夯實對風化泥岩剪力強度之影響

The Influences of Shear Strength on Weathering Mudstone with Different Compacted Characteristics

許中立(Chung-Li Hsu) ； 陳慶雄(Ching-Hsing Chen)

《坡地防災學報》 2卷2期 (2003/12) Pp. 15-26

https://doi.org/10.29995/JSHR.200312.0002

摘要

青灰泥岩主要分佈於台灣西南部之丘陵地帶，其工程特性介於土壤與岩石之間，遇水易膨脹而崩解，常導致嚴重之沖蝕與崩塌現象。在土地資源極爲有限的台灣，泥岩地區可進行開發農場、社區及興建道路等，惟仍涉及大量的土方挖填作業，本文即以夯實填方材料爲題，探討夯實後其飽和及未飽和之剪力強度變化。採用材料爲高雄縣田寮鄉月世界之泥岩，爲避免試樣之顆粒過粗，乃採磨碎通過#4號篩後進行試驗。研究結果顯示泥岩在磨碎之後其夯實特性與一般土壤夯實行爲類似；在含水量10%左右，夯實能量的增加使乾密度增加之效益較大；在含水量20%左右，增加夯實能量並不能有效使乾密度增加。未浸水飽和時，乾側試體較濕側試體有較大的剪力強度；浸水飽和後，試體之剪力強度則較小。在未浸水飽和時，以高夯實能量情況具有較高的剪力強度；浸水飽和後，夯實能量的大小對剪力強度之影響降低。

關鍵字

泥岩 ； 夯實 ； 剪力強度 ； 浸水

並列摘要

Mudstone, almost with green gray color, which lay at the hill of southwest Taiwan areas, has the engineering characteristics between soil and rock, which structure quickly collapse on soak, thus many slope disasters occurred in this areas. This areas need be built as farms, residential districts and roads in part because of limited space of landuse development. There are many magnitude cut and fill works in this development regions, especially, the residual soil re-compacted always filled in deep land or road embankment, but their shear strength with different compacted characteristics became more important for stability. The research used the material, passing #4 sieve for avoiding many gravels, from the moon world at Tienliao village in Kaohsiung county, focus on the shear strength change with different compacted and soak condition. The results show that the broken or weathering mudstone characteristics almost like soil, increase compacted energy caused buck density increasing rapidly in soil moisture about 10% conduction but in soil moisture about 20% conduction this phoneme was not obvious. The shear strength of compacted test dry side was greater than wet side before soak in water, but when soil was saturated the dry side shear strength would decreasing rapidly. Otherwise, the shear strength increased with compacted energy before soak in water, but when soil was saturated this influence would decreasing.

並列關鍵字

Mudstone ； Soil compacted ； Shear strength ； Soak