摘要
为了改良路填花岗岩残积土物理力学性能,同时考虑改良的经济效益,通过掺加低配比的煤矸石粉来提高路填土的强度,为工程实际应用提供依据。通过花岗岩残积土掺加9%、12%、15%与18%掺量的煤矸石粉开展路填土无侧限抗压强度试验,分别得到14、21、28、35 d的无侧限抗压强度值,利用最小二乘法分别分析了煤矸石粉掺量与养护龄期对路填土的无侧限抗压强度的影响,结果表明:随着养护天数的增加不同煤矸石粉掺量的花岗岩残积土无侧限抗压强度随着应变的增加先增加后减小,呈应变弱化型。不同掺入量、养护天数条件下花岗岩残积土应力应变之间呈二次多项式关系。在掺量低于12%条件下,煤矸石粉掺入量与抗压强度的关联性不强,掺入量超过12%后,不同掺入量与无侧限抗压强度之间呈二次多项式关系。无侧限抗压强度与养护天数呈二次多项式关系。煤矸石粉掺量与养护天数的无侧限抗压强度呈曲面相关。煤矸石粉改良花岗岩残积土最优掺量为9%,最优养护龄期为28 d。
In order to improve the physical and mechanical properties of road-filled granite residual soil with economic benefits of improvement considered,the strength of road fill is improved by adding low proportion of coal gangue powder,which provides a basis for practical application of the project.In this paper,the unconfined compressive strength test of road fill is carried out by adding 9%,12%,15%and 18%coal gangue powder to granite residual soil,and the unconfined compressive strength values of 14 days,21 days,28 days and 35 days are obtained respectively.The influence of the coal gangue powder content and the curing age on the unconfined compressive strength of the road fill is analyzed by the least square method.The results show that:as the curing days increase,the unconfined compressive strength of the granite residual soil with different amount of coal gangue powder increases first and then decreases with the increase of strain,showing a strain weakening type.Besides,there is a quadratic polynomial relationship between the stress and strain of granite residual soil under different mixing and curing days.When the blending amount is less than 12%,the correlation between gangue powder content and the compressive strength is not strong.When the blending amount exceeds 12%,there is a quadratic polynomial relationship between the coal gangue powder content and the unconfined compressive strength.In addition,the unconfined compressive strength has a quadratic polynomial relationship with the number of days of maintenance.And the relationship between the content of coal gangue powder and the unconfined compressive strength is curved.On the whole,the optimum dosage of gangue powder modified granite residual soil is 9%,and the optimal curing age is 28 d.
作者
俞旺新
张恩
YU Wang-xin;ZHANG En(School of Earth Sciences and Geological Engineering,Sun Yat-Sen University,Guangzhou 510275,China;Guangdong Key Laboratory of Geological Processes and Mineral Resources Exploration,Guangzhou 510275,China)
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2020年第3期598-605,共8页
Journal of Guangxi University（Natural Science Edition）
基金
国家重点开发项目(2017YFB1201102)
广东省自然基金资助项目(2018A0303130154)。
关键词
花岗岩残积土
抗压强度
相关性
多项式
Granite residual soil
compressive strength
correlation
polynomial
