9001cc金沙以诚为本

https://doi.org/10.1016/j.jrmge.2025.04.018

*论文版权归原作者和出书方所有，，，，本文仅为学习交流。。。。。

钙质砂的应力–应变特征受颗粒破碎（B）与初始相对密度（Dri）显著影响，，，，但现有本构模子少少同时思量二者的耦相助用。。。。。为填补这一空缺，，，，本文针对差别Dri和应力路径的钙质砂开展系列三轴试验，，，，系统研究颗粒破碎与临界状态行为。。。。。

主要发明如下：（1）当应力比（η）恒准时，，，，B随平均有用应力（p'）呈双曲线关系；；给定p'下，，，，B随η线性增大；；（2）临界状态线（CSL）随Dri增大而下移，，，，而临界状态摩擦角（φcs）随B增大而减小。。。。；；谏鲜鲂Ч，，，提出统一的颗粒破碎演化模子，，，，用以量化差别加载条件下钙质砂的破碎水平。。。。。将该模子与正常固结线（NCL）及CSL方程耦合，，，，乐成再现随B增大、NCL与CSL斜率增大的征象，，，，并定量评估B对φcs的影响。。。。。最后，，，，在临界状态土力学与亚塑性理论框架内，，，，建设了同时引入B与Dri的亚塑性模子；；该模子在差别初始相对密度、应力路径及排水条件下的模拟效果与试验数据高度吻合，，，，验证了其可靠性。。。。。

Fig. 1. Physical properties of calcareous sand: (a) SEM image; and (b) Grain size distribution (GSD) curve of calcareous sand.

Fig. 2. Test schematic and apparatus: (a) Test schematic; and (b) GDS triaxial automated system.

Fig. 3. Effect of initial densities on the triaxial test results of calcareous sand: (a-b) CTC test, p_c=200 kPa; (c-d) TC test, p_c=200 kPa; (e-f) RTC test, p_c=200 kPa; (g-h) CU test, p_c=200 kPa; (i-j) CTC test, p_c=800 kPa; (k-l) TC test, p_c=800 kPa; (m-n) RTC test, p_c=800 kPa; and (o-p) CU test, p_c=800 kPa

Fig. 4. Variation in GSD curves of calcareous sand and relationship between B with p′ and η: (a-b) Effect of D_ri; (c-d) Effect of p_c; and (e-f) Effect of loading path.

Fig. 5. Relationship between B with p' and η: (a) B- log₁₀ p' relation; and (b) Determination of ω₀ and k_ω (Solid colourful lines represent simulation results by Eq. (8))

Fig. 6. Stress ratio of calcareous sand sheared to maximum axial strain: (a) CTC test; (b) TC test; (c) RTC test; and (d) CU test.

Fig. 7. Comparison of B-p' relations with different test results: (a) Dogs Bay sand; (b) Angular granite (PL: Proportional loading); and (c) Decomposed granite.

Fig. 8. Predicted and measured NCLs of calcareous sand with various initial densities. (a) Predicted versus experimental test results; (b) Influence of k_Dr (Eq. (36)); and (c) Influence of k_B (Eq. (36)).

Fig. 9. Predicted and measured CSLs of calcareous sand with various initial densities: (a) D_ri=0.1; (b) D_ri =0.3; (c) D_ri =0.6; and (d) D_ri =0.9.

Fig. 10. Schematic of the effect of particle breakage on the location of CSL in e-log₁₀p' plane

Fig. 11. Influence of parameter χ and β on predicted results: (a) Effect of χ (Eq. (44)); and (b) Effect of β (Eq. (44)).

Fig. 12. Relationship between critical friction angle φ_cs with particle breakage B of calcareous sand: (a) Experimental data; and (b) Effect of χ_B on predicted M_cs (Eq. (48)).

Fig. 13. Influence of breakage evolution parameters on model prediction results in drained triaxial test: (a-b) Effect of ω₀; (c-d) Effect of k_ω; and (e-f) Effect of p_B.

Fig. 14. Influence of initial density effect parameters on model prediction results in drained triaxial test: (a-b) Effect of D_ri; (c-d) Effect of k_Dr; and (e-f) Effect of χ.

Fig. 15. Influence of breakage effect parameters on model prediction results in drained triaxial test: (a-b) Effect of k_B; (c-d) Effect of β; and (e-f) Effect of χB.

Fig. 16. Comparison between model predictions with CTC tests results of calcareous sand at different D_ri: (a-b) D_ri =0.1; (c-d) D_ri =0.3; (e-f) D_ri =0.6; and (g-h) D_ri =0.9.

Fig. 18. Comparison between model predictions with TC tests results of calcareous sand at different D_ri: (a-b) D_ri =0.1; (c-d) D_ri =0.3; (e-f) D_ri =0.6; and (g-h) D_ri =0.9.

Fig. 20. Comparison of the predicted and measured values of B

Fig. 21. Change in GSD of calcareous sand with D_ri=0.1:(a-b) CTC test; (c-d) TC test; (e-f) RTC test; and (g-h) CU test.

Fig. 22 Comparison between model predictions with drained triaxial tests results of Silica sand at different D_ri: (a-b) D_ri =0.30; (c-d) D_ri =0.60; and (e-f) D_ri=0.90.

现有本构模子未能充分思量颗粒破碎（B）与初始相对密度（D_ri）对钙质砂的耦合影响。。。。。为此，，，，本文开展了系列三轴压缩试验，，，，涵盖差别D_ri、应力路径与排水条件。。。。；；谑匝樾Ч，，，提出了新的破碎演化模子，，，，并修正了正常固结线（NCL）与临界状态线（CSL）方程，，，，以同时纳入B与D_ri的联相助用。。。。。随后，，，，将这些公式嵌入亚塑性框架，，，，建设了刷新的亚塑性本构模子。。。。。主要结论如下：

（1）三轴试验批注，，，，B与D_ri对强度与变形具有显著且相互依赖的影响。。。。。低围压下B较。。。。。，，，D_ri起主导作用；；随围压增大，，，，B增添，，，，D_ri的影响削弱。。。。。

（2）颗粒破碎主要受应力比η与平均有用应力p′控制。。。。。η恒准时，，，，B随p′增大而升高；；p′恒准时，，，，B与η成正比。。。。。提出的双曲线破碎演化模子仅需3个易标定参数，，，，即可形貌差别应力路径、D_ri与围压下的破碎行为。。。。。

（3）新NCL与CSL方程可准确反应随B增大而陡化、随D_ri增大而下移的纪律；；临界状态摩擦角φ_cs随B线性降低。。。。。

（4）将破碎演化模子与修正NCL、CSL方程融入亚塑性框架，，，，建设了可同时思量颗粒破碎与初始密度的扩展亚塑性模子，，，，可准确展望级配演化、强度与变形。。。。。

只管模子展望性能优异，，，，但验证仅限于等向固结与枯燥加载。。。。。现实岛礁与离岸工程常面临各向异性应力与风波循环荷载，，，，后续研究将拓展模子至这些重大工况，，，，提升其工程适用性。。。。。

备注：论文及摘要等为论文原文的中文译文，，，，仅供快速参考；；若遇语义或手艺细节歧义，，，，请以英文原文为准。。。。。完整研究内容、参数取值及验证数据请查阅原文。。。。。