基于源函数法的油层部分射开顶底封闭各向异性的三重介质油藏不稳定渗流

为解决油层部分射开、顶底封闭、各向异性的三重介质油藏不稳定渗流问题,采用点源、线源的思想,得到无限大三维油藏中的连续点源解;使用镜像反映法及Poisson求和公式,得到顶底封闭时的连续点源解,沿射开层段积分,得到油藏不稳定渗流的均匀流线源解;根据有效平均压力点理论,得到无限导流线源解;利用Stehfest数值反演和程序设计绘制典型曲线,并根据渗流机理,分析影响曲线形态特征的因素,如储容比、窜流系数、射开程度、垂向各向异性系数等.结果表明:该方法有助于认识此类复杂油藏的渗流机理,也可用于试井分析、油藏产能研究等,为合理开发此类油藏提供理论依据.  

Long-term settlement prediction of high-speed railway bridge pile foundation

The process and characteristics of loading on high-speed railway bridge pile foundation were firstly obtained by means of field research and analysis, and the corresponding loading function was presented. One-dimensional consolidation equation of elastic multilayered soils was then established with single drainage or double drainages under multilevel loading. Moreover, the formulas for calculating effective stress and settlement were derived from the Laplace numerical inversion transform. The three-dimensional composite analysis method of bridge pile group was improved, where the actual load conditions of pile foundation could be simulated, and the consolidation characteristics of soil layers beneath pile were also taken into account. Eventually, a corresponding program named LTPGS was developed to improve the calculation efficiency. The comparison between long-term settlement obtained from the proposed method and the in-situ measurements of pile foundation was illustrated, and a close agreement is obtained. The error between computed and measured results is less than 1 mm, and it gradually reduces with time. It is shown that the proposed method can effectively simulate the long-term settlement of pile foundation and program LTPGS can provide a reliable estimation.  

双层地基位移和应力场求解

通过对半无限弹性体的通解进行Ｈａｎｋｅｌ数值逆变换，得到两层地基内部受有轴对称荷载下的位移和应力解，通过改变参数进行了大量的数值计算，表明数值计算结果与文献中的研究结果一致。上述研究结果可用于设立于层状地基的桩基沉降计算。  

坝区岩体的剪切蠕变经验方程及参数数值反演

岩体的剪切蠕变特性是影响坝区边坡岩体变形与长期稳定性的重要因素之一。利用现场剪切蠕变试验数据回归拟合得到了坝区"硬、脆、碎"辉绿岩脉的剪切蠕变经验方程,并由最小二乘法得到了剪切蠕变经验方程的拟合参数;提出了可以真实模拟现场剪切蠕变试验过程以及岩体实际地层分布情况的蠕变参数数值反演分析方法。通过对比分析可知,回归拟合变形值及数值反演计算变形值均与试验变形值比较接近,最大误差均未超过8%,表明剪切蠕变经验方程能有效反映坝区岩体的剪切蠕变变形特性,且建立的剪切蠕变数值模型也是合理可靠的,这为深入认识和了解坝区辉绿岩脉在不同应力水平下的剪切蠕变力学特性提供了重要的试验和理论依据,也为坝基边坡工程稳定性分析和设计提供了技术参数保证。