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1.
Riqing Xu Yin Guo Zengyong Liu 《Frontiers of Architecture and Civil Engineering in China》2008,2(2):161-165
In order to study the influence of organic matter on the mechanical properties of stabilized soil and the effect of XGL2005
on stabilizing organic soil, unconfined compressive strength tests were carried out. Test results indicated that the strength
of stabilized soil decreased in the form of a logarithmic function as the organic matter content increased. In contrast, the
strength increased in the form of a power function as the content of the stabilization agent increased. The strength of cement
stabilized organic soil was reinforced greatly by adding the stabilizer XGL2005. Based on the law obtained from the test,
a strength prediction model was established by regression analysis. The model included the influence of the curing time, the
content of the cement, the organic matter content and the stabilization agent on the strength of stabilized soil.
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Translated from Journal of Zhejiang University (Engineering Science), 2007, 41(1): 109–113 [译自: 浙江 大学学报(工学版)] 相似文献
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A review of the stabilization of tropical lowland peats 总被引:2,自引:0,他引:2
Mohamad Tarmizi Mohamad Zulkifley Tham Fatt Ng John Kuna Raj Roslan Hashim Ahmad Farid Abu Bakar S. Paramanthan Muhammad Aqeel Ashraf 《Bulletin of Engineering Geology and the Environment》2014,73(3):733-746
The Deep Mixing Method, which involves the formation of in situ stabilized peat columns, is suitable for deep peat stabilization, whereas the mass stabilization technique is used to stabilize the soil of shallow peat deposits instead of the costly and problematic removal and replacement method. The concept of soil-cement stabilization involves the addition of water to cement, resulting in a chemical process known as cement hydration. Stabilization of peat by cement, which requires a significant strength increase in the cement-stabilized peat or organic soil, is attributed largely to physicochemical reactions that include cement hydration, hardening of the resulting cement paste and interactions between soil substances and primary and secondary cementation hydration products. The factors that affect these physicochemical reactions and the interactions of peat soil-cementation products that influence peat stabilization are the amount of solid particles, the water: soil ratio, the quantity of binder, the presence of humic and/or fulvic acids, the soil pH and the amount of organic matter in the peat. With the Air Curing Technique, stabilized peat samples for unconfined compressive strength (UCS) tests were kept at a normal air temperature of 30 ± 2 °C and strengthened by gradual moisture content reduction instead of the usual water-curing technique or water submersion methods that have been common practice in past experiments involving the stabilization of peat with cement. The principle of using the Air Curing Technique to strengthen stabilized peat is that peat soil at its natural moisture content contains sufficient water (water content from 198 to 417 %) that, when mixed with cement, a curing process takes place that causes the stabilized peat soil to gradually lose its moisture content and to become drier and harder throughout the curing period. This process does not require the addition of water. 相似文献
