【摘要】 在水工建筑物附近进行大规模爆破施工时,爆破产生的振动效应直接影响水工建筑物的安全稳定。针对侧向爆破荷载作用下邻近厂房高端墙的振动效应展开研究,结合萨道夫斯基公式和薄板模型建立了反映中心放大效应的高端墙爆破振动峰值预测模型,以深溪沟水电站灌排洞爆破开挖为例,分析了灌排洞爆破施工在邻近厂房高端墙产生的振动空间分布特征,并采用实测爆破振动数据对预测模型进行了训练和检验;基于确定的高端墙爆破振动安全控制标准,对侧向爆破荷载作用下地下厂房高端墙安全性进行了分析。研究结果表明:爆破应力波传至地下厂房高端墙时会发生反射,反射回来的应力波与入射应力波叠加,会加剧高端墙的振动效应,呈现出非常明显的中心放大现象;保障厂房高端墙安全的关键在于控制其中心的爆破振动峰值,尤其要严格控制垂直于高端墙方向的爆破振动幅值,不得大于1.2 cm/s(以C20标号的混凝土厂房为例),从而避免高端墙发生张拉破坏。更多还原

【Abstract】 During construction large-scale blasting near the hydraulic structures may cause strong vibration directly affecting the safety and stability of hydraulic structures. The vibration effects on the high-end wall of a underground powerhouse under the action of lateral blasting load was studied. Combining the Sadowski formula with a thin plate model, a prediction model for the blasting vibration peak value on the high-end wall was established which can reflect the central amplification effect. Taking the blasting excavation of a grouting and draining tunnel at Shenxigou hydropower station as an example, the spatial distribution characteristics of blasting vibration on the high-end wall caused by the blasting excavation were analyzed, and the prediction model proposed was trained and tested using the measured blasting vibration data. Based on the safety control standard of blasting vibration, the safety of high-end wall of the underground powerhouse under the action of lateral blasting load was analyzed. The results show that when the blasting stress wave transmits to the high-end wall, it will be reflected. And the superposition of the reflected and the incident stress waves will aggravate the vibration effect on the high-end wall, leading to a very obvious phenomenon of center amplification. The key to ensure the safety of the high-end wall is to control the peak value of blasting vibration at its center, especially to strictly control the blasting vibration perpendicular to the high-end wall. The vibration amplitude should not be greater than 1.2 cm/s(for C20 labeled concrete powerhouse), and the tension failure of the high-end wall can be avoided.更多还原