水化CFB副產石灰應用於鋪面底層之可行性分析

Abstract

本研究利用高溫循環式流體化床發電鍋爐(Circulating Fluidized Bed Boiler，簡稱CFB) 所產生之CFB副產石灰，根據公共工程委員會所訂第02726章級配粒料底層規範摻配製作級配粒料，以不同添加比例設計一系列底層級配配比，透過相關試驗探討添加水化CFB副產石灰應用於級配粒料底層之可行性。 研究結果顯示，水化CFB副產石灰做為道路底層材料： (1)根據統一土壤分類法及AASHTO分類法，為適用於道路底層之材料。 (2)所有實驗設計配比之最大乾密度、加州承載比值及膨脹百分比等皆符合施工綱要規範之要求。 (3)以粗粒料60%、水化CFB副產石灰30%、細粒料10%時之加州承載比值表現最佳。 (4)當水化CFB副產石灰膨脹時，行為為先填充孔隙。 當級配設計良好時，添加水化CFB副產石灰於道路底層是可行的。

In this study, we designed a series of base course mixture ratios by mixing different proportion of the by-products of circulating fluidized bed boiler, coarse aggregate and fine aggregate according to Standard Specification for Graded Aggregate Materials for Base Course. Through the relevant test results we find that is feasible to use hydrated CFB ashes in pavement base course. By using hydrated CFB ashes in pavement base course, we can conclude： (1)CFB ashes can be classified as usable to U.S. Bureau of Reclamation's Unified Soil Classification System and AASHTO Classification System. (2)Maximum dry density, California Bearing Ratio and expansion percentage of all designed base course mixture ratio fully meet the requirements. (3)The best mix proportion is 60% of coarse aggregate, 30% of hydrated CFB ashes and 10% of fine aggregate. (4)After expansion due to water, hydrated CFB ashes will fill the pore first. (5)With the allowed aggregates from specifications, using hydrated CFB ashes in base course is workable.