應用慣性式平坦儀量測數據於道路整建平坦度驗收之研究

Abstract

國內道路整建後平坦度驗收規範多採三米直規進行檢測，但其檢測效率不佳，且費時費力；本研究採用台灣大學研製之慣性式雷射平坦度檢測設備，於全國實測新建完成與大型整修前、後道路之平坦度，分析是否通過營建署訂立之市區道路平坦度驗收規範草案門檻值，與現行之三米直規驗收標準。 經電腦程式模擬三米直規量測值顯示，國內大多數新建路段可通過單點高低差驗收，但約39％路段之標準差值超過驗收門檻2.6公釐。若以重鋪道路之平坦度檢測資料代入模擬，則約有7％之路段無法通過單點高低差檢驗，但卻有高達73％之路段，其連續性三米直規檢測之標準差高於驗收門檻值。研究並顯示，新建路段平坦度值大多優於重鋪路段，若以營建署之市區道路平坦度驗收規範草案標準觀之，約七成路段可通過IRI≦350cm/km之要求；而重鋪路段之平坦度表現不甚理想，通過依道路等級差異訂立之不同要求門檻的比率僅四成。多數路段外車道較內車道有較高之IRI值，但研究發現部份新建道路內車道IRI值較外車道來得高，其原因多為該路段人（手）孔蓋設置於內車道而非外車道，故證實人（手）孔蓋對平坦度有明顯負面影響。

The smoothness specification of roadway construction is specified for using 3-meter straightedge in Taiwan. The acceptance criteria vary depending on the categories of roadway classes. Two parameters, maximum heave and dip of each measurement and standard deviation of one measured section, are used to determine the level of acceptance. For construction’s quality assurance, data are collected for every 1.5 meter interval at sample sub-sections by using the 3-meter straightedge. It is a very time consuming process for data acquisition and analysis. The objective of this research study is to develop a simulation model for analyzing the 3-meter straightedge result based on the continuous data collected from inertial profiler. Comparison of analyzed results between the current process and the simulation model is presented. In this study two types of roadway construction are evaluated. They are new pavement sections and mill/ overlay pavement sections. A total length of 89000 meter of urban street is surveyed by inertial profiler and computer software is developed for the simulation purpose. It is found that 39% of the new pavement sections and 73% of the mill/ overlay pavement sections do not meet the smoothness specification even though they were accepted by the agents utilizing the current sampling measurement method. It is concluded that the developed simulation model can provide an efficient and accurate evaluation of smoothness for pavement construction. Moreover, based on the current specification used by the Construction and Housing Bureau, about 70% of the newly constructed city roadway passes the threshold of IRI≦350 cm/ km while only 40% of the mill/ overlay city roadway meets the standard. From the analyzed data it is also found that the manholes affect the smoothness significantly.