高浓度浆液具有环保、节能、减排、安全、高效等特点，正逐步被认可与应用，其注入到采空区后通常形成支撑圆台，不同堆积角度圆台对上覆岩层的支撑效果不同，掌握堆积角度对圆台承载力影响规律至关重要。为研究堆积角度对圆台承载力的影响规律，利用3D打印技术进行模具制作。选取水泥为胶结材料，标准砂为骨料，胶结料和骨料质量比为1∶3，水和水泥质量比为0.56的高浓度浆液。将高浓度浆液浇筑到模具中，制作不同堆积角度圆台试样。高浓度浆液在模具中静置1 d后脱模，随后将试样放在水中进行养护，待龄期为7 d时，利用WAW-300微机控制电液伺服万能试验机，进行单轴抗压试验。结果表明：圆台直径和高度相同时，堆积角越小，极限承载能力越强。堆积角30°、45°和60°的受力-变形曲线上升阶段与经典受压应力-应变曲线一致，破坏过程均可分为Ⅰ短暂弹性阶段、Ⅱ裂隙扩展阶段、Ⅲ维护结构失效阶段。不同堆积角圆台试样受压破坏过程相似，由于周围材料对受力核心区起到了提供围压的作用，使得堆积角越小，围压越大，圆台试样越不易被破坏。随着堆积角度的增大，试样单位体积承载力增大。不考虑墩柱的排布设计，只考虑其承载力算数和时，同一注浆量下，堆积角越大，承载效果越好。

High-concentration slurry has the characteristics of environmental protection, energy saving, emission reduction, safety, and high efficiency. It is gradually being recognized and applied. After being injected into the gob, the supporting truncated cone is usually formed. Different stacking angles have different supporting effects on overlying strata.And it is important to grasp the influence of the stacking angle on the bearing capacity of the truncated cone. In order to study the effect of the stacking angle on the bearing capacity of the truncated cone,3D printing technology was used to make the mold. The cement was selected as the cementing material, standard sand as the aggregate, and the high-concentration slurry with the mass ratio of the cement and the aggregate of 1∶3, and the mass ratio of the water to the cement of 0.56 was prepared. The high-concentration slurry was poured into the mold to prepare truncated cone samples of different stacking angles. The high-concentration slurry was released after being allowed to stand in the mold for 1 day, and then the samples were placed in water for curing. When the 7 days was reached, the uniaxial compression test was carried out by a WAW-300 microcomputer controlled electro-hydraulic servo universal testing machine.The test results show that when the diameter and height of the circular truncated cone are the same, the smaller the stacking angle, the stronger the ultimate bearing capacity. The ascending phases of the force-deformation curves with accumulation angles of 30°, 45° and 60° are consistent with the stress-strain curve during the classical compression process. The failure process can be divided into I transient elastic phase，II fracture expansion phase，III maintenance structure failure phase.The pressure failure process of the cone-shaped specimens with different stacking angles are similar. Due to the surrounding material's protection of the core area, the confining pressure is provided, so that the smaller the stacking angle, the larger the confining pressure, and the more difficult it is for the cone-shaped sample to be damaged.As the packing angle increases,  the bearing capacity per unit volume of the sample increases. Regardless of the layout design of the piers, only the arithmetic sum of bearing capacities of all piers is considered. Under the same amount of grouting, the larger the stacking angle, the better the bearing effect. 

0 引言

1 试验材料与方法

   1.1 试验材料

   1.2 试验方法

2 堆积角对充填墩柱承载力影响分析

   2.1 堆积角对极限破坏力的影响

   2.2 圆台试样破坏发展过程分析

3 应用性分析

4 结论