基于圆形弹性薄板模型求解扁铲侧胀试验侧向基床系数

Solution of Lateral Subgrade Coefficient in Flat Dilatometer Test Based on Model of Elastic Thin Circular Plate

扁铲侧胀试验是一种便捷、准确的原位测试方法,在仅有几种提供侧向基床系数的测试方法中,具有明显优势。对此,分析了圆形弹性薄板模型的力学微分平衡方程和边界条件,通过设定挠度曲线方程,解答出扁铲侧胀试验侧向基床系数的表达式,并考虑了基础宽度和土体类别、上覆土层压力、加载速度等因子对试验值的影响,提出了相应的修正因子,对修正公式进行了实例工程验证。

Flat dilatometer test ( DMT), as a convenient and accurate in-situ testing method, has obvious advantages among a few methods to test lateral subgrade coefficient. Herein the mechanical differential equilibrium formula and the boundary conditions of elastic thin circular plate model were analyzed and, by setting the deflection curve equation, the expression of DMT lateral subgrade coefficient was solved. Furthermore, the relevant correction factor was proposed when the effects of foundation width, soil type, overlying earth pressure and loading speed on the test values were taken into consideration. Then the correction formula was verified by engineering projects.