利用地基基础工程淤泥制备冷结型再生粗骨料

Using of sediment from foundation engineering to produce recycling cold-bonding coarse aggregates

台湾地区将营建剩余土石方区分为9大类,其中地基基础工程淤泥被归类为B6类营建剩余土石方,系一可再利用资源。基于资源可循环利用,本研究根据材料互制性,配合水泥化学,并导入复合材料的观念,采用冷结技术,开发以地基基础工程淤泥为母材(Matrix)的再生粗骨料,期望提高地基基础工程淤泥之再利用率及经济价值。试验结果显示,利用地基基础工程淤泥所制备的再生粗骨料性质:烘干比重约1.83;面干内饱和比重约2.12;吸水率约15.5%;单位重约1215kg·m-3;空隙率约33.5%;筒压强度介于12～18MPa;其它性质亦符合ASTMC33之要求。因此利用地基基础工程淤泥及冷结技术所开发的再生骨料,不仅符合绿建材的精神,亦可降低生产烧结型再生骨料所消耗之能源与CO2排放对环境的冲击。

In Taiwan,construction residual soils are generally sorted into 9 categories.The sediment from foundation engineering is classified as B6 construction residual soil which is a kind of recycling resource.Based on the purposes of resources recycling,this study employs the cold-bonding technique,which incorporates the principles of the cement chemistry and composite material to develop the recycling coarse aggregates using the sediment from foundation engineering as the matrix.The improvements of reusing rate and value of sediment from foundation engineering are expected.The results show that the specific gravity of recycling coarse aggregate is about 1.83 in the oven-dry(OD) state and 2.12 in the saturated-surface-dry(SSD) state;the absorption capacity is approximative 15.5 %;the dry loose density(i.e.unit weight) is around 1215 kg·m-3;the particle cylindrical crushing strength ranges from 12 to 18 MPa.For this reason,the developed recycling cold-bonding coarse aggregate presented in this paper could increase the reusing and recycling of construction wastes,reduce the energy consumption and CO2 emission resulted from producing the sintering recycling aggregates,and diminish the impact on the environment and future generations.