加载条件下原水管道受力特征模型试验研究

为研究堆载大小对原水管道受力变形的影响，采用量纲分析法得出模型试验相似比，并根据相似比进行模型箱的设计、管道材料的选取和重塑土的配制，研究不同工况下管道的受力特征。试验结果表明:整体上管道端部应力大于管中央应力，管轴向应力大于管环向应力。在中心加载下，管端应力值较管中央处大，前者增长速度更快，而后者增长速度较慢。在偏心荷载作用下，靠近荷载的管端应力最大，而管中央应力最小；尤其在偏载6 kPa作用下，管端下表面轴向应力达到595 kPa，而管中央处仅有64 kPa，管端受边界约束作用明显，管道呈弯曲变形。

Experimental study on stress characteristics model of raw water pipeline under loading conditions

The model test is used to study the effect of the different value of the applied loading on the stress and deformation of raw water pipeline, and the dimensionality analysis method is used to obtain the similarity ratio of model test. Then the design of the model box, the selection of pipeline material and the preparation of remolded soil are carried out according to the similarity ratio, and the stress characteristics of pipeline under different working conditions are studied. The test results show that the overall stress at the end of the pipe is greater than the stress at the center of the pipe, and the axial stress of the pipe is greater than circumferential stress of the pipe. For the case of center loading, the stress value at the end of the pipe is larger than that at the center of the pipe, while the stress growth rate at the center of the pipe is slower than that at the end of the pipe. For another case of eccentric load, the stress at the end of the pipe near the load is the largest, while the stress at the center of the pipe is the smallest. It is needed to point that the eccentric load of 6 kPa is applied, the axial stress on the lower surface of the pipe reaches 595 kPa, while it is only 64 kPa at the center of the pipe. The reason is that the end of the pipe is obviously constrained by the boundary, and the pipe is bend and deformed.