岩石磨蚀性和TBM滚刀磨损机理研究

Using the popular CERCHAR testing to measure the abrasiveness of rock which is CERCHAR abrasiveness index(CAI). The digital imagine processing program IPP is used to quantify the rock texture such as the grain size, the shape of grain and the index of grain homogeneity. And the rock mechanical testing machine are used to measure the strength, hardness and elastic modulus. Basic on these three experiments, this paper finds the relationship between the CAI and physical and mechanical properties of rock. They are both the mesostructure and macroscopical properties of rock. According to the theory of tribology and wear, this paper finds the disc cutter wear mechanism during the machine and rock interaction process. The detail research results are as follows: (1) The size and form of the mineral grains constituting the rocks affect the abrasiveness of the rock. The rock abrasiveness CAI is a function of the product of the texture coefficient(TC) multiplying equivalent quarts content(Q%). (2) There is no obvious relationship between the rock abrasiveness CAI and the single macroscopical property of rock such as hardness, unconfined compressive strength, tensile strength and elastic modulus. But when taking the texture coefficient(TC) and the mineral composition in consideration, it shows that the rock abrasiveness CAI is relative to the combination of the rock mechanical property, the texture coefficient(TC) and the mineral composition. That is to say various factors which are from the mesostructure feature to the macroscopical property of rock control the rock abrasiveness. (3) The disc cutter penetrating into rock is a machine/rock interaction process. During this interaction, the wear of disc cutter is mainly coming from the abrasive of abrasiveness matters. First, the surface of the cutter ring is hunched, and then the material of the cutter ring is being wiped off during the iterative interaction. Second, the hard mineral in the rock and the muck will microcosmic cutting the surface material of cutter ring. (4) The disc cutters consumption is determined by the machine parameters and the geology condition. The machine parameters include the thrust and the revolution rate of the cutterhead. The geology condition include two aspects: the macroscopical properties which are the strength and/or hardness of rock, the presence of discontinuities in rock mass, the hardness, sharp, edge and size of the muck and so on. And the mesostructure features which are the hard mineral composition, the sharp and size of the grain of the rock.

中国东部上第三系硬粘土的工程地质特性及边坡开挖工程环境效应研究

The engineering geological properties of Neogene hard clays and related engineering problems are frontiers in the fields of Engineering Geology, Soil Mechanics and Rock Mechanics. Recently, it has been recognized that Neogene hard clay is the intermediate type of material between the soil and the rock. Many aspects of them, such as sampling, testing, calculating and engineering process, are special, which could not be researched by means of theories and methods of traditional Soil Mechanics of Rock Mechanics. In order to get real knowledge and instruct the engineering practice, intersect studying of multiple disciplines, including Engineering Geology, Soil Mechanics and Rock Mechanics, etc., is necessary. Neogene hard clay is one of the important study objects of regional problem rocks & soils in our country, which extensively distributed in China, especially in Eastern China. Taking the related areas along the middle line of the Project of Transferring Water from the South to the North (e.g. Nanyang basin, Fangcheng-Baofeng area and Handan-Yongnian area), South-west of Shandong, Xu-Huai area and Beijing area, etc. as main study areas, the paper divided Neogene hard clays into reduction environment dominated origin and oxidation environment dominated origin, which distributed on areas western and eastern to Mount Taihangshan respectively. Intermediate types are also existed in some areas, which mainly distribute near the edges of depositional basins; they are usually of transitions between diluvial and lacustrine deposits. As to Neogene hard clays from Eastern China, the clay particle content is high, and montmorillonite or illite/montmorillonite turbostratic mineral is the dominating clay mineral. The content of effective montmorillonite is very high in each area, which is the basis for the undesirable engineering properties of Neogene hard clays. For hard clays from the same area, the content of effective montmorillonite in gray-greenish hard clay is much higher than that in purple-brownish or brown-yellowish hard clay, which is the reason why the gray-greenish hard clay usually has outstanding expansive property. On the other hand, purple-brownish or brown-yellowish hard clay has relatively less montmorillonite, so its property is better. All of these prove that the composition (clay mineral) of Neogene hard clay is the control factor for the engineering properties. Neogene hard clays have obvious properties such as fissured, overconsolidated and expansive, which are the main reasons that many engineering problems and geological harzards usually occur in Neogene hard clays. The paper systematically elaborates the engineering properties of Neogene hard clays from Eastern China, analyses the relationships between engineering properties and basic indexes. The author introduces the ANN method into the prediction of engineering property indexes of hard clays, which provides a new way for quantitatively assessment and prediction of engineering property indexes. During investigation in the field, the author found that there exists obvious seam-sheared zone between different hard clays in Miocene Xiacaowan formation in Xu-Huai area. Similar phenomenon also exists near the borderline between Neogene hard clays and underlying coal measures in the Southwest of Shandong province, which could be observed in the cores. The discovery of seam-sheard zone has important theoretical and practical significance for engineering stability analysis and revealing the origin of fissures in Neogene hard clays. The macrostructure, medium structure and microstructure together control the engineering properties of hard clays. The author analyses and summarizes the structural effects on hard clays in detail. The complex of the strength property of hard clays is mostly related to the characteristics of fissures, which is one of the main factors that affect the choice of shear strength parameters. So structure-control theory must be inseparably combined with composition-control theory during the engineering geological and rock/soil mechanics research of hard clays. The engineering properties, such as fissured, overconsolidated and expansive, control the instability of engineering behaviors of Neogene hard clays under the condition of excavation, i.e. very sensitive to the change of existence environment. Based on test data analysis, the author elaborates the effects of engineering environment change on the engineering properties. Taking Nanyang basin as example, the author utilizes FEM to study the effects of various factors on stability of cutting canal slopes, than sets forth the characteristics, development laws and formation mechanism of the deformation and failure of hard clay canal slopes, summarizes the protection and reinforcement principles, as well as the protection and remedy steps. On the basis of comparison of engineering properties of domestic and foreign Neogene muddy deposits, in the view of whole globe and associated with the geological characteristics of China, the paper demonstrates that the intermediate type of the material between the soil and the rock, named "hard clay/soft rock", which can not be separated abruptly, really exists in China. The author has given a preliminary classification based on its geological origin and distribution law, which is very significant for promoting the mixture of Engineering Geology, Soil Mechanics and Rock Mechanics. In the course of large scales engineering construction in China, many engineering experiences and testing data are gained, summarizing these testing results and automatically managing them with computer technology are very necessary. The author develops a software named "Hard Clay-Soft Rock Engineering Geological Information Management and Analysis System (HRGIMS)", realizes the automatic and visual management of geo-engineering information, on the basis of information management, the functions of test data analysis and engineering property prediction are strengthened. This system has well merits for practice and popularization.

