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高含水率疏浚泥在外加荷载作用下通常产生大应变固结变形,不适用于传统的Barron轴对称小应变固结理论。为此,基于Gibson一维大应变固结理论和Hansbo径向固结理论,摒弃小应变假定,考虑高含水率疏浚泥的材料和几何非线性、径竖向渗流等因素,建立了等应变条件下以孔隙比为变量的轴对称大应变固结模型ALSC,Gibson、Hansbo、Kjellman等建立的固结方程是该模型的特例。基于有限差分法,编制了计算程序,进行了ALSC模型与小应变模型的数值模拟,验证了ALSC的有效性。研究结果表明:土体变形较小时,ALSC模型与Barron模型计算的固结度和超静孔压数值基本吻合;土体变形较大时,ALSC模型与“Barron+Terzaghi”理论计算的最终沉降量和固结速率取决于土体的固结参数;当C_c/C_k=1时,ALSC模型的最终沉降量小于“Barron+Terzaghi”理论,但二者固结速率相当;当压缩系数av保持不变,ALSC模型(C_k=1)与“Barron+Terzaghi”相比,最终沉降量大,固结速率慢。
Dredging mud with high water content usually produces large strain consolidation deformation under applied load, which is not suitable for the traditional Barron axisymmetric strain consolidation theory. Therefore, based on Gibson one-dimensional theory of large strain consolidation and Hansbo radial consolidation theory, the small strain assumption is discarded and the equivalent strain conditions are established considering the material, geometrical nonlinearity and vertical flow of dredged mud with high water cut. The consolidation equations established by ALSC, Gibson, Hansbo and Kjellman are the special cases of this model. Based on the finite difference method, a calculation program was compiled and the numerical simulation of ALSC model and small strain model was carried out to verify the effectiveness of ALSC. The results show that when the soil deformation is small, the values of the consolidation degree and excess pore water pressure calculated by the ALSC model and the Barron model agree well with each other. When the soil deformation is large, the final value of the ALSC model and the theoretical calculation of “Barron + Terzaghi” When C_c / C_k = 1, the final settlement of ALSC model is less than “Barron + Terzaghi” theory, but the consolidation rate of the two is equivalent; when the compressibility av remains the same, the final settlement is large and the consolidation rate is slower than the “Barron + Terzaghi” for the ALSC model (C_k = 1).