渠道降排水方案优化设计

依据研究区水文地质条件及经验公式计算结果,对温博Ⅱ标渠道采取渠道一侧设计管井降排水并提出3种设计方案.方案1:井间距25 m,单井抽水量480 m3/d;方案2:井间距35 m,单井抽水量600 m3/d;方案3:井间距50 m,单井抽水量720 m3/d.运用Visual MODFLOW进行模拟计算,通过对3种设计方案的模拟结果进行分析,在方案2的基础上对渠道降排水方案进行优化设计,得出最优降排水方案为:渠道断面C和断面D之间井间距调整为18 m,仍采用左侧单边抽水,渠道其他各处抽水井间距仍为35 m,所有抽水井单井抽水量均为600 m3/d,总井数357口,抽水30 d后渠道水位低于控制水位98.6 m.该降排水设计方案可满足施工要求且经济合理,为指导工程施工提供了重要依据.

The Optimization Design of Channel Drainage Scheme

According to the hydrological condition in the research area and the empirical formula calculations, three kinds of channel drainage design schemes for Wenbo II bid package are given. Drain wells are designed to be arranged on one side of the channel, and the well spacing is 25 m, 35 m, and 50 m and single well yield is 480 m^3/d, 600 m^3/d, and 720 m^3/d in the three design schemes, respectively. Through the calculation of numerical simulation by using Visual MODFLOW, the simulation results of the three design schemes are analyzed and compared, then the optimal draining scheme is proposed on the basis of No. 2 scheme ： well spacing is adjus-ted to 18 m and the pumping wells are also designed on the left side of the channel between the section C and section D, while the well spacing of the other pumping wells of the channel is still 35 m, and the single well yields of all the pumping wells are 600 m^3/d. There are totally 357 pumping wells, and water level of the channel drops below the control water level of 98.6 m after continuously pumping for 30 days. The design of dewatering and drainage can meet the construction requirements and is reasonable in economy. This can pro- vide an important basis for guiding construction.