基于透明介质的裂隙岩体动水注浆堵水机理试验研究

The proposal is entitled "Experimental investigation on the mechanism of grouting into rock fracturs for controlling dynamic groundwater based on transparent rock mass simulation". The interaction mechanism between injected grout and rock fracture, and the propagation and gelling under dynamic groundwater conditions play a significant foundation in the development of grouting theory and technology. On the basis of the completed NSFC project "Experimental study on chemical grout injection mechanism using transparent soil" under Grant No. 41072237, the idea of transparent fractured rock mass experiment will be proposed in the present proposal and an transparent fracture grouting experimental equipment will be established. An interpretation method for grout propagation based on digital image cross correlation (DIC) displacement analysis will be proposed. The filling relationship of injected grouts and fractures will be quantitatively described and characterized by the in-situ engineering geological explorations and the 2D and 3D propagation pattern will be re-established by micro analysis. The propagation and gelling for time-dependent viscosity grout injection into a single fracture or the fracture network saturated and permeated by water will be investigated by using the transparent media experiment; the main geological and engineering factors influencing the sealing effect of fracture water inrush will also be identified. The theoretical and numerical simulation will be conducted in this research to deduce the mathematical model for grouting into a single fracture and fracture network with flowing water, and establish the criteria of grouts retention and sealing off in fractures. The experimental results will provide a scientific foundation for improving grouting design and establishing empirical grouting effect criteria. Moreover,the validation and verification of propagation and criteria will be conducted through the grouting practices.

动水环境下的注浆浆液与岩体裂隙的相互作用机理、浆液的扩散与凝固规律是注浆理论和技术发展的重要科学基础。本项目将在已经完成的国家自然科学基金项目"化学注浆扩散机理的透明土试验研究（41072237）"的基础上，提出透明裂隙岩体试验技术的理念，建立透明裂隙注浆试验装置和基于数字图像互相关(DIC)位移分析原理的浆液扩散解释方法。结合野外工程地质调查和室内微观分析，对浆液固结岩体裂隙充填关系进行定量描述和模型重构，建立浆液扩散的二维和三维模式。通过透明岩体裂隙动水注浆室内模拟试验，研究粘时变浆液动水环境下在单一裂隙和裂隙网络中扩散与凝固规律,影响动水注浆裂隙岩体涌水封堵效果的地质因素和工程因素。建立动水裂隙岩体中单裂隙和裂隙网络动水注浆的数学模型，研究裂隙岩体浆液留存和封堵效果判据。将研究获得的浆液扩散规律和封堵效果判据作为改善注浆工程设计的科学基础，并对其有效性进行工程实践验证。

动水环境下的注浆浆液与岩体裂隙的相互作用机理、浆液的扩散与凝固规律是注浆理论和技术发展的重要科学基础。在国家自然科学基金项目“化学注浆扩散机理的透明土试验研究（41072237）”的基础上，将透明土理念应用于透明裂隙岩体注浆研究，建立了透明裂隙注浆试验装置和基于数字图像互相关原理的浆液扩散解释方法。.重点研究了岩体单裂隙、二维裂隙网络、三维裂隙网络动水注浆多场耦合特性和动水注浆浆液扩散模型及堵水效果判据。研究发现：（1）平直单裂隙动水注浆堵水效果的影响因素排列依次为动水流速、裂隙开度、凝胶时间和单位灌注量。粗糙单裂隙注浆堵水效果的因素依次为粗糙度系数、裂隙开度、初始动水流速、浆液胶凝时间。粗糙度大的裂隙容易被封堵。（2）二维平直裂隙网络动水注浆封堵控制因素与单个裂隙的相同。定开度的二维粗糙裂隙网络动水注浆封堵注浆效果的因素依次为初始动水流速、裂隙粗糙度系数、注浆流量和胶凝时间。（3）根据化学浆液在三维正交裂隙网络中动水注浆的浆液扩散形态，划分为压力作用扩散/沿裂隙方向扩散、重力和顺水流双重作用扩散/近圆形扩散以及顺水流方向扩散/顺水流近圆形扩散。三维正交裂隙网络注浆的裂隙渗流压力与注浆压力呈现正相关关系，温度变化曲线与渗流压力曲线呈现负相关关系。（4）建立了考虑温度场、渗流场、应力场和不同裂隙动水注浆浆液扩散的数学模型、裂隙岩体注浆考虑动水和粘时变的封堵条件。.本项目对粘时变浆液动水环境下在岩体裂隙内的扩散凝固规律、裂隙岩体动水注浆浆液封堵和留存判据2个科学问题有了深入的认识，揭示了裂隙动水注浆浆液扩散凝固、封堵留存的本质，具有重要的科学意和实用价值。