泥浆SAP脱水试验研究  

Experimental study of SAP dehydration of mud

作　　者：张金利[1,2] 翟浩宇 侯栋友 ZHANG Jinli;ZHAI Haoyu;HOU Dongyou(Institute of Geotechnical Engineering,Dalian University of Technology,Dalian 116024,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学岩土工程研究所,辽宁大连116024 [2]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024

出　　处：《大连理工大学学报》2023年第3期321-330,共10页Journal of Dalian University of Technology

基　　金：国家自然科学基金资助项目(重大项目51890912);中央高校基本科研业务费专项资金资助项目(DUT21LAB118)。

摘　　要：通过试验研究了高吸水性聚合物(SAP)对泥浆的脱水效果.确定了SAP在自来水、海水、泥浆中的吸水量.探讨了泥浆初始含水率、SAP消耗率及脱水次数等因素对泥浆脱水效果的影响.建立了SAP消耗率与泥浆含水率间的试验关系.为分析脱水后的土样强度,开展了快剪与无侧限抗压强度试验.对SAP回收利用方法进行了初步探讨.试验结果表明,SAP在自来水、海水、1倍液限泥浆、1.5倍液限泥浆中的吸水量分别为155、18、13、43 g/g,表明溶液阳离子种类与水的存在状态显著影响SAP吸水量.SAP在泥浆中吸水时,可在8~12 h达到最大吸水量,脱水效率较高.当泥浆初始含水率分别为42.3%与63.5%(对应1倍与1.5倍液限)时,经SAP板4次与11次处理后,对应SAP消耗量分别占干土质量的0.33%与0.95%,含水率均可降到约35%,SAP消耗量少,脱水效果明显.快剪与无侧限抗压强度试验结果表明,脱水后,快剪强度参数cq=11.5~12.7 kPa,φq=4.9°~5.8°,无侧限抗压强度qu=20.9~24.6 kPa,强度提高较大,与真空预压法相比,SAP脱水快,脱水效果优.SAP水凝胶在5.0%NaCl溶液浸泡30 min,后轻热干燥,可有效回收SAP.The effect of super absorbent polymer(SAP)on mud dewatering is studied through experiments.The water absorptions of SAP in tap water,seawater and mud are determined.The influences of initial water content of mud,SAP consumption rate and dehydration times on the effect of mud dehydration are discussed.The experimental relationship between SAP consumption rate and mud water content is established.The quick shear and unconfined compressive strength tests are carried out to analyze the strength characteristics of the dehydrated soil samples.The recycling and reuse of SAP are discussed.The test results show that the water absorptions of SAP in tap water,seawater,1 time the liquid limit mud and 1.5 times the liquid limit mud are 155,18,13 and 43 g/g,respectively.It can be seen that the water absorption of SAP is significantly affected by the type of cation in solution and the existence state of water.SAP dewatering mud time is so short that it can achieve water absorption balance in 8-12 h.Water absorption is more efficient.When the initial water contents of the mud are 42.3%and 63.5%(corresponding to 1 time and 1.5 times the liquid limit),the corresponding SAP consumption respectively accounts for 0.33%and 0.95%of the dry soil mass with water content decreasing to about 35%after 4 and 11 treatments of the SAP plate.SAP consumption is less and the dehydration effect is obvious.The results of quick shear and unconfined compressive strength tests show that after dehydration,the quick shear strength parameters are as follows:c q=11.5-12.7 kPa,φq=4.9°-5.8°,the unconfined compressive strength q u is 20.9-24.6 kPa,and the strength is highly improved.Compared with the vacuum preloading method,the SAP dehydration is faster and the dehydration effect is better.The SAP hydrogel is soaked in 5.0%NaCl solution for 30 min,and then dried with light heat,which can effectively recover SAP.

关 键 词：高吸水性聚合物 含水率 强度 软土加固 

分 类 号：TU472[建筑科学—结构工程]