铁山港航道Ⅲ标段疏浚工程造成的水动力改变研究

Study on Hydrodynamic Changes and Sediment Diffusion Caused by Dredging Project in Section Ⅲ Channel of Tieshan Port

关键词:  铁山港  疏浚  水动力  潮流  流速

Key words:  Tieshan Port  dredging project  hydrodynamics  tide  velocity

摘要:

铁山港作为广西北部湾经济区中转运输枢纽港区，其拓宽浚深工程对港区发展意义重大。本研究基于MIKE21数值模型，在Ⅲ标段疏浚工程光滩和红树林区域采用不同的曼宁系数，计算工程前后水动力的改变情况。结果表明：工程建设前，航道附近涨急最大流速为50.4 cm/s，落急最大流速为68.2 cm/s；工程建设后，航道附近涨急最大流速为41.3 cm/s，落急最大流速为59.1 cm/s。航道两端流速变化较大，其中北端涨急变化率在10%以上，最大变化率为-77.0%；北端落急流速变化率在20%以上，最大变化率为-31.5%。红树林区域流速基本以降低为主，涨急时刻降低幅度较大，最大为-84.0%；落急时刻降低幅度较小，最大为-13.0%，疏浚工程实施后使得红树林区域的流速有所降低。

Abstract:

Tieshan Port is a transshipment hub port area of Guangxi Beibu Gulf Economic Zone, and its widening dredging depth project is of great significance to the development of the port area.In this study, based on the MIKE21 numerical model, different Manning coefficients were used in the beach and mangrove areas of the dredging project in Section Ⅲ to calculate the hydrodynamic changes before and after the project.The results showed that before the construction of project, the maximum flow velocity of surge near the channel was 50.4 cm/s, and the maximum flow velocity of fall near the channel was 68.2 cm/s.After the construction of the project, the maximum flow velocity of sharp rise near the channel was 41.3 cm/s, and the maximum flow velocity of sharp fall near the channel was 59.1 cm/s.The flow velocity changes greatly at both ends of the channel, in which the rate of sharp rise at the northern end was more than 10%, and the maximum change rate was -77.0%.The change rate of sharp fall velocity at the northern end was above 20%, and the maximum change rate was -31.5%.The flow velocity in the mangrove area was basically decreased, and the decrease was larger at the moment of sharp rise, with the maximum of -84.0%.At the moment of sharp fall, the reduction range is smaller, with the maximum of -13.0%.After the implementation of the dredging project, the flow velocity in the mangrove area was reduced.