以有限元素法評估硬式透水舖面(JW工法)之結構承載力

Abstract

一般進行鋪面沉陷分析時，承載力之作用多以軸對稱方式將其簡化成二維的問題，以減少計算的複雜性。然而鋪面結構承載卻是三維的行為，因此建立一個三維的有限元素鋪面模型，可以適切地表達真實鋪面的情況。 本研究主要探討各式卡車及一般轎車之荷重對不同條件鋪面作用產生之影響，分析採用10cm、15cm、20cm及25cm之JW混凝土鋪面厚度與10cm、20cm、30cm、40cm及50cm碎石級配，並分別與路基為砂石、黏土及軟弱黏土層進行交叉分析其結構穩定。以採用有限元素法程式Plaxis3D進行分析，瞭解舖面結構之在車輛載重下之力學行為。 分析結果顯示在JW混凝土鋪面25cm搭配碎石厚度10cm條下足以承受各式車輛行駛，貯水容量則可依需求增加其厚度。

Generally,the paverment subsidence analysis usually adopts two-dimensional axial symmetric simulation to simplify the approach. However, the behavior of the load bearing on pavement structure is a three-dimensional problem. A three-dimensional finite element model is more proper to express the real conditions. This study focuses on the analysis of the response reduced by trucks and cars in general. A series arrangement of JW concrete pavement thickness by 10cm, 15cm, 20cm and 25cm with gravel grading by 10cm, 20cm, 30cm, 40cm and 50cm, respectively, under the ground surface for were simulated. The foundation, soft clay, normal clay, and sand were considerate as well. The computer program Plaxis3D was using to evaluate behavior of the pavement structure under the vehicle load applied. The result shows that a set of 25 cm thick JW concrete pavements with 10cm thick gravel above a sandy foundation can well take the loads by all kinds of vehicles. Additionally, the water storage capacity may increase by its thickness on demand.