福州档案馆新馆人工湖工程防水技术

介绍了福州档案馆新馆人工湖防水工程应用LAKEMAT誖膨润土防水毯的防水施工技术,阐述了人工湖基面处理、膨润土防水毯材料准备事项,以及自然放坡驳岸与室内水系的防水施工工艺、膨润土防水毯搭接与固定、斜坡管道穿透位置防水处理等重要环节。     

膨润土防水毯及其在地下防水工程中的应用

介绍了膨润土防水毯的防水原理、特性和施工工艺,并举例说明了膨润土防水毯在地下防水工程中的应用。     

膨润土防水毯在南京地铁车站施工中的应用

以南京地铁二号线一期工程向兴路站施工为例,详细介绍了膨润土防水毯的施工工艺和具体操作方法,指出了膨润土防水毯铺设施工过程中的注意事项,并阐述了膨润土防水毯的实际效果,从而为类似工程积累施工经验。     

福州海西动漫园人工搿防渗工程施工技术

摘要：介绍了LAKEMAT膨润土防水毯应用于福州海西动漫园人工湖的施工技术,对基面处理、材料性能、施工工艺、细部节点处理等重要环节进行了详细阐述,指出LAKEMAT膨润土防水毯是一种特别适用于人工湖等水工建筑的防水材料。     

膨润土防水毯在地铁SMW工法桩围护结构中的应用

通过膨润土防水毯在上海轨道交通6号线SMW工法桩围护形式下的外防全包应用案例，介绍了膨润土防水毯的施工工艺、节点处理和施工工效等技术。     

膨润土防水毯在基础底板防水工程中的应用

膨润土防水毯可广泛应用于市政、公路、水利及民用建筑中,通过首都机场三号航站楼滑行桥下基础底板防水工程,详细介绍了膨润土防水毯的施工工艺,尤其对各特殊节点部位施工进行了详述,保证了工程质量。     

膨润土防水毯在中海油大厦地下车库防水工程中的应用

介绍了钠基膨润土防水毯在中海油大厦（上海）地下车库防水工程中的应用,包括所选用的Vohex DS钠基膨润土防水毯的主要性能特点和在地下结构中的施工工艺及部分特殊部位如管道穿透部位、预留甩头、侧墙收口的处理方法。     

某高校校园水系景观工程防渗施工技术

介绍了某高校两个校园水系景观采用膨润土防水毯进行防渗处理的施工工艺,并总结了施工注意事项,指出与其他防水措施相比,大面积平坦场地的防渗处理中,膨润土防水毯在经济性、施工质量、施工速度上具有较大的优势。     

上海金地格林风范城人工湖防渗技术

详细介绍了膨润土防水毯在上海金地格林风范城人工湖防渗工程中的施工工艺。     

钠基膨润土防水毯在国贸三期地下工程中的应用

介绍了钠基膨润土防水毯在北京国贸三期地下防水工程中的施工工艺,并对工程各构造部位的防水设计方案及质量监控要点作了阐述。     

水化状态对含针刺GCL复合衬里抗剪强度的影响分析

针刺GCL和HDPE土工膜(GM)在防渗工程中应用广泛,含多层界面的复合衬里整体抗剪强度是边坡稳定性分析的关键。介绍了含针刺GCL复合衬里的大单剪试验方法,并且对比分析了针刺GCL初始状态分别为干燥和完全水化两种情况下的复合衬里抗剪强度。结果表明,复合衬里的剪切破坏不会发生在干燥针刺GCL内部界面,而GCL干燥状态下的复合衬里单剪强度未必高于GCL完全水化状态下的复合衬里单剪强度。结合含GCL复合衬里的剪切破坏机理,阐述了针刺GCL的水化状态对复合衬里抗剪强度的影响。含GCL复合衬里在不同水化状态下的界面滑移稳定性都应引起工程人员的重视。     

