Construct the Deflection Correction via Falling Weight Deflectometer at National Freeway

• Main Authors: Bo-Ruei Chen, 陳柏瑞
• Other Authors: Wei-Hsing Huang
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/vta7tk

碩士 === 國立中央大學 === 土木工程研究所 === 96 === Falling weight deflectometer (FWD) is the most effective and well-developed nondestructive testing equipment and has been used to evaluate the structural capacity and calculate the remaining life of pavements. With Dynatest 8000 FWD of Taiwan Area National Freeway Bureau (MOTC), this study draws a set of field operation guideline, local pavement deflection correction model, and backcalculation procedures appliable to freeways in Taiwan based on the result of field testing. This study constructed a standard test field, including test sections representing Freeway No. 1, No. 3, No. 6, drainage, and stone mastic asphalt (SMA) pavements. Standard FDW operation procedures were developed based local testing experiences, with reference to the LTPP and ASTM standard procedures. Then, the study evaluated several pavement temperature prediction models, and pavement deflection correction model for applicability in Taiwan’s freeway, and found it necessary to develop localized pavement deflection correction model. This study collected 3,302 temperature gradient data during 2007/06 to 2008/06, and 727 deflection statistics from 2007/12 to 2008/3 for analysis. A new temperature prediction model is proposed to accurately predict the effective temperature of pavements. From testing results on freeway, it is found that the deflection correction model based on deflection theory and statistics is fairly applicable to Taiwan. The results of this study provide a useful meansof evaluating pavement structures and can be used in the decision-making of pavement maintenance for National Freeway Bureau.