高烈度区斜坡震裂变形体广泛存在，为理清台阶式顺层岩质边坡在多期地震作用下的震裂破坏机制，以三清高速路堑斜坡为原型，开展大型振动台试验。引入加速度放大系数比（ratioof acceleration amplification factor，RAAF）研究不同台阶位置加速度动力响应差异性，利用希尔伯特−黄变换和边际谱识别边坡震裂累积损伤及失稳破坏过程，结合边坡失稳破坏现象阐明台阶式边坡震裂破坏机制。结果表明：边坡具有高程放大效应，加速度放大系数随输入地震波峰值增加呈现先增加再降低的趋势。RAAF在输入地震波峰值为0.6g前后出现正负突变，表明输入地震波峰值为0.6g是改变两种类型边坡动力响应差异性的“临界值”。多期地震作用下，希尔伯特谱低频部分减小，高频部分增加，岩体和夹层表现出滤波作用。水平地震作用下，台阶阴角极易产生动拉应力集中，造成阴角处被拉裂。不均匀台阶宽度边坡的渐进破坏过程为第2级台阶首先出现拉裂缝→上部岩层沿软弱夹层滑动→坡顶后缘拉裂→第1级台阶拉裂并脱离坡体。均匀台阶宽度边坡各级台阶阴角均出现拉裂缝，边坡未出现明显滑动面。模型试验揭示了台阶式岩质边坡的震裂破坏机制，针对勘察设计和施工应加强各级台阶阴角变形量的监测，阴角处可做圆弧处理降低应力集中现象。坡脚处可设置抗滑桩，提高边坡出现震裂破坏的阈值，增强边坡稳定性。The shattering deformation masses in high seismicintensity area are widely distributed. In order to understand the shatteringfailure mechanism of step-like bedding rock slopes under multi-stage earthquakeexcitations

a large-scale shaking table test is conducted based on the cutslope of Sanqing Expressway. The ratio of acceleration amplification factor(RAAF) is proposed to investigate the difference of acceleration dynamicresponse at different positions

while the Hilbert-Huang transform and marginalspectrum are used to identify the cumulative damage effect and failure process.Combined with the slope failure phenomenon

the shattering failure mechanism isclarified. The results show that the slope has an elevation amplificationeffect

and the acceleration amplification factor tends to increase first andthen decrease with the increase of the input peak seismic wave. TheRAAF undergoes a positive-to-negative mutation before and after the 0.6g input seismic wave peak

which is thecritical value for changing the dynamic response between the two slope types.Under multi-stage earthquake excitations

the low-frequency component of theHilbert spectrum decreases while the high-frequency component increases

indicating a filtering effect of rock mass and interlayer. Under horizontalseismic excitation

the internal corners of the step are easy to exhibitdynamic tensile stress concentration

resulting in the internal corners proneto be shattered. For the slope with uneven step width

theprogressive failure processes involve the second step being shattered firstly

followed by the upper rock mass sliding along the weak interlayer

the rearedge of the slope top being pulled apart

and finally

the first step beingpulled apart and separated from the slope body. For the slopewith even step width

the cracks appeared at the internal corners of each step

while there was no obvious sliding surface. The shaking tabletest reveals the shattering failure mechanism of step-like bedding rock slopes.In survey

design

and construction

it is significant to pay attention to thedeformation at the internal corners of each step and apply an arc treatment toreduce stress concentration. Additionally

anti-slip piles can be installed at the slope toe to increase the threshold forshattering failure and enhance stability of the rock slope.