摘要
砂泥岩混合料浸水时效性是水位变动过程山区港口岸坡稳定分析的重要依据。利用应变控制直剪仪,设置5种工况20个试样开展不同浸水时长室内试验,分析砂泥岩混合料抗剪强度分布,得到其抗剪强度指标变化规律,查明其浸水时效性,将其用于模拟港口岸坡不同水位条件时安全性;建立港口水位上升与下降计算模型,分析了不同水位上升与下降状态时边坡安全性态。试验结果表明,砂泥岩混合料抗剪强度随浸水时间增加而减小,黏聚力随浸水时间增加先增加后趋于稳定,内摩擦角随浸水时间增加先减小后趋于稳定。由数值计算知岸坡安全系数随水位升高由0.997逐渐减小至0.952,随水位降低由0.924逐渐增加至0.994;同一水位时下降阶段安全系数降幅最大值为2.94%。因此,在不考虑渗流场影响条件下高水位时滨水港口岸坡安全性态劣于低水位状态,且在高水位时长期运行岸坡安全系数降幅最大。
Immersion timeliness of sand-mudstone mixture is an important basis for the stability analysis of slopes in mountainous portsduring the water level fluctuation process.This paper sets up 20 samples in 5 working conditions by a strain-controlled direct shear apparatus to conduct laboratory tests with different immersion durations,analyzes the shear strength distribution of sand-mudstone mixture to obtain the change law of its shear strength index,studies the immersion timeliness and apply it to simulate the safety of the port slope at different water level conditions,and establishes the calculation model of the rise and fall of port water level to analyze the slope safety behavior under the rise and fall state of water level.The test results show that the shear strength of sand-mudstone mixture decreases with the increase of the immersion time,the cohesion first increases and then stabilizes with the increase of the immersion time,and the internal friction angle decreases first and then stabilizes with the increase of the immersion time.The numerical calculation shows that the safety factor of the slope gradually decreases from 0.997 to 0.952 as the water level rises,and gradually increases from 0.924 to 0.994 as the water level decreases.At the same water level and decline stage,the maximum reduction rate of safety factor is 2.94%.Therefore,without considering the influence of seepage field,the safety behavior of the slope of waterfront port under high water level is inferior to that under low water level,and the slope safety factor decreases with largest ratio in case of long-term operation at the high water level.
作者
吴晓
WU Xiao(Anhui Urban Construction Design Institute Corp.,Ltd.,Hefei 230051,China)
出处
《人民珠江》
2020年第7期107-113,共7页
Pearl River
关键词
浸水时效性
岸坡稳定分析
水位变动
安全系数
immersion time
slope stability analysis
water level change
safety factor
