连云港徐圩新区盐渍土类型、分布特征及其对工程建设影响

通过对连云港徐圩新区土壤中盐渍土八大易溶盐盐度、类型及空间分布的分析得出,该地区盐渍土为典型的氯盐渍土,研究区50m以浅的深度范围土壤类型从上至下依次由超盐渍土—强盐渍土—中盐渍土过渡;土壤中易溶盐盐度、质量浓度、腐蚀性特征均在15m以浅的范围随深度的加深呈降低趋势;地下水中易溶盐各项指标普遍高于钻孔土壤样品,显示较强的腐蚀性。结果表明,研究区长期以盐场及海水型地下水对该地区土壤的影响较为显著。通过与工程腐蚀评价标准的比对,该区土壤中氯盐在近地表15m以浅的范围内质量浓度较高,达到对钢筋、管线的强烈腐蚀等级,在今后的沿海开发工程中需引以重视。

Types and Distributions of Saline Soil in Xuwei of Lianyungang and Its Influence on the Engineering Constructions

Analyses were made of contents of eight easily-dissolved salts, salinity, types and spatial distributions of the saline soil collected from Xuwei of Lianyungang. The re- sults indicate a typical chloride-reach saline soil in the studied area. Within 50m down into the soil, the types of the soil are basipetally hypersaline soil → high saline soil → medium saline soil. The salinity, contents of all dissolved salts and corrosibility of the soil all tend to decrease with the depth within a range shallower than 15m in the soil col- umn. The contents of all items of the dissolved salts are generally higher in the ground- water than in the soil samples from the drillhole, showing a strong corrosibility. All re- sults have indicated that the soil in the studied area has been apparently affected by salt fields and seawater-type of groundwater for a long time. By comparing with the criteria for evaluating the engineering corrosions, the higher content of chloride within the range shallower than 15m in the soil studied has reached up to a strong level of corroding the building reinforcing steel and pipelines, which should be paid more attention to the coastal engineering epnlnrntinns in the future.