主应力

This paper describes the experimental results of the Tangshan earthquake which are in reasonable agreement with the seismological and geological data of the Tangshan districtt 1,Isopach and isochromatic fringe patterns of the Tangshen structures show three areas of strees c...

唐山等和线和等差线条纹图显示出三个应力集区，与唐山的主震和余震位置一致。2。唐山主应力轨迹线方向为东北方向。这个方向与华北现代构造应力场主压应力方向一致。激光全息光弹实验方法可以用来探讨不同的构造形态在不同边界条件下的应力分布和变化，从而为较大地震预报提供线索。

A new cyclic constitutive model for sands which can describe the deformation behavior of sands under combined variation of principal stress axes and magnitudes was developed based on the above physical fundamentals. And its effectiveness under the complex stress paths including cyclic rotation of principal stress axes is verified by a good comparison of model simulation with test results for sands.

2基于对应力主轴循环旋转条件下砂土的基本变形规律的认识，吸收和借鉴已有弹塑性本构模型研究成果中的合理概念和建模方法，建立了一个可合理描述应力主轴循环旋转效应及主应力幅值大小与应力主轴方向循环耦变效应的砂土弹塑性本构模型，并对该模型在包含应力主轴旋转的复杂循环应力路径下的有效性进行了验证。

The soil static and dynamic universal triaxial and torsional shear apparatus which can simulate the cyclic stress characteristic of sand on seabed is used to perform experimental tests of loose carbonate sand s with a relative density of 30% subjected to vertical-and-torsional coupling cyclic shear with the rotation of principal stress axes induced by ocean wave.

利用土工静力-动力液压三轴-扭剪多功能剪切仪模拟海洋波浪的加载形式，对相对密度为30%的钙质砂进行了扭转和竖向耦合循环剪切试验，着重研究了复杂应力状态下初始主应力方向角α0和中主应力系数b对钙质砂动强度特性的影响。

The main achievements could be summarized as follows.1. The basic stress-strain characteristics and related physical mechanisms for sands under cyclic rotation of principal stress axes were investigated based on three kinds of drained tests including fixed principal stress axes, cyclic rotation of principal stress axes with magnitudes of principal stresses kept constant, and cyclic changes of principal stresses in both their axes and magnitudes. The main deformation behavior of sands with inherent anisotropy under cyclic rotation of principal stress axes with magnitudes of principal stresses kept constant was obtained in the following.

本文从试验研究、规律分析、数学建模和工程应用四个方面，对应力主轴循环旋转条件下砂土的变形特性进行了较为深入的研究，取得了如下主要研究成果：(1)基于对饱和砂土进行的主轴固定单调剪切、纯应力主轴循环旋转以及主应力幅值与应力主轴耦合循环变化的三类完全排水试验成果，分析和揭示了应力主轴循环旋转条件下砂土的基本变形规律，并探讨了其受力变形的内在机理。

Triaxial stress presents minimum horizontal principal stress increasing and maximum horizontal principal stress being a "bottleneck".

三轴应力表现为最小水平主应力增加和最大水平主应力减小的"瓶颈"现象。

On the basis of the achieved result and the effect of stress such as minor principal stress, intermediate principal stress, hydrostatic pressure, stress Lode degree, a generalized hyperbolic failure function adapted naturally with the envelope form of Mohr-Coulomb criterion is proposed for brittle rocks; and a smooth failure function acquired by Yu Maohong is also presented. Thus, a generalized polyaxial strain energy strength criterion is created.

在分析脆性岩石强度的静水压力、中间主应力、最小主应力以及应力Lode角等4种效应的基础上，提出子午面上与Mohr-Coulomb准则包络线自然衔接的广义双曲线型破坏函数及八面体偏平面上光滑角隅型破坏函数，从而建立非线性广义多轴应变能强度准则。

This is discrepant with traditional point of view, which states that minimum principle stress is horizontal and perpendicular to the strike of normal fault or is vertical for reversed fault.

这与传统观点所认为的最小主应力方向垂直于断层走向或最小主应力为垂直应力相矛盾。

And the results indicate that the principal stress directions in study area are mainly NE-SW, and the second substage tectonic twist made the direction deflect from North to East, but the primary direction changed little; tectonic activities during the O〓～S～D stage is some violent, most of the area are under high stresses status, and rock fracture degree is correspondingly higher, as coinciding with the drill cores observation, i.

通过数值分析，模拟了塔中Ⅰ号断裂带和塔中45井三维模拟区O〓灰岩的构造应力场和应变场，结果表明：研究区主应力方向为北东～南西向，第二期的构造扭动使其由北向东发生了一定的偏转，但总的方位变化不大；O〓～S～D时期，塔中地区构造运动较强，研究区大部分处于高应力状态，岩石破裂程度较高，而岩芯观察结果也证实了这一结果，即O〓灰岩地层中早期形成的构造结构面比较发育，单个结构面的规模也较大；C～P时期，岩石的破坏程度较早期有所提高，主要表现在两个方面，一是各局部区岩石的破坏程度普遍有所提高；二是各个级别破裂区的分布范围相应地扩大了；研究区应力分布表现出明显的不均匀性，特别是剪应力，无论是O〓～S～D时期，还是C～P时期，都有很大的差异性，特别是在小断层的端部，剪应力比较集中，而且在断层的两盘，剪应力方向和大小都变化极快。

The nods and element meshes were signed out according to the geometry of every section. The geometric data was input computer and the element mesh body of cats＇ head was established in vizi CAD system. The Maximum stress,Minimum stress and yon Mises stress were calculated by Super SAP (93ed) finite elemental software when the force was loaded on right or left side of model in zero section.

方法猫头颅CT断层确定各层面节点并数字化，在有限元专用vizi CAD系统建立猫头颅三维有限元网格体模型，应用Super SAP有限元软件(93版)分析猫头半约束非撞击致伤时颅脑最大主应力、最小主应力、von Mises应力值及其在各层面的分布。

We can acquire the locutions of points with the same principle stress direction and the principle stress difference through the photoelastic experiments These data are the important parameters in photoelastic stress analysis.

我们可以透过光弹实验得到具相同主应力方向点的轨迹，与相同主应力差值点之轨迹，此两组数据为光弹应力分析中之重要参数。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。