- 學位論文
透水混凝土受落塵阻塞模擬試驗
Simulation of Clogging Effect Induced By Falling Dust on Porous Concrete
摘要
台灣土地開發面積擴張，且多採用不透水鋪面設計，因地表不透水面積過多，使土壤涵養水源功能喪失，地表逕流迅速流失。多孔隙瀝青混凝土具有保水、降溫、提升排水效果，但隨著交通量及使用年份的增加，其排水功能也會逐漸降低，而孔隙阻塞也就成了最大的問題之一。 瀝青鋪面孔隙阻塞原因可歸類為孔隙阻塞與孔隙閉合，其中阻塞物如道路砂塵、飛來的砂塵、車輛挾帶泥砂或是磨損的粒料；孔隙的閉合則較常發生於多孔隙瀝青混凝土，瀝青因車輛荷重的累積而產生移動進而漸漸填滿孔隙，或是粒料重新排列所產生的閉合，而本研究針對透水混凝土受落塵量阻塞影響進行模擬試驗，探討透水性混凝土受自然落塵量及團塊土塵降落後，再經過降雨後其孔隙阻塞情況及透水能力的變化，試驗共4組配比，配比中粒料皆為垃圾焚化爐底渣粗細粒料，水泥用量為130 kg/m3及200 kg/m3，模擬落塵自然降落並探討不同孔隙率下試體受落塵阻塞後且經由下雨將落塵帶進試體裡之影響及現地透水量的變化。 4組配比在落塵模擬試驗前，其透水量在1399.75 ml/15sec~1412.91 ml/15sec間，落塵模擬試驗使用屏東縣2011年平均每月落塵量，以10倍、20倍增加落塵量後模擬落塵自然降落以及以倍數增加落塵量模擬團塊土塵掉落於鋪面上，再經由降雨後將落塵帶入試體裡，而根據試驗結果得知，透水性混凝土因具高孔隙率特性，若排除其他阻塞因素下，自然落塵量對透水混凝土孔隙阻塞之影響甚小，而模擬團塊土塵至15倍時，雖然鋪面現地透水量有大幅下降之趨勢，但其透水量仍符合日本排水性鋪裝技術指針之現地透水量規範所要求的400 ml/15sec，顯現出在未來實務應用上將有良好之透水績效。
並列摘要
The over development and use of impervious pavement in Taiwan, causing rapid loss of surface runoff, endangers water conservation. The porous asphalt concrete has merits in water retention, cooling, and improving drainage, however, with the increase in traffic and age, the pavement will gradually reduce its drainage function after the pores clogged, which is one of the major problems. Losses of porosity in porous concretes can be classified as pore clogging and pore closing. The clogging is mainly caused by flying dust, sand, or fretting pellets carried by vehicle, and pore closing is often due to the cumulative vehicle load and rearranging of the pores or particles. The research would simulate clogging effect induced by falling dust and soil clumps on porous concrete and explore the changes of permeability after rainfalls. It has four groups of porous concrete proportion in the study, containing waste incinerator bottom ash as fine and coarse aggregates and cement consumption with 130 kg/m3 and 200kg/m3 respectively. In situ permeability of the four proportion groups, before the dust simulation test, falls between 1399.75~1412.91 ml/15sec. Simulation of dust fall uses the monthly average dust fall in Pingtung Hsien, 2011, and its 10 folds, 20 folds increments to study the clogging due to natural dust fall after seasonal rainfall. The clogging simulation of soil clump, up to 30 folds of the average monthly dust fall, dumped on the pavement are also tested. According to the results, the natural dust fall rarely clogs the porous concrete, while the soil clumps which is higher than 15 folds of the monthly average dust fall drops the pavement permeability significantly, but it is still higher than 400 ml/15sec, the Japanese Drainage Pavement Technical Indicators requirements. It shows, in practical use, the porous pavements will mostly maintain good permeable performance under the inevitable dust fall.