球体位错理论的基本解

位错理论是现代地震学中计算地球内部位错源引起的地表变形的重要理论模型。诸多学者对准静态位错理论模型进行了研究,其中大量工作是在前人给出的基本解的基础上进行的。回顾了位错理论模型的基本物理方程,包括平衡方程、本构关系和泊松方程,并分别推导了无自重、不可压缩、自重可压缩的地球模型下的通解。给出的基本解可以用于进一步理解和计算一维径向分层的地震变形问题。     

多元逐步回归分析应用于固化土强度与微结构参数相关性评价

用石灰固化不同含盐量的滨海盐渍土,固化后土微结构参数发生了变化,力学强度大幅度提高。多元逐步回归分析计算结果表明二者之间存在着良好的相关关系,颗粒粒度分维、颗粒定向分维、等效直径、扁圆度和面积比是对固化土力学强度影响较为显著的5个微结构参数。借助土微结构参数与强度间的相关性计算分析,从另外一个角度验证石灰对滨海盐渍土的固土作用。     

黏性土力学强度与微结构动态环境能场内在关联分析

通过两组不同含水率的黏性土分别在快浸、慢浸、冻融、不同应力条件下的试验,讨论了黏性土力学强度特性与其微结构动态环境能场的本质关联,分析研究了黏性土微结构动态环境能场、外部环境条件变化与其内在介质环境变化之间的密切关联。结果表明,水的浸入对土的微结构特性影响至关重要,对土的抗剪强度的影响明显高于土的变形特性,偏湿土和受振动的土击数越多,对土的初始结构损伤越厉害,但土的后期结构强度有所提高。分析表明冻融对土的微结构破坏最为严重,其次是慢浸。     

三轴压缩条件下黏性土微细结构变化的试验研究

工程土体在宏观上所表现出来的非连续性、不均匀性和非确定性等复杂特性,取决于土体微细结构的非连续性和非确定性。在前人相关研究的基础上,通过微细结构观测试验,获取黏性土在受力条件下微细结构特征量的变化情况,研究黏性土在连续受力过程中结构参数变化规律,并将其与土体宏观物理力学性质相结合,从而解释和把握基于细观结构层次上的工程土体特性。     

Problems with inferring P–T–t paths in low-P granulite facies rocks

Microstructural evidence commonly is used to infer metamorphic reactions, which are used to infer pressure–temperature–time ( P–T–t ) paths. However, this approach in low- P /high- T  (LPHT) granulite facies metamorphic terranes has two main problems. (1) Microstructural evidence may be inconclusive, so that reactions cannot be inferred with confidence. In particular, relative timing of mineral growth inferred from inclusions, moulding relationships and foliation–porphyroblast relationships is commonly ambiguous or invalid. The most reliable indicators of metamorphic reactions are partial pseudomorphs and corona structures, especially if symplectic intergrowths (indicating simultaneous growth of two or more minerals) are involved. (2) Even reactions that can be inferred with confidence do not indicate unique P–T  trends, owing to P–T  slopes of reaction curves. Where successive reactions can be shown to have occurred in the same rock, a line or curve joining reaction-curve intersections gives an apparent single-event path. However, isotopic evidence is needed to prove that polymetamorphism (involving more complex paths making fortuitous intersections with the apparent single-event path) did not occur. Although these problems are well known, their importance is not always emphasized in metamorphic investigations.
The difficulties are illustrated by published work on P–T–t paths for Proterozoic LPHT granulite facies rocks of central Australia and Antarctica. Recent work in Antarctica has shown that P–T–t paths may be episodic and more complex than the simple, single-event paths commonly inferred from microstructural evidence alone.     

Inversion for negative dislocation on elastic block boundaries in the northeastern margin of Qinghai-Xizang block and prediction for strong earthquake location

Introduction According to the negative dislocation model (Matsu′ura et al, 1986), the relative motion be-tween active blocks under contemporary crustal movement is likely to be partially blocked on the boundaries. Suppose the lower ductile zone of boundary could slip freely, while due to the fric-tional resistance, etc., the upper brittle zone would restrict such kind of relative motion, so as to give rise to stress and strain accumulation. Namely, the surface displacement in the block bound-…     

模拟基坑开挖过程的试验研究

采用三轴剪切试验对基坑开挖过程中土体卸荷的应力路径进行模拟，研究了由于侧向卸荷对土体抗剪强度指标产生的影响，并从土的微观结构角度分析了产生这一现象的原因。试验结果表明，经过侧向卸荷过程土样的抗剪强度指标与常规三轴试验明显不同。     

吹填土沉积后微观结构特征定量化研究

粘性土微观结构是土体的一个重要质量特征.在外界环境条件影响下,吹填土在宏观上所表现出来的各种特性,都是其内在微观结构发生变化的外在反映.因此,微观结构对土的性质变化起着十分重要的作用.本文以连云港地区吹填土为研究对象,对其沉积后微观结构进行了定量测试,获得结构单元体的等效粒径、丰度、定向频率和定向分维数等定量化数据,并对结构单元体大小、平面形态和定向性进行了分析,该研究为吹填土工程性质的评价和改善提供了重要依据.     

Comparative study of microstructural characteristics and stored energy of mechanically activated hematite in different grinding environments

Hematite concentrate was mechanically treated using different milling machines and experimental conditions in air atmosphere. The changes in phase constitution, particles size, specific surface area, lattice parameters and X-ray amorphous phase fraction of activated hematite were determined. It was found that the agglomeration of the particles take place during extended milling with accessible pores for Nitrogen gas. The higher media surface brought about the largest specific surface area whatever milling devices used. After 9 h of grinding with higher media surface, the maximum and minimum specific surface area resulted from the grinding in the tumbling and vibratory mills, accounting for 6.83 m²/g and 18.42 m²/g, respectively. For the same grinding condition, tumbling mill produced the lowest X-ray amorphous phase. The maximum X-ray amorphous material estimated around 85% from the grinding in the planetary mill with higher media surface for 9 h of milling.