INVESTIGATION OF THE INTERNAL STABILITY AND ACTIVE EARTH PRESSURE DISTRIBUTIONS OF SUPERIMPOSED GEOSYNTHETIC REINFORCED EARTH WALLS

雙階式加勁擋土牆的內部穩定及主動土壓力分佈研究

洪汶宜(Wen-Yi Hung) ； 范日方(Truong-Nhat-Phuong Pham) ； 王信偉(Hsin-Wei Wang)

《中國土木水利工程學刊》 32卷2期 (2020/04) Pp. 171-185

https://doi.org/10.6652/JoCICHE.202004_32(2).0005

摘要

In recent times, a vast number of construction projects that are relevant to geotechnical engineering have been designed and are executed annually. Generally, ＂retaining structures＂, in terms of wall structure and stiffness, they can be divided into several types: monolithic retaining walls (gravity retaining walls or masonry), precast retaining walls, gabion walls or reinforced earth wall. Reinforced earth structures are mainly established to protect significant existing structures such as highways, coastlines, military installations and so on. The design methods for the construction of reinforced earth walls are quite diverse depending on different wall inclinations, from one tier to multi-tier. In this context, the design of two-tiered reinforced earth walls or superimposed geosynthetic reinforced earth walls (SGREW) is widely preferred because of their simple configuration and load-bearing capacity. In previous studies, the internal stability of SGREW has been designed based on the maximum tensile force lines which were derived geometrically and empirically. Based on the experimental results, the modified lateral earth pressure method and the reinforced earth structure stability method can be applied to design the SGREW in terms of breaking failure behavior. This study aims to clarify the actual workings, failure behaviors and internal stability design of SGREW, simultaneously offering recommendations for ease of future designs with ease.

關鍵字

superimposed geosynthetic reinforced earth wall ； modified active earth pressure coefficient ； stability analysis ； breaking failure behavior

並列摘要

近年來大地工程結構物的發展日益興盛，以擋土系統的發展來說，依據結構類型及勁度大小可將加勁擋土結構物分成重力式擋土牆、堆疊式石牆、預鑄牆面擋土牆、蛇籠及加勁擋土牆等。加勁擋土牆可用來保護及穩固高速公路、碼頭或軍事基地等重要的結構物，且基於牆面坡度設計考量，加勁擋土牆可以分為單階或多階式擋土牆，而雙階式加勁擋土牆（SGREW）因施工容易且承載性能優異，近十幾年來也被廣泛使用。雙階式加勁擋土牆多依據現場幾何條件與理論或經驗的土壓力分布進行設計，本研究的目的為釐清雙階式加勁擋土牆中的力學機制、破壞行為以及其內部穩定性分析，基於內部斷裂破壞行為的條件下，提供建議的修正側向土壓力法，以及加勁檔土結構物穩定分析法，應用於設計雙階式擋土牆的尺寸與穩定性評估。

並列關鍵字

雙階式加勁擋土牆 ； 修正主動土壓力係數 ； 穩定性分析 ； 斷裂破壞行為