岩土力学
巖土力學
암토역학
Rock and Soil Mechanics
2015年
11期
3101-3110,3228
,共11页
结构性土%移动正常固结线%本构模型%结构性衰减%UH模型
結構性土%移動正常固結線%本構模型%結構性衰減%UH模型
결구성토%이동정상고결선%본구모형%결구성쇠감%UH모형
structured soil%moving normal consolidation line%constitutive model%structural decay%UH model
在描述重塑土的统一硬化模型(UH模型)基础上,以动态地移动正常固结线(MNCL)代替静态的正常固结线(NCL)作为参考线来确定参考应力,将土的结构性衰减体现在MNCL的演化中,从而把UH模型扩展为可考虑土结构性的结构性土UH模型。结构性土UH模型可以合理地并连续光滑地描述结构性土的等向压缩规律、应变硬化、应变软化、剪切体积收缩、剪切体积膨胀、不排水剪切减压软化以及结构性和密度耦合影响等力学特性。相比于UH模型,结构性土UH模型新增3个参数,分别用于描述结构性的程度、衰减速度、以及塑性流动规律。通过3种天然土的试验结果与模型预测对比验证了结构性土UH 模型的合理性。
在描述重塑土的統一硬化模型(UH模型)基礎上,以動態地移動正常固結線(MNCL)代替靜態的正常固結線(NCL)作為參攷線來確定參攷應力,將土的結構性衰減體現在MNCL的縯化中,從而把UH模型擴展為可攷慮土結構性的結構性土UH模型。結構性土UH模型可以閤理地併連續光滑地描述結構性土的等嚮壓縮規律、應變硬化、應變軟化、剪切體積收縮、剪切體積膨脹、不排水剪切減壓軟化以及結構性和密度耦閤影響等力學特性。相比于UH模型,結構性土UH模型新增3箇參數,分彆用于描述結構性的程度、衰減速度、以及塑性流動規律。通過3種天然土的試驗結果與模型預測對比驗證瞭結構性土UH 模型的閤理性。
재묘술중소토적통일경화모형(UH모형)기출상,이동태지이동정상고결선(MNCL)대체정태적정상고결선(NCL)작위삼고선래학정삼고응력,장토적결구성쇠감체현재MNCL적연화중,종이파UH모형확전위가고필토결구성적결구성토UH모형。결구성토UH모형가이합리지병련속광활지묘술결구성토적등향압축규률、응변경화、응변연화、전절체적수축、전절체적팽창、불배수전절감압연화이급결구성화밀도우합영향등역학특성。상비우UH모형,결구성토UH모형신증3개삼수,분별용우묘술결구성적정도、쇠감속도、이급소성류동규률。통과3충천연토적시험결과여모형예측대비험증료결구성토UH 모형적합이성。
Based on the unified hardening (UH) model of reconstituted soil, a UH constitutive model is developed for structured clay. In this model, the dynamically moving normal consolidation line (MNCL) instead of the static normal consolidation line(NCL) is used as the reference line in determining the reference stress;and a proper increment evolution equation is proposed for the MNCL to describe the soil structural decay. The proposed structured soil UH model can reasonably simulate many behaviors of the structured soil, including the isotropic compression, strain hardening, strain softening, shear-induced shrinkage, shear-induced expansion, undrained shear decompression softening and coupling effect between soil structure and soil density. Compared to the original UH model, the structured soil UH model includes 3 new model parameters, which reflect the soil structure degree, the structure decay rate and the plastic flow rule, respectively. Comparisons between the test results and the model predictions of the three natural soils indicate that the structured soil UH model can reasonably describe the main features of the behavior of the structured soil.