APP下载

不同时期止水帷幕渗漏检测方法探究

2021-09-10邹玉郭明珠

邹玉 郭明珠

【摘   要】   地下建筑的施工需要做好防渗工作,可通过两种方法判断止水帷幕是否存在渗漏通道。在浇筑混凝土早期,如果止水帷幕产生裂缝,由于混凝土温度还处于较高状态,当发生渗漏时,水会带走混凝土的大量热量,导致局部混凝土温度降低,通过温度场的异常可以准确探测出止水帷幕的渗漏通道。在混凝土水化热放热结束后,由温差产生的检测渗漏优势变弱,同一深度的止水帷幕的温度趋于一致,且与周围土壤环境的温差较小,这时可采用高密度电法检测是否发生渗漏。地下水通常天然含有钾、钠、镁、钙、氯、硫酸根和碳酸氢根7 种离子,当止水帷幕发生渗漏时,由于渗流处水的流动,电导值较未发生渗漏处低,有明显的电性差异。

【关键词】   止水帷幕;温度示踪法;高密度电法

Research on Leakage Detection Methods of Waterpro of

Curtain in Different Periods

Zou Yu, Guo Mingzhu

(Beijing University of Technology, Beijing 100124, China)

【Abstract】     The construction of underground buildings requires anti-seepage work. Two methods can be used to judge whether there is a leakage channel in the water-stop curtain. In the early stage of concrete pouring, if the water-stop curtain has cracks, because the concrete temperature is still high, when leakage occurs, the water will take away a lot of heat from the concrete, causing the local concrete temperature to decrease. The abnormal temperature field can be accurate. The leakage channel of the water-stop curtain was detected. After the concrete hydration heat is released, the advantage of detecting leakage caused by the temperature difference becomes weak. The temperature of the water stop curtain at the same depth tends to be the same, and the temperature difference with the surrounding soil environment is smaller. Groundwater usually naturally contains 7 kinds of ions: potassium, sodium, magnesium, calcium, chlorine, sulfate and bicarbonate. When the water-stop curtain leaks, due to the flow of water in the seepage, the conductivity value is lower than that of the non-leaking place. There is a significant electrical difference, at this time high-density electrical method can be used to detect whether leakage occurs.

【Key words】     water-stop curtain; temperature tracing method; high-density electrical method

〔中圖分类号〕  TU195.3    〔文献标识码〕  A              〔文章编号〕 1674 - 3229(2021)01- 0068 - 03

0     引言

随着我国城镇化水平提高,城市人口不断增长与城市内的建设用地紧张这一矛盾已经成为每个城市发展必须面对的难题。在地上建筑空间已经趋于饱和的情况下,21世纪初,地下空间的迅猛发展有效缓和了这一矛盾。而地下建筑的建设,会截断区域地下水的自然流动,地下水会流入建筑基坑中。为了减少地下水流入,避免形成地下水位降落漏斗及地面沉降等工程病害[1],必须通过建设止水帷幕阻止从基坑侧壁及基坑底流入建筑基坑中的地下水。止水帷幕在混凝土浇筑过程中,由于混凝土早……

登录APP查看全文