直流输电线路工程冻土区基础施工质量控制

格尔木～拉萨±400 kV直流输电线路工程7标段位于唐古拉山脉,沿线海拔在4 600～5 300 m之间,地形、地质、气象条件复杂恶劣,全线主要不良地质为季节性冻土和多年冻土。由于冻土是一种特殊的土体,冻土区的活动层中每年都发生着季节性融化和冻结,并拌有融沉、冻胀和各种不良冻土地质现象,以致冻土基础施工完毕,基础容易产生沉降和漂移,基础根开尺寸及高差控制难度较大。7标段冻土基础施工严格按要求进行冻土开挖、切实做好混凝土防冻、采取热棒和玻璃钢模板辅助措施、严格按设计要求回填土,从而使冻土区基础施工质量得到保证。

Frozen Soil Region Construction Quality Control of Direct Current Transmission Line

Golmud ~ Lhasa ±400kV direct current transmission line project located in Tanghla sierra which has servere geology,meteorological condition as well as unfavorable geological condition such as seasonal frozen soil and permafrost regions.Foundation settlement and drifting often occurred because seasonal melting and frozen in frozen soil region as well as unfavorable frozen soil condition such as thawing settlement and frost heave.Foundation construction quality was ensured by concrete anti-freezing,thermal probe and glass steel formwork and backfill.