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微生物对固化/稳定化污泥长期强度的影响研究 总被引:3,自引:0,他引:3
固化/稳定化污泥中的微生物通过降解其中的有机质获得能量,同时产生有机酸和无机酸,酸能够分解固化/稳定化处理过程中生成的水化产物,对固化/稳定化污泥的强度产生影响。针对这种问题采用生物反应器强化微生物活性,获得反映微生物活动的有机质降解动力学模型,同时建立有机质降解量同强度损失量之间的关系。通过上述模型和关系可以评价微生物活动对固化/稳定化污泥强度的影响。研究结果表明,微生物对固化/稳定化污泥强度存在一定影响,随着固化/稳定化处理水平的提高,这种影响在逐渐减小。 相似文献
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水泥加固酸污染土无侧限强度特征 总被引:1,自引:0,他引:1
污染土是利用水泥固化处理后,土体的强度得到提高。针对该项技术,采用水泥固化法处理酸污染土,通过两种试验方案,对水泥加固酸污染土的无侧限抗压强度特性进行研究。试验所用酸污染土用浓硫酸配置人工制备而成,并考虑了不同水泥掺量、不同硫酸浓度和不同龄期对水泥加固酸污染土强度的影响。试验表明:水泥固化酸污染土的强度与水泥掺量和硫酸含量有密切关系,二者共同作用决定其强度的变化。在一定硫酸浓度(2~16g/kg)条件下,伴随硫酸含量的升高,水泥掺量较低时,无侧限抗压强度整体呈明显下降的趋势;水泥掺量较高时,无侧限抗压强度呈缓慢上升的趋势。随着水泥掺量提高,土样的无侧限抗压强度达到峰值时所对应的硫酸含量也逐渐变大。 相似文献
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This paper describes the application of phosphogypsum with cement and fly ash for soil stabilization. Atterberg limits, standard Proctor compaction and unconfined compressive strength tests were carried out on cement, fly ash and phosphogypsum stabilized soil samples. Treatment with cement, fly ash and phosphogypsum generally reduces the plasticity index. The maximum dry unit weights increase as cement and phosphogypsum contents increase, but decrease as fly ash content increases. Generally optimum moisture contents of the stabilized soil samples decrease with addition of cement, fly ash and phosphogypsum. Unconfined compressive strengths of untreated soils were in all cases lower than that for treated soils. The cement content has a significantly higher influence than the fly ash content. The use of two waste by-products, phosphogypsum and fly ash may provide an inexpensive and advantageous construction product. 相似文献
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水泥固化稳定重金属污染土的工程性质试验研究 总被引:1,自引:0,他引:1
随着社会的快速发展,因工业生产以及人类活动引起的地基土重金属污染现象越来越严重。地基土受到重金属污染后,其工程性质会发生改变。固化稳定法是处理重金属污染土地基的常用方法之一。以人工制备的铅或锌重金属污染土为研究对象,通过系统的室内试验,着重研究水泥固化稳定重金属污染土的工程性质。试验结果表明,土体受到污染后,其强度降低;掺入水泥固化稳定的重金属污染土的强度随水泥掺入量以及养护龄期的增加显著增大。通过试验还发现,较低浓度重金属离子的存在可以促进水泥固化土抗剪强度的提高。 相似文献
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使用化学试剂改变土样的pH值,不同pH值的土样在等量水泥作用下,固化土抗压强度存在显著的差异。为解释上述试验现象,测定了相应固化土孔隙液中主要离子的浓度,并进行热力学计算。结果表明:在相同的水泥掺量作用下,pH值较低的土样形成的固化土孔隙液中Ca(OH)2不饱和,随土样PH值的增加,固化土孔隙液中Ca(OH)2浓度增加,水泥水化生成的胶凝性水化物的量也相应地增多,固化土抗压强度增量也随之提高;当固化土孔隙液中Ca(OH)2浓度由不饱和逐渐变为饱和后,固化土中胶凝性水化物能充分生成,固化土抗压强度达到最大值,且随土样pH值的增加固化土抗压强度基本保持恒定。 相似文献
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The behaviour of organic matter in the process of soft soil stabilization using cement 总被引:1,自引:1,他引:0
In some projects where cement is used to stabilize soft soil foundations, it is found that the organic matter influences the
stabilization effect. As a consequence, extra admixtures are added to accelerate the reactions of cement and improve the stabilization
effect. In this study, different kinds of extra admixtures were used with cement to stabilize a soft soil with a high organic
content. Direct shear and unconfined compression tests were undertaken and the mechanical indices in different conditions
obtained. The total amount and components of the organic matter in every sample were also determined. The results show that
the addition of extra admixtures improves the properties of cement-stabilized soils and that different extra admixtures play
a different role.