水化针刺GCL+GM复合衬里的单剪破坏特征

针刺GCL和HDPE土工膜(GM)广泛应用于填埋场防渗衬里,GCL的内部剪切强度和GCL/GM界面剪切强度是填埋场复合衬里边坡滑移稳定性的控制因素。通过开展不限定剪切破坏面的水化针刺GCL+GM复合衬里大单剪试验,获得了剪切过程中GCL/GM界面位移和GCL内部位移发展规律,分析了GM的糙面分别与GCL的有纺面和无纺面接触时的峰值强度,揭示了GCL+GM复合衬里的整体剪切破坏特征。试验结果表明:大单剪试验能够正确和合理地模拟GCL与GM间的相互作用,GCL+GM复合衬里中的极限破坏面不仅会随着法向应力的增加而发生转移,甚至出现GCL内部和GCL/GM界面同时成为剪切破坏面的临界状态。     

Full scale investigation of GCL damage mechanisms in small earth dam retrofit applications under earthquake loading

This paper reports results of full scale testing to further explore potential GCL damage mechanisms in earth dam retrofit applications in seismically active areas; in particular, to a) investigate whether shear displacements could reduce the magnitude of GCL panel overlap during earthquake shaking; b) explore the influence of gravel particles on GCL thickness at localised point of contact; and c) observe the consequences of an accidental exposure of an uncovered GCL to short duration rainfall in terms of moisture content and effects during subsequent compaction. The results of these experiments indicate that even under severe shaking no movements were detected at the GCL panel overlap. Whereas gravel particles were observed to locally reduce the thickness of the GCL to 2.2 mm, no plowing of the particle into the GCL occurred due to a lack of shear displacement at the interface, resulting in no localised internal erosion through the barrier. Furthermore, hydration of GCL panels during construction due to surface wetting was observed to result in a state of hydration less than its post-construction state. These results indicate that although each of the three GCL damage mechanisms cannot be ruled out to ever be relevant in practice, the performance of the GCL retrofitted earth dam tested was satisfactory under even severe Level 2 earthquake shaking, and suggests that the retrofitting of small earth dams with GCLs is a promising strategy to improve their static and seismic resistance.     

赤泥渗滤液对改性GCL防渗性能的影响

旨在评价商用土工合成材料黏土衬垫(GCL)用于阻隔赤泥渗滤液的有效性.赤泥渗滤液作用下GCL的防渗特性是评价其防污性能的关键因素.以商用改性GCL中膨润土为研究对象,通过自由膨胀试验,研究了4种赤泥渗滤液中膨润土的自由膨胀指数.以商用改性GCL为研究对象,通过改进滤失试验,研究了4种赤泥渗滤液作为渗透液作用下GCL渗透...     

Investigating factors influencing polymer elution and the mechanism controlling the chemical compatibility of GCLs containing linear polymers

A study was conducted to investigate (1) physicochemical factors that influence polymer elution from GCLs containing a blend of bentonite and linear (water-soluble) polymer (LPB GCLs) and (2) the mechanism that controls the chemical compatibility of LPB GCLs when polymer elutes. A series of hydraulic conductivity (k), free swell and viscosity tests were performed on a commercial LPB GCL using DI water, varying concentrations of NaCl and CaCl?. Comparable tests were also performed on a conventional bentonite (CB) GCL containing the same untreated bentonite and the same physical properties as the LPB GCL. The LPB GCL showed improved swelling and hydraulic performance compared to the CB GCL when permeated with salt solutions. Total organic carbon analysis of the effluents showed that polymer eluted from the LPB GCL regardless of the permeant solution. However, the rate at which polymer eluted increased as the concentration and valence of the dominant cation increased. The rate at which polymer eluted also increased with hydraulic gradient. The mass of polymer retained inside the GCL matrix did not correlate with the k of the LPB GCL. Free swell tests coupled with chemical analysis suggest that, the improved chemical compatibility of the LPB GCL was due to the ability of the polymer to scavenge cations from the solution which allows the bentonite to undergo adequate swelling during the initial hydration period. Analogous to water-prehydrated CB GCLs, the dispersed structure of the bentonite fabric and increased adsorbed water molecules attained during initial swelling controls the k of the LPB GCL when polymer elutes.     

