不同环境条件下堆石料变形特性的试验研究

Experimental study of deformation characteristics of rockfill under different environmental conditions

探讨了对处于受压状态的堆石料进行干湿、冷热变化等环境因素作用下力学性质研究的试验方法。使用新研制的堆石料风化试验仪,对某种泥质粉砂岩堆石料进行了干湿循环、冷热循环以及湿冷-干热耦合变化三种环境条件下的长期变形特性试验研究,探讨了堆石料长期劣化变形的机制。试验结果表明,干湿循环试验和湿冷-干热耦合循环均可导致堆石体产生较大幅度的附加变形,其变形机制包括湿化变形、堆石体颗粒湿胀和干缩循环变形以及堆石料的劣化变形等。环境因素的循环变化可导致堆石体颗粒的劣化,堆石体劣化变形是高土石坝后期变形的重要组成部分。

An experimental method to investigate the long-term mechanical characteristics of loaded rockfill under different environmental conditions of drying and wetting,cooling and heating is presented.A series of tests were performed by using a newly developed weathering test apparatus to study the long-term degradation strain mechanism of argillaceous siltstone rockfill under different environmental conditions including drying and wetting cycles,cooling and heating cycles and the coupled wetting-cooling and drying-heating cycles.The test results show that the drying and wetting cycles and the coupled wetting-cooling and drying-heating cycles can induce remarkable additional strains of loaded rockfill,including wetting strain,wet-swelling and dry-shrinking strain and rockfill particle degradation strain.It is shown that the changes of environmental factors can cause degradation of rockfill particle;and the degradation strain of rockfill is a key portion of the long-term strain of high rockfill dam.