土工织物充填袋力学特性及计算理论研究

Geotextile bags (sometimes the geotextile tubes, geotextile sand-filled bags, geotextile bags) are stitched bags with geotextile, into which the mortar or slurry was pumped with high-pressure pump, finally forms a tubular or slab structure after the excess water seeping from the fabric gaps, which has many advantages and a broad application prospects. However, in the present research, the friction between the fabric and the solid or semi-solid filling material is negligible in the theoretical calculation, even the property of the tension and the tension or the friction characteristics of the interface between the geotextile and filling material is not further studied. Considering some deficiencies existing in the current studies, in this project, firstly the indoor filling test will be taken to research the filling characteristics such as height, shape and the drainage rate, and to research the tension and friction distribution through the strain of the geotextile measured with fiber optic sensors; secondly the pull-out test will be taken to research the friction properties of the interface between the geotextile and mortar with different water content, and the friction coefficient will be obtained; finally, according to the friction distribution of the geotextile bag and friction coefficient, the friction force can be introduced into existing calculating method of the fluid-filling bag theory, the method considering friction of solid-state semi-solid filling material will be proposed, providing guidance for the design and construction.

土工织物充填袋（有时也称作土工管袋，土工织物充砂袋，土工袋）是将土工织物缝合成模袋，用高压泵把砂浆或泥浆灌入模袋中，多余的水分可以从织物空隙中渗出，最后形成管状或板状结构，优点众多，应用前景广阔。然而目前国内外研究中，理论计算未考虑到土工织物与固态半固态充填料之间的摩擦力，更未对织物所受摩擦力及土工织物-填料界面摩擦特性进行深入研究。针对目前研究中存在的不足之处，本项目首先通过室内充填试验对土工织物充砂袋的充填高度、形状和排水速率等特性进行研究，并用光纤传感器测得土工织物袋产生的应变，从而研究袋体所受张力和摩擦力分布特性；然后通过拉拔试验研究不同含水量的砂浆-土工织物界面摩擦特性，得到界面摩擦系数；最后根据摩擦力分布和摩擦系数，将摩擦力引入到现有的流体填料充填袋理论计算方法中，提出考虑摩擦作用的固态半固态填料充填袋计算方法，对设计和施工提供指导。

土工织物有时又称土工布，是一种具有透水性的土工合成材料，可缝合成袋状，用高压泵把砂浆灌入模袋中，多余的水分可以从织物空隙中渗出，最后形成管状或板状结构，即为土工织物充填管袋，在国内外已有了许多成功的应用，积累了较为丰富的工程经验，但总的来说，其理论研究仍落后于工程实践。.针对目前研究中的不足之处，本项目首先提出适用于我国工程应用的低充填压力下的土工管袋充填特性计算方法，通过对计算参数的合理假设，对现有的无量纲计算方法进行改进，使之适用于充填压力较小袋体的设计施工参数的计算，运用数值积分对方程进行求解，并将计算结果绘制成图，方便参数查找；其次提出考虑土工织物透水性，提出充填过程中某一时刻土工管袋排水速度计算方法，通过时间离散进行迭代计算，从而可以计算从低充填压力状态到高充填压力状态的整个充填过程中袋体形状和力学特性参数值；然后考虑到土工织物用做土工管袋时受到一定张力作用，其透水率在张力作用下与无荷载情况下会有所不同，设计了实验装置对土工织物施加不同的张力，测定张力作用下的土工织物透水率，得出其透水率变化规律；最后通过开展室内土工管袋模型充填试验，对其形状、高度、所受张力、底部压力和排水速度进行研究，分析了各参数的变化规律。并用试验结果对所提出的理论计算方法进行验证，证明了所提出方法的正确性，可为实际应用提供一定指导。