Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/33334
標題: 崩塌邊坡岩石特性與破壞時間之探討
Studies on Rock Characteristics at Landslide Sites and on Creep Timing
作者: 李正義
Lee, Cheng-Yi
關鍵字: rock characteristics;岩石特性;landslide;creep timing;崩塌地;破壞時間
出版社: 水土保持學系
摘要: 
This study was conducted to investigate and discuss the
causes, rock characteristics at three landslide sites in
the Tsengwen Reservoir Watershed in the south Taiwan. The
prediction equation for the failure timing of lands lides is
also developed. The research method used in this study include
Petrographic Microscope, X-ray Diffraction (XRD), Scanning
Electron Microscope(SEM), Inductively Coupled Plasma
Spectroscope (ICP), Constant Head Permeameter in
Triaxial Apparatus,Seismic Exploration by wave-refraction
processes. The results are summarized as follows:
1. The Da-Pang landslide is an arc-shape creep type. The causes
are the risingwater table by infiltrated rainfall that increased
the pore-water pressure, steep topography and road
construction. The site is in the Neogene Middle Miocene Da-
Pang (Nankuang F.)Formation mainly made up of mud shale and
calcareous siltstone. The rock-forming mineral contents of mud
shale include sericite, quartz, calcite, that of calcareous
siltstone include quartz, calcite, sericite and feldspar.
2. The Ta-Tou landslide, another arc-shape type creep, are
caused by road construction, concentrated runoff, steep
slope due to gully head erosion, and increased pore-water
pressure due to increased subsurface moisture and poor
drainage. The site is located at Neogene Late Miocene Nanchuang
Formation with calcarenite and calcilutide minerals include
quartz, calcite, sericite, feldspar and quartz, sericite
calcite. 3. Mao-Pu-Tse
landslide is also an arc-shape type failure. It was caused by
undercutting of slope by fluctuating reservoir water levels and
liquefaction of slopeland submerged in water over long period
of time. The Neogene Late Miocene Kueichulin (Ta-Wo sandstone
member) Formation at the site is composed of siltstone and fine
greywacke. Its minerals include quartz, sericite,
feldspar.
4. The results of chemical analyses for whole minerals indicate
a higher Na content that of K at all three landslide sites.
The iron normally occur as Fe5. The relationships between
percolation velocity (V) and gradient (i)are: a. For
different pressures at the same depth
Ⅰ Da-Pang landslide site V=0.0100~0.0138 i
Ⅱ Ta-Tou landslide site V=0.0146~0.0211 i
Ⅲ Mao-Pu-Tse landslide site V=0.0099~0.0207 i
b. For different depths at the same pressure
Ⅰ Da-Pang landslide site V=0.0121 i
Ⅱ Ta-Tou landslide site V=0.0211 i
Ⅲ Mao-Pu-Tse landslide site V=0.0144 i
6. The prediction equation for the failure timing developed from
surface extensometer is with eight sets of data at six
landslide site. log tr = 4.018-0.3466*log(
e''*10^4) where tr is
the failure timing

本論文主要目的乃是探討台灣曾文水庫集水區崩塌邊坡岩石之基本特
性與邊坡破壞時刻之預測式推估。運用之方法有岩石薄片偏光顯微分析、
X 光線繞射法、岩石微構掃描式電子光束顯微觀測、感應耦電漿發射光譜
法之全岩分析、岩石三軸定水頭透水試驗、邊坡破壞時刻之預測以及震測
法之應用等。試驗分析所得之結果如下: 1.達邦崩
塌地為圓弧形層狀滑動型態,引起崩塌的原因為雨水入滲地層而使地下水
位提高,孔隙水壓增大而致抗剪強度減低,其次為地形陡峭,加上道路開
挖,更激發其滑動。又本地區為中中新統南港層,岩性有頁岩(泥頁岩)
及粉砂岩(鈣質粉砂岩)二種,其組成礦物主要為石英、方解石、絹雲母
以及長石(粉砂岩類造岩礦物),而頁岩之主要造岩礦物為絹雲母(粘土
礦物的一種)、石英及方解石。
2.獺頭崩塌地亦屬圓弧型層狀滑動型態,造成崩塌之原因則為修築道路,
逕流集中,本身坑溝坡降大,呈現出很強的向源沖蝕力,使得抗剪強度減
低,崩積層含水量增高,自然排水不易,孔隙水壓增大等特性,遂引起滑
動現象。又本地區為晚中新統南莊層,岩性分為,鈣質粉砂岩及鈣質細粒
砂岩,其主要組成礦物分別為石英、方解石、絹雲母、長石,以及石英、
絹雲母、方解石。
3.茅埔仔崩塌地亦為圓弧型之滑動型態,滑動平面形狀為馬蹄形地滑,引
起崩塌的原因為坡趾受水庫之蓄水淘刷與長期浸泡軟化而失去側部支撐所
致。又本地區為晚中新統-上新統桂竹林層,岩性分為灰色粉砂岩及淡灰
色細粒砂岩二類,組成礦物主要為石英、絹雲母、長石及方解石。
4.達邦、獺頭以及茅埔仔三處崩塌地岩石之全岩化學分析以含量鈉高於鉀
含量最為突出,鐵的含量則以三價離子狀態存在為最普遍。
5.達邦、獺頭以及茅埔仔地區崩塌岩石之滲流速度與壓力梯度間之關係如
下:(v=LT^-1 ,i=LL^-1) 相同深度不同壓力之條件下:
達邦崩塌地區 v=0.0100∼0.0138i
獺頭崩塌地區 v=0.0146∼0.0211i
茅埔仔崩塌地區 v=0.0099∼0.0207i
相同壓力不同深度
達邦崩塌地區 v=0.0121i
獺頭崩塌地區 v=0.0211i
茅埔仔崩塌地區 v=0.0144i
6.經地表伸縮移動資料,獲得邊坡崩壞時程預估式為:
log tr = 4.018-0.3466*log(ε''*10^4)
式中tr :為破壞時間(T)
ε'' :為應變速率(T^-1)
7.本研究為了解崩塌體之地下構造乃嘗試採用震測折射法,配合茅埔仔崩
塌地之地質鑽探與現場監測資料比較,以供進一步崩塌機制之探討。
URI: http://hdl.handle.net/11455/33334
Appears in Collections:水土保持學系

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