相似文献
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水泥—石灰土的路用性能研究 总被引:1,自引:0,他引:1
针对上海地区湿软粘土的路基条件和多雨的气候特征,提出采用水泥-石灰综合处治路基的技术措施,并对水泥-石灰土的路用性能进行了室内试验与现场测试研究,结果表明,与石灰土相比,水泥-石灰土的早期强度和模量较高,后期强度和模量增长缓慢,增幅也较小;水泥-石灰土的强度与模量均能充分满足高等级道面的设计要求,且受含水量的影响较小,因此,采用水泥-石灰土对于雨季施工和缩短工期具有重要意义。 相似文献
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This study examines the wetting–drying durability of soft clay soil stabilized with recycled Bassanite, produced from gypsum waste. Specifically, this study focuses on an investigation of the effects of the moisture conditions on the strength performance and durability of very soft clay soil stabilized with Bassanite and furnace cement mixtures during the wetting–drying cycles, referred to as weathering conditions in this study. Cylindrical stabilized soil specimens were produced and then cured for 28 days. The cured specimens were subjected to different numbers of wetting–drying cycles, and then tested for unconfined compressive strength. The results show that the compressive strength increased with an increase in the Bassanite content for the different wetting–drying cycles investigated. The increase in the Bassanite content is associated with the increase in the dry unit weight, as well as in the decrease in the moisture content of the stabilized specimens for the different wetting–drying cycles investigated. The compressive strength of the soil stabilized with the Bassanite and furnace cement mixtures gradually decreases with an increase in the number of wetting–drying cycles, and the earlier cycles are seen to have a more negative effect on durability than the later cycles. Generally, the influence of the wetting–drying cycles on changes in the strength, durability and volume of the soft clay soil stabilized with Bassanite and furnace cement mixtures is not significant. This is evidence that the use of recycled Bassanite, produced from gypsum waste to stabilize soft clay soil, achieves acceptable durability, raises the strength performance and improves the engineering properties of soft clay soil in a wet environment. In addition, the effective use of gypsum waste contributes to the development of a sustainable society by reducing the huge quantity of solid waste and establishing a sound environment. 相似文献
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含铝固化剂固化软土的试验研究 总被引:2,自引:1,他引:2
用普通硅酸盐水泥、石膏和一种含铝膨胀组分构成的复合固化剂(PC+G+Al固化剂),选取2种有代表性的试样,进行软土固化试验研究,并与单纯使用水泥(PC)和水泥-石膏(PC+G)固化剂加固软土的效果进行比较分析。研究结果表明:对2种试样,PC+G+Al固化剂加固效果优于其他2种固化剂;PC+G固化剂只对孔隙比大、含水率高的试样加固效果优于PC固化剂的加固效果。PC+G+Al和PC+G固化剂的水化物中都产生钙矾石,利用钙矾石生成的固相膨胀作用填充孔隙,而钙矾石的生成在固化土中是否产生增强效果,主要取决于钙矾石与水化硅酸钙凝胶生成过程的协调性。 相似文献
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研究了水泥稳定砖与混凝土再生集料(RBCA)混合料的无侧限抗压强度、劈裂强度与抗压回弹模量等基本物理力学性能,并开展了水泥稳定RBCA混合料的四点弯曲疲劳试验;基于Weibull分布确定了混合料的疲劳寿命预估模型,分析了RBCA掺量对混合料疲劳性能的影响.结果表明:随着RBCA掺量的增加,水泥稳定RBCA混合料的无侧限抗压强度、劈裂强度与抗压回弹模量均先增大后减小,弯拉强度也具有类似规律;相同级配与水泥剂量下,混合料的疲劳寿命随着RBCA掺量的增加而增大,且RBCA掺量较小时其混合料疲劳寿命增幅较大,后续增幅变小;加入RBCA可提高水泥稳定碎石混合料的抗疲劳性能. 相似文献
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固化土孔隙液Ca(OH)2饱和度对强度的影响 总被引:5,自引:2,他引:3
物理力学性质相同的土样掺加等量水泥制备的固化土强度通常有很大差别。通过选取几组物理力学性质相近的典型土样,掺加不同比例的水泥和Ca(OH)2制备成固化土,测定了固化土孔隙液离子浓度和固化土强度。研究表明:由于土样对Ca(OH)2的消耗,可能导致固化土孔隙液中Ca(OH)2不饱和,进而影响了水化硅酸钙的生成量;不同土样对Ca(OH)2消耗量不同,导致在掺加同量水泥时水化物的生成量不同,因此固化土强度不同。土样各种化学性质的影响因素对固化土强度的影响可归结为对孔隙液Ca(OH)2饱和度的影响。对于物理力学性质相近的土样,在满足孔隙液Ca(OH)2饱和的条件下,掺入同量水泥的固化土强度相同。 相似文献
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有机质含量对水泥土强度的影响与对策 总被引:16,自引:0,他引:16
荀勇 《四川建筑科学研究》2000,26(3):58-60
通过两种不同有机质含量的软土,采用水泥和磷石膏、粉煤灰固化剂加固土强度对比试验,讨论了有机质、水泥、磷石膏、粉煤灰对加固土强度影响机理,提出了抵抗明机质含量对水泥土强度影响的措施。 相似文献