【作者】 王档良；

【导师】 隋旺华；

【作者基本信息】 中国矿业大学 ， 地质工程， 2011， 博士

【摘要】 本文基于流体力学理论和地下水溶质运移理论,采用物理模型实验、数值模拟及现场试验等方法,研究了静水条件下浆液的扩散方式及其形成条件、注浆动态压力经验公式、多孔注浆效应,分析了在运动条件下脲醛树脂浆液凝胶特征,建立了动水条件下浆液流动的力学模型。本文的研究内容及取得的认识包括:(1)通过对脲醛树脂浆液的防渗堵漏适应性研究,得出了摩尔比小于1.5的脲醛树脂不适合作为防渗堵漏注浆材料,总结出了脲醛树脂类浆液可以作为防渗堵漏注浆材料的条件。在研究浆液凝胶机理的基础上,根据室内试验获得了脲醛树脂浆液在酸性条件下的固化特征,为提高浆液在防渗堵漏工程中材料的可靠性提供了依据。(2)基于相似理论,进行了砂土体介质中注浆压力室内模型试验,研究了注浆压力的影响因素,并根据相似准则建立了化学浆液注浆动态压力公式。该公式表明,在注浆过程中,注浆压力是动态变化的,可以通过对注浆泵流量、浆液凝胶时间参数的实时动态调整,实现压力的过程实时控制,最终达到改善岩土体的可灌注性,提高灌注效果的目的。(3)基于圆孔扩张模型力学理论和统一强度准则,分析了注浆浆液在土体中扩散的弹、塑性力学关系,得出了浆液在砂土体中发生渗透和劈裂的压力条件,并通过室内试验验证了这一规律。(4)利用VMODFLOW数值软件,研究了双孔、三孔、圈形孔布置的多孔条件下浆液流动规律,分析了注浆压力分布规律和浆液浓度扩散特征。结果表明,在双孔和三孔注浆时,在已经形成的注浆范围周围容易形成压力梯度增高带,该增高带的形成使得浆液向增高带相反方向流动,即在新注浆孔和老注浆孔之间很难形成连续的注浆固结体,所以注浆范围大小不能是简单的单孔注浆半径的叠加。而圈形布孔时,容易在未封闭的圈内形成高压带,而在圈外形成低压带,浆液更容易流向低压带。(5)凝胶时间是注浆过程控制中的重要参数。本文分析了浆液在运动状态下的凝胶时间特征,根据浆液动态凝胶特征要求设计了浆液动态凝胶测试平台,获得了在不同流速下浆液的浆液固化时的粘度变化规律。结果表明,浆液在运动状态下凝胶时间和静止状态下相比,其具有一定的滞后性。通过实验所获得的脲醛树脂浆液在运动状态下粘度变化实时曲线,建立了脲醛树脂浆液在运动状态下浆液固化时、粘度随时间和剪切速率变化的数学公式。(6)动水条件下化学注浆的力学模型和数值模拟通过室内模型试验研究了不同动水条件下动水注浆效果的影响因素。基于地下水运移模型和VMODFLOW数值模拟软件,分析了动水注浆时浆液流场与动水流场之间相互作用,运用流体力学欧拉方程,构建了动水条件下化学浆液(脲醛树脂浆液)注浆的力学模型,建立了浆液扩散随时间和空间变化公式。更多还原

【Abstract】 Based on fluids theory and underground water substance migration theory, this paper aims to study the different difussion patterns and conditions of grout under the static water, emprical formula of grouting pressure behaviour and porpous grouting effect. Furthermore, several methods including physical model experiment, numerical simulation and field test etc. are employed in this process. Besides, it is to analyze the gelation features of urea resin grout in motion and build the grout hydromechanical model under dynamic water. The research contents of this paper lies in the following aspects:1. The features of urea resin grout are analyzed on the basis of the research about anti-seepage adaptablity of the grout. The result shows that urea resin with a molar ration less than 1.5 is not suitable as the anti-seepage grouting material. The conditions of urea resin grout acting as the anti-seepage grouting material is also presented. On the basis of researching the gelation mechanism of the grout and labortary test result, it possesses the curing rules feature and water contamination feature of urea resin grout in the acid condition so as to provide the convincing reference for improving the groutability in the application of anti-seepage project.2. Based on the theory of similarity, the interior model test of grouting pressure in the grouting process is made. Having researching about the influencing factors of grouting pressure, the dynamic formula of chemical grouting is listed according to the similarity criterion. The formula shows that, according to the grouting pressure change, the groutability and its effects of gneis can be improved through adjusting grouting pumping capactity and grout gelation time and grouting pressure in the whole process of grouting.3. Based on the mechanical theory of cavity expansion model and unified strength criterion, the diffusion mechanics of the grout in soil mass is analyzed. And pressure conditions of the grout while penetrating and gadding in sandy soil is given and the rationality of this rule is verified through laboratory test.4. According to the migration rules of underground water, the grout flowing rules under porous conditions including diplopore, triporate and circle-type setting is studied and the distribution rules of grouting pressure and concentration diffussion features are analyzed by applying numercial analysis software VMODFlow4.0. The result proves that the pressure gradient rising in the grouting scope renders the rightabout flow of the grout. In other words, it is very difficult to form the continuous grouting induration between new grouting hole and old grouting hole. As a result, the grouting scope cannot be simlpe superposition of the haplopore grouting radial.5. The gelation time feature of the grout in stationary state is studied by referring to gelation time, the important parameter in the grouting process control. In the requirement of dynamic gelation features of grout, the testing platform of dynamic gelation is presented. By revolving speed instead of flow velocity, the viscosity changing rules of grout solidification at different revolving speeds are analyzed. Compared with the grout gelation time in static state, its dynamic state lies in certain hysteresis. According to the real-time viscosity change curve of gelresin grout in dynamic state, the mathematical formula of urea resin grout gelation is given. The formula indicates the rules of grout solidification viscosity as the time and shearing rate changes.6. Through laboratory test, the impact on the grouting effects under the conditions of different dynamic water is studied. On the basis of underground water migration model and numerical simulation software VMODFLOW, the rules about the interractions between the flow field of grout and that of dynamic water while grouting under dynamic water. By applying Eulerian equation of hrdromechanics, the grouting mechanical modle of chemical grout under dynamic water (urea resin grout) and the formula of grout changes over time and space and the optimal distance formula of the position of grouting holes are setup.更多还原