西南山区交通工程弃渣的工程特性评价及其分类

山区交通工程弃渣力学参数的准确测定,一直是弃渣场边坡稳定性评价面临的基础科学问题。在山区交通工程弃渣场运行特点和弃渣固体废弃物特征认知的基础上,探讨弃渣取样和试验代表性问题的物理根源,依托实际工程累计数据尝试提出简单实用的弃渣工程特性评价和分类方法。结果表明:①常规交通工程弃渣的密度、颗粒分析和强度试验,由于弃渣的粒径范围差异大、颗粒空间分布不均、弃渣来源复杂等固体废弃物特征造成取样和试验代表性难题; 用多阶段坡角测量和颗粒分析试验代替传统的弃渣边坡试验,解决了试验和取样代表性难题。②利用弃渣粗细比可将弃渣分为细粒弃渣、混合型弃渣和粗粒弃渣。③根据弃渣粗细比、天然休止角和整形坡率,将西南山区交通工程弃渣分为细粒弃渣、混合型弃渣和粗粒弃渣等3类。细粒弃渣,弃渣粗细比小于0.3,天然休止角小于31.5°,整形坡率为1.00:2.00; 混合型弃渣,弃渣粗细比为0.3～1.0,天然休止角为31.5°～39.5°,整形坡率为1.00:2.00～1.00:1.50; 粗粒弃渣,弃渣粗细比大于1.0,天然休止角大于39.5°,整形坡率为1.00:1.50。④用多阶段坡角测量、颗粒分析试验和无黏性土边坡稳定性系数计算公式代替传统的弃渣边坡试验和稳定性系数计算方法,方法简单,结果保守,可以作为弃渣边坡稳定性评价和安全控制技术的有益补充。

Classification and Estimation of Engineering Properties for TrafficEngineering Waste Slag in Mountainous Areas of Southwest China

Accuracy measurement of traffic engineering waste slag in mountainous area is always a basic scientific problem of spoil ground stability estimation. On basis of traffic engineering spoil ground working feature and solid waste characteristics of waste slag, the representative problems' root of sampling and test was discussed. According to practical engineering, a simple practical classification and estimation method was studied. The main conclusions are following. ①Solid waste characteristics, such as large difference in particle size range, uneven spatial distribution of particles and complex sources of waste slag, result in their sampling and test result representative problems; multi-stage slope angle measurement and particle analytical test can be used to replace common experiments of waste slag slope, which solves the above two representative problems. ②Ratio of coarse and fine (k) is defined as coarse particles gravity divided by fine particles gravity, which divides waste slag into fine grain, mixed grain and coarse grain. ③According to the ratio of coarse and fine, natural repose angle and reshaping slope ratio, the traffic engineering waste slag in mountainous area of Southwest China can be classified into the above three types; the fine grain waste slag's k is less than 0.3, natural repose angle being less than 31.5°, reshaping slope ratio being less than 1.00:2.00; the mixed grain waste slag's k is larger than 0.3 and less than 1.0, natural repose angle being larger than 31.5° and less than 39.5°, reshaping slope ratio being larger than 1.00:2.00 and less than 1.00:1.50; the coarse grain waste slag's k is larger than 1.0, natural repose angle being larger than 39.5°, reshaping slope ratio being less than 1.00:1.50. ④The methods combined multi-stages slope angle measurement, particle analytical test and slope stability coefficient formula for non-cohension soil, which are presented to replace common test and waste slag slope stability estimation method, are simple and conservative, and can be used in traffic engineering waste slag slope stability estimation and safety control.