Treatment of Saline Soil with Soil Water Isolating Coagulant
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摘要: 兰州新区变电站场坪普遍存在膨胀问题,导致邻近的混凝土道路开裂,影响变电站的正常运行。在详细分析当地土壤性质的基础上,采用新型土壤隔水聚凝剂处理土体,对比空白组,测试处理后土体的吸水率、吸水膨胀率、无侧限抗压强度及软化系数。研究表明,土壤隔水聚凝剂的掺加能够显著提高土体的气干无侧限抗压强度、浸水24 h的无侧限抗压强度和软化系数,降低吸水率及吸水膨胀率,从而提高了土体的耐水性,应用于工程可有效降低水分的渗入,降低该类工程中膨胀问题的发生率。Abstract: Expansion problems occurred in many electricity substation yard site in Lanzhou, which caused severe cracking of adjacent concrete road and affectted the operation safety of the substation. A new soil water isolating coagulant (SWIC) was used to solve such problems. The water absorption, expansion in water, unconfined compressive strength, and softening coefficient of the specimen added different dosage of SWIC were tested after curing for 7 days. The results show that the addition of SWIC can significantly improve the unconfined compressive strength, whether air dried or immersed in water for 24 h. The softening coefficient which indicate the water resistance was improved, and the water absorption, water expansion were reduced. The infiltration of water and expansion problems can be effectively reduced as it was used in engineering.
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Key words:
- saline soil /
- expansion /
- soil water isolating coagulant /
- water resistance
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表 1 土样中SDS不同组分掺量
% 组分 空白组 I II III IV V VI A 0 0.06 0.08 0.06 0.08 0.06 0.08 B 0 0.80 0.80 1.10 1.10 0.80 1.10 纤维 0 0 0 0 0 0.1 0.1 表 2 可溶性Cl−、SO42−含量
序号 Cl−/(mg·kg−1) SO42−/(mg·kg−1) Cl−/% SO42−/% S-1-1(表层) 13015 27340 1.30 2.73 S-1-2(下层) 912 4592 0.09 0.46 S-2-1(表层) 2989 27880 0.30 2.79 S-2-2(下层) 204 6150 0.02 0.62 表 3 SDS各组分掺量变化对土体主要性能的影响
掺量变化
(相对于I)气干强度
/MPa浸水强度
/MPa软化系数 吸水膨
胀率/%S-1 S-2 S-1 S-2 S-1 S-2 S-1 S-2 A↑(Ⅱ) +0.31 +0.59 +0.15 +0.05 −0.06 −0.09 −0.44 −0.21 B↑(Ⅲ) +0.06 +0.34 +0.22 +0.20 +0.02 +0.01 −0.52 −0.35 A↑,B↑(Ⅳ) +0.26 +0.48 +0.62 +0.49 +0.13 +0.09 −0.95 −0.62 加纤维(Ⅴ) −0.21 +0.14 −0.21 −0.25 −0.11 −0.14 −0.6 −0.37 A↑,B↑,加
纤维(Ⅵ)−0.16 −0.01 +0.19 +0.09 +0.05 +0.02 −0.78 −0.53 注:表中“+”代表增加,“−”代表降低。 -
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