雜物含量、粒度對剩餘土石方工程性質之影響

• Main Author: 吳信龍
• Other Authors: 楊朝平
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/21794745085763492163

碩士 === 中華大學 === 土木工程學系碩士班 === 90 === In recent years the by-product materials are growing more and more in Taiwan, we can solve the disposing society problems and make them become the substitution of the construction foundation to reducing the environmental impaction by reusing them. But the by-product materials first must be classified and cleared out the debris (ex. the chippings of wood, metal, plastic and rubber, class and paper etc.) to become the excess construction soil (ex. the mass of cement, tile, china and soil etc.) and reuse them after reclamation. Because classification and reclamation are the keys of recycling, so it is very important to investigate the influences of debris content or gradation of the excess construction soil for the engineering properties and suggest the proper permission value of debris content and gradation by the influences. By the reason we not only investigate the grain-size distributions and the physical properties of the excess construction soil samples from the five (Puli, Nantou, Wufung, Tali, Taiping) construction demolition wastes sites of 921 Taiwan Chi-Chi Earthquake but also observe the influences for the engineering properties of compaction, bearing capacity, impact acceleration of the excess construction soil samples by make four debris contents (0.1%, 0.5%, 1.0%, 2.0%) and six gradations. After these series studies we generalize six points: 1. The excess construction soils from five sites all have no plastic in consistency, the classifications by AASHTO system all are A-1-a, the specific gravities are between 2.40 to 2.53, mud contents of coarse part are between 1.53% to 1.67%, abrasions of coarse part are between 22.3% to 31.0%, percents of water absorption of washed coarse part are between 7.3% to 8.1%. 2. The optimum moisture content increases and maximum dry unit weight reduces when the debris content in one sample increasing, but it is more apparent in the samples with more soils such as Puli and Taiping sites; the influences of debris content in bearing capacity and impact acceleration are harder to observe; so we suggest that the permission value of debris content in the excess construction soils is 1.5% by the engineering properties of the excess construction soils. 3. The classifications by AASHTO system of the six gradations samples all are A-1-a or A-1-b, and the CBR values for dry unit weight by a factor of 0.95 all are more than the value of 35, so we suggest that all the gradations of the excess construction soils could be recycled for the needs of subgrade and base course constructions. 4. For the samples of the same dry unit weight in the one curve of compaction, the value of impact acceleration of the sample in dry side is more than optimum one, and it is minimum in wet side. 5. For the samples of four debris contents from five sites and six gradations,the correlation coefficients are between 0.70 to 0.99 in the relation of impact acceleration and CBR and between 0.74 to 1.0 in the relation of impact acceleration and dry unit weight, which are more than the correlation coefficients for all the samples of four debris contents from five sites and six gradations between 0.41 to 0.81 in the relation of impact acceleration and CBR and between 0.33 to 0.79 in the relation of impact acceleration and dry unit weight. 6. According to point 4 and 5 for the quality of impact acceleration, we may account that the relations of impact acceleration and CBR or impact acceleration and dry unit weight for the samples of the same optimum moisture content of one site or one gradation are better; but impact acceleration could be effected by the varieties of soil samples and their moisture contents, i.e. the relations of impact acceleration and CBR or impact acceleration and dry unit weight are unapparent. Seriously it is usable in one variety of soil with the same moisture content. If we would use impact acceleration to estimate the quality of compaction indirectly or predict bearing capacity in work sites, we should first make certification experiments of impact acceleration in laboratory. Keywords: Excess Construction Soil, Gradation, Debris Content, Compaction, Bearing Capacity, Impact Acceleration.