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为探究土工格室加筋路堤在循环荷载及静载下的各种性能,利用美国GCTS公司的USTX-2000加载装置进行加载,通过改变加筋层数、格室高度,格室焊距对土工格室加筋路堤进行一系列模型试验。对各种工况下加筋路堤极限承载力、长期循环荷载及固定振次循环荷载后极限承载力的变化进行研究。试验表明,土工格室加筋能显著提高地基极限承载力并能显著减小坡顶和坡中临界破坏时的法向累积变形,在加筋间距一定的情况下,加筋层数增加和格室高度增大均可不同程度提高极限承载力并减小临界破坏时坡顶法向累积变形,格室焊距的减小也可在一定程度提高极限承载力,格室焊距对边坡法向变形影响不大;长期循环荷载下固定间距加筋层数对路堤竖向累积沉降量影响不大,而对边坡坡顶法向累积变形有一定影响,格室高度增大和格室焊距减小均可不同程度减小路堤竖向累积沉降量和坡面法向累积变形;越靠近加载点处,路堤土压力值受加筋影响越显著,加筋提高了土体刚度和密实度,使加筋路堤土压力值较无筋路堤明显增大;对于无筋路堤,改变动载幅值和振次均导致振后极限承载力有不同程度的降低,而对于加筋路堤,当动载幅值≥30 k Pa或动载振次≥1 000时,振后极限承载力均有不同程度的提高。
In order to explore the geocell reinforced embankment in the cyclic loading and static load under the various performance, the use of the United States GCTS company USTX-2000 loading device for loading, by changing the number of layers, cell height, cell room welding geogrid Lattice reinforced embankment for a series of model tests. The ultimate bearing capacity, long-term cyclic loading and ultimate bearing capacity of embankment under various working conditions were studied. The tests show that the geocell reinforced can significantly increase the ultimate bearing capacity of the foundation and can significantly reduce the normal cumulative deformation at the critical failure of the top and the slope. With the reinforcement spacing constant, the number of stiffened layers increases The increase of the height of the chamber can increase the ultimate bearing capacity and reduce the normal cumulative deformation of the top of the slope when the critical failure occurs. The decrease of the welding space of the lattice can also improve the ultimate bearing capacity to a certain extent. Which has little effect on the deformation. Under the long-term cyclic loading, the number of stiffened layers with fixed spacing has little effect on the vertical cumulative settlement of the embankment, but has some influence on the normal cumulative deformation of the slope roof. The height of the cell room increases and the welding space The decrease of the vertical cumulative settlement of the embankment and the normal cumulative deformation of the slope can be reduced to some extent. The closer to the loading point, the more significant the embankment earth pressure is affected by the reinforcement, and the reinforcement increases the stiffness and compaction of the soil, So that the embankment earth pressure value is significantly increased compared with the non-reinforced embankment; for the non-reinforced embankment, changing the dynamic load amplitude and vibration times lead to the ultimate bearing capacity after varying degrees of reduction, and for the reinforced embankment, when the dynamic load Amplitude ≥30 kPa or dynamic vibration ≥1 000 After the vibration ultimate bearing capacity have different degrees of improvement.