低掺量水泥固化高含水率淤泥强度影响因素试验研究

发布时间：2018-01-07 13:04

本文关键词：低掺量水泥固化高含水率淤泥强度影响因素试验研究　出处：《华中科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：采用低掺量水泥固化高含水率淤泥(简称HW-LC-clay)既能有效解决航道疏浚淤泥的弃置问题,又能为规模空前的围海垦地工程提供填料。与传统水泥固化黏土相比,用作垦地填料的HW-LC-clay具有明显的特殊性。首先,HW-LC-clay含水量高而水泥掺量低,其强度特性与传统水泥土强度特性存在一定的差异。其次,用作垦地填料的HW-LC-clay通常浇筑体积庞大,一方面水化热会引起内部养护温度明显偏高,产生一定的温度效应;另一方面较大的浇筑厚度也会使HW-LC-clay在养护过程中承受较大的养护压力,存在一定的养护压力效应。养护温度效应和压力效应的存在无疑加大了评价HW-LC-clay强度指标的难度,针对传统水泥土的相关经验公式通常不再适用。因此,有必要对HW-LC-clay的强度特性及其影响因素展开有针对性的研究。本文通过大量室内试验,测试不同配合比下HW-LC-clay的强度指标,引入归一化方法,揭示配合比参数对HW-LC-clay强度指标的影响规律;测试不同养护压力下HW-LC-clay的强度指标,分析既有评价指标应用于描述养护压力对HW-LC-clay强度影响的适用性;测试不同养护温度下HW-LC-clay强度发展过程,比较养护温度对不同水泥胶结材料强度发展的影响规律并尝试分析了其内在影响机理。基于上述工作,本文主要得到以下结论:(1)HW-LC-clay强度随含水率的增加呈非线性减小,随水泥剂量的增加呈非线性增加,含水率和水泥剂量对HW-LC-clay强度特性的影响是相互独立的两个参数;(2)养护压力对HW-LC-clay强度特性影响显著,且与养护后孔隙比(或有效孔隙比)存在一一对应的指数关系,然而采用养护后孔隙比和有效孔隙比均无法定量地描述养护压力对HW-LC-clay强度的影响;(3)养护温度对不同水泥胶结材料(混凝土、水泥固化海泥和水泥固化有机质黏土)的强度发展规律和影响机理截然不同。
[Abstract]:The problem of disposal of dredged silt in waterway can be effectively solved by using low content cement solidified and high moisture content silt (HW-LC-clay). Compared with the traditional cement solidified clay, the HW-LC-clay used as the reclamation filler has obvious particularity. First of all. The strength characteristic of HW-LC-clay is different from that of traditional cement-soil because of its high water content and low cement content. HW-LC-clay, which is used as filling material for reclamation, is usually large in volume. On the one hand, the heat of hydration will cause the internal curing temperature to be obviously higher, resulting in a certain temperature effect. On the other hand, the larger pouring thickness will also make HW-LC-clay to bear a large maintenance pressure in the process of maintenance. The existence of curing pressure effect and the existence of curing temperature effect and pressure effect undoubtedly increase the difficulty of evaluating HW-LC-clay strength index. The empirical formula of traditional cement-soil is not applicable. Therefore, it is necessary to study the strength characteristics of HW-LC-clay and its influencing factors. A large number of laboratory tests have been carried out in this paper. The strength index of HW-LC-clay under different mix ratio was tested and normalized method was introduced to reveal the influence of mix ratio parameters on HW-LC-clay strength index. The strength index of HW-LC-clay under different curing pressure was tested and the applicability of existing evaluation index to describe the influence of maintenance pressure on HW-LC-clay strength was analyzed. The development process of HW-LC-clay strength at different curing temperatures was measured. The influence of curing temperature on the strength development of different cement cementing materials is compared and the internal influence mechanism is analyzed. The main conclusions are as follows: the strength of HW-LC-clay decreases nonlinear with the increase of water content and increases with the increase of cement dosage. The effect of water content and cement dosage on the strength of HW-LC-clay is independent of each other. (2) curing pressure has a significant influence on the strength characteristics of HW-LC-clay, and has a one-to-one exponential relationship with the void ratio (or effective void ratio) after curing. However, the effect of curing pressure on HW-LC-clay strength can not be quantitatively described by using the void ratio and effective void ratio after curing. (3) the strength development and influence mechanism of curing temperature on the strength of different cement cementing materials (concrete, cement solidified sea mud and cement solidified organic clay) are very different.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU447;TU472

【相似文献】