高水材料充填体强度检测与分析

Strength test and analysis on high-water material backfill

为了准确掌握高水材料充填体的强度变化规律,基于875批次的养护和井下取心试样进行了充填体单轴强度检测,利用方差分析和回归分析研究充填体的单轴强度规律,并根据不同龄期试样不同围压条件下的检测数据分析了充填体的力学性能和围压条件下的破坏特征。结果表明:充填体7 d平均强度为2.55 MPa,14 d平均强度为3.88 MPa,28 d平均强度可达4.86 MPa(为6个月强度的78.9%);充填体单轴抗压强度随时间呈S形曲线增长,回归公式为Y=e^((1.772-4.818/t));充填体的承压能力随着围压的增加大幅增加,应变也相应增加,在相同轴向压力作用下,试件的轴向应变随所受的围压增大而减小;三轴压缩条件下充填体强度σ_1与围压σ_3、试件单轴抗压强度f_c的拟合关系为σ_1=4.49σ_3+0.87f_c。对于相同龄期的充填体,随着围压的增大,比率σ_1/σ_3呈逐渐减小的趋势。

In order to accurate master strength variation law of high-water material backfill,the law of this paper,with variance analysis and regressive analysis based on the 875 batch uniaxial strength inspectproperties and failure characteristics of backfill were researched aiming at the inspectResults show that,average intensity of 7days,14 days and 28 days is respectively erage intensity 78. 9% times of 6 months,. Uniaxial strength of backfill showed increasing of sigmoid curve with time,the regression for-mula was： Y = e（＇772 4＇818/t. The bearing capacity of the filling body increases greatly with the increase of confining pressure, and thestrain also increases correspondingly. Under the same axial pressure,the axial strain of the specimen decreasfining pressure. Strength of backfill.1、confining p re s s u re .and uniaxial strength /c have the fitted formulas： 〇 ＂1 = 4. 4 9〇 ＂3 ＋ 0. 8 7 7 .For the same age of filling body,with the increase of confining pressure,the ratio of oml / o m3 showed