考慮溫度影響的非關聯彈塑性飽和黏土本構模型

劉紅 陳琴梅 盧黎 肖楊 吳煥然

摘要：從不同溫度作用下的壓縮曲線和回彈曲線出發，利用等效的力學固結代替熱固結，將常規溫控三軸試驗過程中復雜的熱力學特性轉化為純力學特性，然后結合傳統的臨界狀態理論，運用非關聯流動法則，提出考慮溫度影響，適用于正常固結飽和黏土的非關聯彈塑性本構模型。模型包含6個獨立參數，各參數的物理意義明確，且可由常規的溫控三軸實驗確定。隨著溫度的增加，壓縮曲線和回彈曲線的斜率、臨界應力比和泊松比不變，先期固結應力呈指數形式變化，此外，塑性勢函數和屈服函數之間的比例因子可通過試算確定。結合高嶺土和伯克土的常規溫控三軸排水剪切試驗數據，給出了模型參數的具體確定方法，并將模擬值和試驗值進行對比，驗證了該模型的合理性。

關鍵詞：飽和黏土;壓縮曲線;回彈曲線;彈塑性模型;溫度影響

中圖分類號：TU431 文獻標志碼：A 文章編號：20966717（2020）04005307

收稿日期：20191225

基金項目：國家自然科學基金（No. 51678094）;內江師范學院科研資助項目（YLZY201907）

作者簡介：劉紅（1987 ），女，博士，主要從事土體熱力學特性試驗與理論研究，Email：cqulhong@163.com。

肖楊（通信作者），男，教授，博士生導師，Email：hhuxyanson@163.com。

Received：20191225

Foundation items：National Natural Science Foundation of China （No. 51678094）; Scientific Research Funding Project of Neijiang Normal University （YLZY201907）

Author brief：Liu Hong（1987 ）， PhD， main research interests： experiment and theory of soil thermodynamic properties， Email：cqulhong@163.com.

Xiao Yang （corresponding author）， professor， doctorial supervisor， Email： hhuxyanson@163.com.

Temperaturedependent nonassociated elasticplastic consititutive model for saturated clay

Liu Hong1， 2， Chen Qinmei1， Lu Li2， Xiao Yang2， Wu Huanran2

（1.College of Architectural Engineering， Neijiang Normal University， Neijiang 641100， Sichuan， P.R. China;2.Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education， Chongqing University， Chongqing 400045， P.R. China）

Abstract： Based on the compression and swelling curves at different temperatures， the thermal consolidation phase is substituted by a mechanical consolidation phase， which is of the same deformation. Then， the complex thermomechanical properties of soils have been translated into pure mechanical properties. Further， a new nonassociated elasticplastic consititutive model considering temperature effects is presented by using the traditional critical state theory and nonassociated flow rule. The whole model contains six independent parameters， and the physical significance of each parameter is specific and easy to be confirmed through the temperaturecontrolled triaxial compression test. In addition， with an increase in temperature， the slopes of the compression and swelling curves， the critical state stress ratio and poison ratio have no obvious changes， while the preconsolidation pressure changes exponentially. Otherwise， the trial method is used to determine the scaling factor between the plastic potential and yield equations. Finally， the method of determining each model parameter is put forward in detail on account of the drained temperaturecontrolled triaxial test for Kaolin and Bourke clays， and the new model is proved to be reasonable by comparing the simulation values and test data.

Keywords：saturated clay; compression curve; swelling curve; elasticplastic model; temperature effects