PURPOSES : For high driving performance and service life of cement concrete pavement, construction quality must be secured. The construction quality is to be measured after pavement construction, but in this case, it is difficult to improve construction quality. Therefore, it is necessary to develop a method for measuring and correcting the profile of the pavement and subbase so that the construction quality can be monitored immediately after construction. METHODS : The device that can measure the construction quality of cement concrete pavement has been developed. Through the experiment simulating the field situation, the profile of the pavement and subbase was measured and calibration method was developed. RESULTS : In the measured profile, an outlier by the sensor and noise by the sensor and vibration were measured, and a step-like profile was measured differently from the acture one. To remove outliers, the boxplot outlier removal method was applied by overlapping each data group. The noise were removed by a low pass filtering. And, it was calibrated to a profile similar to the acture one through the sampling interval adjustment and the weighted moving average method. CONCLUSIONS : The method that can measure and calibrate the profile that is almost identical to the actual one has been developed. Accordingly, it is expected that the performance of the pavement can be improved by accurately monitoring the construction quality immediately after construction.

PURPOSES : Recently, interest in maintaining aged concrete pavements has been increasing. An asphalt overlay is generally used for pavement maintenance, and a tack coat is used to secure interlayer adhesion. Particularly, aged concrete pavements are required for higher adhesion performance of tack coats for attaching interlayers to materials with different properties. Insufficient interlayer adhesion could cause pavement damage, such as slippage, rutting, shoving, corrugation, and pothole. In this study, we examined the performance of interface adhesion by applying a tack coat material developed for maintaining aged concrete pavement. METHODS : In this study, we examined the effect of adhesion performance at the pavement interface, using a tack coat material developed for the maintenance of aged concrete pavement. RESULTS : The developed tack coat not only accomplished the performance objectives but also improved the results by more than 12 to 43%, compared to commonly used materials. CONCLUSIONS : The use of developed tack coat is expected to improve the interlayer adhesion and reduce the delay of the maintenance process in aged concrete pavement.

PURPOSES : The purpose of this study was to develop the evaluation methodologies for spraying amount and sprayed condition of curing compound based on IoT technology when concrete pavements are constructed. METHODS : To measure the spraying amount of curing compound, a turbine type flowmeter was selected and a number of laboratory experiments were performed to verify the applicability of the selected sensor. To evaluate the uniformity of the sprayed curing compound on the concrete pavement surface, image process technologies were examined using pictures taken from the actual construction sites and from the test specimens. RESULTS : By performing experiments using water and curing compound, the selected flowmeter was verified to properly be applied to measure the spraying amount of curing compound with an acceptable accuracy. By conducting image processing using pictures of the sprayed curing compound on the concrete pavement surface, it was found that the 8 color analysis method was the best to evaluate the uniformity of the sprayed curing compound. CONCLUSIONS : From this study, it was concluded that the spraying amount of curing compound could be accurately measured using a turbine type flowmeter and the uniformity of the sprayed curing compound on the concrete pavement surface could be properly evaluated using an image processing technology.

PURPOSES : This study suggests an estimated texture depth (ETD) equation for concrete pavements, applicable to highway pavement texture, and the measurement method of mean profile depth (MPD) in a longitudinal texture. METHODS : First, we proposed the most suitable ETD equation through the correlation between ETD data and the measured mean texture depth (MTD) data. Second, we suggested a novel MPD measurement method, by checking the error of the ETD data and measured MTD data by the measurement method. RESULTS : The ETD equation presented by Fisco and Plati was considered the most appropriate for the transverse texture. In addition, the correlation between ETD and the measured MTD was good in the longitudinal measurement method. The ETD equation of Fisco and Plati is suitable for longitudinal texture, and the MPD measurement method obtained good results when applied to transverse measurements. To verify the novel measurement method, we confirmed the correlation between the SR and MPD data using a novel method. The correlation for the novel measurement method is 0.7. CONCLUSIONS : Accordingly, the ETD equation presented in the existing literature has a good correlation between ETD data and the measured MTD data, but it did not reflect longitudinal texture data. Therefore, we assumed the ETD equation produced in this study, and suggested the transverse measurement method in the longitudinal texture.

PURPOSES : The exposed aggregate number (EAN) and mean texture depth (MTD) of exposed aggregate concrete pavement (EACP) influence the functional performance of EACP in terms of pavement noise and skid resistance. The selection of the exposure time of EACP is important because the designed EAN and MTD of EACP can be achieved when the exposure process is performed at an appropriate time. On the one hand, too early exposure may cause protrusions and unwanted removal of aggregates and mortar. On the other hand, late exposure may cause difficulty in exposure of the mortar. In this study, a method to determine the optimum exposure time for EACP is suggested using a non-destructive method. METHODS : A set of laboratory tests was performed to investigate the variation in EAN and MTD of EACP according to the elastic modulus obtained by non-destructive equipment. From the results of this investigation, the optimum exposure time using the non-destructive method and the exposure time window (ETW) method was suggested. In addition, the usefulness of ETW suggested by laboratory tests was verified from a field application. RESULTS : From the laboratory tests, it was found that the targets of the surface condition of EACP (EAN: 59 per 25 cm2, MTD: 1.39 mm) can be achieved when the concrete elastic modulus is higher than 20GPa. The proposed guideline using the non-destructive method was applied for the field construction of EACP and achieved similar results. CONCLUSIONS : It was found that the proposed guideline for determining the exposure time window based on non-destructive testing is useful.