瀝青混凝土舖面整修作業之開放交通時機研究

Preliminary study for the Exact Opening time of Overlay Pavement to Traffic

許皓昇(Hau-Sheng Shiu)

指導教授 ： 張達德

中原大學/工學院/土木工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100213

摘要

近年來，交通量與載重日益增加，高速公路加舖工程之施工品質更加難以掌握。一般加舖工程施工時，為保持高速公路之服務效能，多採行夜間施工，常於滾壓完成後或僅養治1至2小時後即行開放交通。因養治時間之不足，瀝青混凝土在尚無法有效抵抗輪荷重之情況下，造成初期塑性變形，且成中、後期舖面破壞之成因。
對於結構車轍研究方面，本研究以不同瀝青膠泥之瀝青混凝土，於40℃與60℃下進行車轍輪跡試驗，評估各瀝青混凝土抗永久變形能力；而對於開放通車時機方面，以符合高公局級配，配合目前常用之中油ACI-20膠泥與改質瀝青，進行馬歇爾配合設計求得最佳含油量，據以製作AC試體進行間接張力試驗、動彈模數試驗及車轍輪跡試驗，求出不同溫度(30、40、50、60、70及80℃)下之車轍發展型態與變形量，並對其結果進行分析，以求出最適之開放交通之溫度；
再者，本研究模擬四季之季平均溫度於室內進行瀝青混凝土終壓完成後之降溫量測試驗與實際至現場舖面作降溫量測試驗，將其觀測結果與輪跡試驗之成果彙整分析，進而求得最佳開放交通時機。

本研究成果可歸納成下列結論：
1.改質瀝青對於瀝青混凝土於高溫時能提供舖面較佳之抗
車轍成效。
2.於本試驗條件下，瀝青混凝土溫度於建議開放交通溫度
之下時，其抗車轍發展機制為瀝青膠泥之黏滯度所控
制；而於溫度上升時，其抗車轍破壞機制由原瀝青膠泥
之黏滯力轉為粒料之互鎖力控制。
3.由本研究得到中油ACI-20最佳開放交通時機為50℃及改
質瀝青為60℃。
4.從瀝青膠泥之軟化點予以分析，得知最佳開放交通之溫
度約在瀝青膠泥軟化點附近，故軟化點較高之瀝青膠泥
開放交通之溫度亦高。
5.瀝青混凝土鋪面內部不同深度處其降溫速率變化不大，
但距其與表面深度愈深有明顯的溫度梯度分布。

關鍵字

開放交通時機 ； 輪跡試驗 ； 車轍 ； 加舖工程

並列摘要

In the past few years, the quality control of highway pavement maintenance becomes more difficult with increasing traffic and vehicle loading. Usually, the overlay works of pavement maintenance were pressed to perform through midnight to next morning, and often releases 1~2 hr after for maintaining the effect of highway service. Because of the insufficient time lag, the overlay asphalt concrete has not yet gained an anticipated strength to resist the wheel loads. Meanwhile, plastic deformation occurs, and causes the pavement’s long-term failure.
In the research, asphalt concrete with different asphalt is used under 40℃ and 60℃ for Wheel-tracking Test and to estimate the ability of different kind of asphalt concrete to resist permanent deformation. In the aspect of choosing the timing to admit traffic passing, with ACI-20 asphalt and the high stiffness asphalt, which now commonly used, to perform Marshal’s Mix Design to get the optimum of asphalt, and use the optimum to make AC specimen and run the indirect tension test, the Dynamic Elastic Modulus test and the Wheel-tracking Test, to determine the type of rutting and it’s magnitude under different temperature （30、40、50、60、70 and 80℃）, subsequently analyzing the result and determine the most appropriate temperature of admitting passing;
Moreover, this research simulates the average temperatures of the annual four seasons and performs the experiment of temperature descending indoors after the after-final-rolling of the asphalt concrete, and actually performs the experiment of temperature descending in situation. Analysis is done and the results are interpreted to determine the most appropriate opening time to traffic.

The results of this study can be concluded as follows:
1. Asphalt concrete with high stiffness asphalt
can provided a better performance of rut
resistance under high temperature.
2. In these series simulation tests, the
mechanism of development of the rut was
controlled by the viscosity of the asphalt
under the condition of temperature recommended
for opening to traffic, and was turned to
controlled by the interlock effect with the
temperature increased.
3. According to the results of this study, for a
newly overlaid course, the descending
temperature adequate for opening to driving
vehicle is 50℃ for ACI-20 asphalt, and 60℃
for high stiffness asphalt.
4. By analyzing the soften point of the asphalt,
the descending temperature adequate for
opening to driving is near the soften point,
and that means the higher the soften point is,
the higher the descending temperature we gets.
5. The decreasing rates of the temperature inside
the different depths were nearly the same, but
the temperature gradient would become more
evidently with the depth increasing.

並列關鍵字

rutting ； wheel tracking test ； opening time to traffic ； overlaid pavement

參考文獻

LTPP/FR-90-001, 1990.

【25】 Department of Transportation, State of California, Standard

Specifications, pp.39~23, 1988.

【26】 David Broek, “Elementary Engineering Fracture Mechanics,” Fourth

【27】 Freddy L. Robert, Prithvi S. Kandhal, E. Ray Brown, Dah-Yinn Lee,