土壩壩型與滲流破壞之模型試驗

Model Experiment of Earth Dam Type and Seepage Break

許中立(Chung-Li Hsu)

《坡地防災學報》 9卷1期 (2010/10) Pp. 11-20

https://doi.org/10.29995/JSHR.201010.0002

摘要

土壩壩型取決於現地基礎條件、材料來源與數量、氣象水文、經濟性與施工性等因素。而土壩壩體必須具備穩定、低透水與少變形之性質，故土壩材料之選取以具低壓縮性、高剪力強度、低透水性者為佳。土壩在上游貯水位保持固定時，會因水位差而產生滲流現象，然土壩壩體內部的滲流力通常是造成壩體破壞的主要因素之一。本研究係以砂箱模型試驗，探討不同頂底比率之模型土壩安定與滲流線特性。試驗結果顯示底部越寬之模型土壩之安定性越高，且其形成之滲流面也與理論值越接近，惟達到穩定滲流的所需時間較長；在相同壩型條件下，後方的貯水位越高則實驗破壞時間越短。

關鍵字

土壩 ； 壩型 ； 模型試驗 ； 滲流 ； 安定性

並列摘要

The type of the earth dam depends on the factors, such as basic condition, material source and quantity, weather condition, economy and constructing, etc. And the earth dam body must possess the stability, low permeable, few displacement of shape, so the choosing of earth dam material had low consolidated, high intensity of shear strength, low water permeability. When earth dam the water level of the upper stream keeps regular, will produce the influent phenomenon because of water level difference, but the influent strength within the dam body is usually to cause one of the main factors that the earth dame slope will be destroyed. This research used the sand box, probe into the dame stable and influent seepage wetting lines with different shape types of dam top and bottom. The results of the test show that the earth dam stability in the bottom wider model is relatively high, and its seepage surface relatively close to theory value, only the time to stabilize seepage is relatively longer. Under the terms, the store water level rising high will let dam break time shorter in the same earth dam type conduction.

並列關鍵字

Earth dam ； Dam type ； Model experiment ； Seepage ； Stability