce resistance to the vehicle driving, making the vehicle vibrate and bump, hindering the safety of the vehicle driving, and will also cause local water accumulation, speed up the road damage and so on. In order to make the vehicle safe, passengers feel comfortable, road life growth, road flatness detection is particularly important.In order to make the vehicle safe to travel, passengers feel comfortable, the road service life growth, and the detection of road surface evenness is particularly important. In order to overcome the shortcomings of the existing algorithms for pavement evenness, this paper has put forward a new fast algorithm that can be applied to the continuous vialog, and according to the elevation value obtains the evenness standard deviation σ. The results show that the algorithm is high reliability, which provides a reference for the upgrade of instruments and equipment, and makes up for the shortcomings that the continuous vialog cannot be tested quickly.