Role of particle shape on the shear strength of sand-GCL interfaces under dry and wet conditions

Interface shear strength of geosynthetic clay liners (GCL) with the sand particles is predominantly influenced by the surface characteristics of the GCL, size and shape of the sand particles and their interaction mechanisms. This study brings out the quantitative effects of particle shape on the interaction mechanisms and shear strength of GCL-sand interfaces. Interface direct shear tests are conducted on GCL in contact with a natural sand and a manufactured sand of identical gradation, eliminating the particle size effects. Results showed that manufactured sand provides effective particle-fiber interlocking compared to river sand, due to the favorable shape of its grains. Further, the role of particle shape on the hydration of GCL is investigated through interface shear tests on GCL-sand interfaces at different water contents. Bentonite hydration is found to be less in tests with manufactured sand, leading to better interface shear strength. Grain shape parameters of sands, surface changes related to hydration and particle entrapment in GCL are quantified through image analysis on sands and tested GCL surfaces. It is observed that the manufactured sand provides higher interface shear strength and causes lesser hydration related damages to GCL, owing to its angular particles and low permeability.     

Field observation of GCL shrinkage at a site in Melbourne Australia

The findings from an investigation of GCL overlap for a GCL constructed as part of a 55 m long (3H:1V) composite side liner for a landfill cell after 18 months exposure in Melbourne Australia are reported. It is concluded that the nominated minimum overlap of 300 mm was appropriate to achieve the design intent for the particular GCL examined. It is also concluded that for the exposure to which the GCL was subjected, the particular GCL experienced 50–80 mm of shrinkage during 18 months of exposure when the geomembrane was covered by a 5 mm thick off-white geotextile protection layer.     

Heat and moisture migration in a geomembrane–GCL composite liner subjected to high temperatures and low vertical stresses

This paper presents the results of an experimental and numerical modelling of heat and moisture migration conducted on a composite liner comprised of a geomembrane (GMB) and a geosynthetic clay liner (GCL), over a compacted subgrade and subjected to prolonged elevated temperatures at low overburden stresses typical of brine storage ponds or solar evaporation ponds. Results are presented for a GMB sitting on a fully hydrated GCL. Heating the top of the composite liner caused a measurable increase in subgrade temperature to at least to 250 mm below the GCL. However, the presence of an air gap, simulating the presence of a wrinkle in the geomembrane, at the interface between the GMB and the GCL reduced the impact of the high temperatures on the subgrade temperature profile with depth. The change in temperature profile was accompanied by moisture migration from the GCL to the subgrade material. However no desiccation cracks were observed in the GCL and the bentonite was still in a gel form at the end of the time period investigated. Numerical modelling using finite element method (FEM) was performed to simulate the results obtained experimentally. It was found to predict accurately the temperature changes that have occurred in the subgrade material and moisture changes that occurred in both the GCL and subgrade materials.     

Shrinkage characteristics of heat-tacked GCL seams

The behavior of heat-tacked GCL seams under cyclic wetting and drying is examined. It is shown that the transverse shrinkage behavior of heat-tacked seams was similar to that observed in previous shrinkage tests performed on unseamed GCL. It is shown that the heat-tacked seam has strength comparable to the GCL adjacent to the seam and hence it is likely the strength of the GCL itself that will govern failure of the GCL in applications where there can be significant shrinkage. The strength of the heat-tacked seam subjected to 40 wet-dry cycles was at least as high as that of virgin heat-tacked samples, suggesting that 40 wet-dry cycles did not weaken the heat-tacked seam. After 40 cycles, the samples remained heat-tacked, suggesting the technique has promise as one method of preventing panel shrinkage for GCLs highly susceptible to shrinkage. It is noted that these tests are small-scale laboratory tests, under idealized conditions, and that the behavior in the field may differ due to more extreme conditions that may occur in the field and due to the greater amount of material between seams available to shrink and hence induce forces in the heat-tacked GCL seam.     

氨氮在土工合成黏土衬垫中的扩散行为研究

氨氮是垃圾渗滤液中最具代表性的污染物之一,但其在土工合成黏土衬垫(GCL)中的扩散行为至今尚未得到重视。开展批式吸附试验和扩散试样浸提试验测定氨氮在GCL中的吸附分配系数;进行扩散试验测定氨氮在GCL中的扩散系数;基于试验得到的吸附分配系数和扩散系数,使用数值软件POLLUTE v7.0对氨氮在GCL中的运移行为进行模拟。试验结果表明,氨氮在膨润土上的吸附分配系数为0.017L/g,在GCL中的扩散系数约为9.0×10^-11m²/s。POLLUTE v7.0的模拟结果显示,当考虑扩散存在时,氨氮将提前30 a击穿GCL。