流速对黄河抢险险工抛投体稳定性影响及对策

Effects of Flow Velocity on Stability of Gadions at Vulnerable Spots in Yellow River Emergency Rescue and Its Countermeasures

通过对黄河险工和控导工程防汛抢险中抛投材料大量走失原因进行分析,并以铅丝石笼为研究对象,建立了抛投体在动水中的受力分析模型。在对抛投体进行受力分析的基础上,研究险工流速、水深等对抛投体稳定性的影响规律,结果表明:抛投法抢险中,险工处瞬时流速越大、水深越大,抛投体在动水中的位移就越大,稳定性就越差;增加抛投体的质量(体积),能够有效减小抛投体在动水中的位移,增强其稳定性;设计合理质量的抛投体、预留足够的抛投距离或采用链接抛投体等措施能够确保黄河防汛抢险中抛投体的稳定性。

In this paper,the causes of mass loss of throwing materials in flood control of the Yellow River were analyzed and the stress analy⁃sis model of throwing body in moving water was established with gabion as the research object.Based on the force analysis of gabion,the in⁃fluence of the velocity and depth of the dangerous section to the stability of the throwing materials was studied.The results show that increas⁃ing velocity and water depth can lead to poor stability of the throwing materials in the dynamic water and increasing weight(size)of throwing materials can effectively reduce the displacement and enhance its stability.Finally,some measures are put forward,such as designing a rea⁃sonable weight throwing materials,reserving enough throwing distance or using linked gabion system to ensure the stability.