阿尔金蛇绿混杂带构造岩石组合及其大地构造意义

The Alytn fault is a huge left-slip fault zone within the Asian continent, and locates such zone that is linked to main tectonic units in the western China, which makes it is very important to the tectonic framework and ore distribution in the western China. Selecting two ophiolite zones (namely Hongliugou-Lapeiquan ophiolite zone and Sulamutage ophiolite zone) respectively located within the southern and northern part of the Altyn fault and based on analysis of field geology characteristics and geochemistry, this paper recognized the rock types (mainly mafic and ultramafic rocks) within the melanges and subdivided each lithological unit based on tectonic environment. At last, this paper rebuilt the paleo-tectonic framework in the Alytn region by the method of tectonic facies and discussed its tectonic evolution with the theory of collision orogens. Combining former results with hard field observation and geochemical analysis, this paper acquired such recognitions to two ophiolte zones within the Altyn fault zone as follows: To the typical regions (Hongliugou, Lapeiquan, Mangya and Sulamutage) within the two ophiolte zones in the Altyn fault zone, this paper offered the field geology profiles. Field geology characteristics show that they are composed of melange bases (mainly abyssal flysch and carbonate rocks) and melange blocks from various tectonic environments, often with fault contact among each lithological units, belonging to typical ophiolitic melange zone. The ultramafic rocks outcropped at the Altyn region are all harzburgites. Remant grains of primary minerals have melted residual texture and elastic deformation texture under high temperature and pressure. The whole-rock analyses show their low TiO_2 contents (0.01～0.04%), low Al, Ca and high MgO contents and wide Mg~# range (89.35～95.57). Rare earth patterns have two types, namely tabacco pipe-shped and LREE-shaped, of which the former is often seen. The chondrite-nomalized Yb values of these analyses are all lower than 1. The spinels have low Ti and high Cr content and most spinels have Cr# higher than 60. All of the above characteristics show that the ultramafic rocks in the Altyn fault zone are components of metmorphic peridotites of ophiolite from depleted mantle source and most ophiolites from this zone belong to supra-subduction zone (SSZ) type ophiolite with a few mid-ocean ridge basalt (MORB) type. Geochemical analyses show that the melange blocks within the Altyn ophiolitic melange zone have different characteristics from various tectonic environments. This paper recognized such tectonic-lithological assemblages as mid-ocean basalts, oceanic island basalts, oceanic island arc tholeiites, island arc calalkaline basalts and island arc granites and inferred that these tectonic-lithological units respectively belongs to such tectonic units as ophiolites, oceanic islands and/or oceanic seamounts, oceanic island arc and a~creting arcs, which show these blocks from oceanic crust and subduction zone for the most part. For the Altyn ophiolites, the chronological data show they become new from the north to the south. Combined with the study on late slip of Altyn fault and North Qilianshan orogeny, the author inferred that the Altyn region had belonged to one part of the North Qilianshan accreting wedge-arc orogeny at paleozoic, and later huge left-slip made it locate modem site.

Effects of High Dissolved Inorganic and Organic Carbon Availability on the Physiology of the Hard Coral Acropora millepora from the Great Barrier Reef

Coral reefs are facing major global and local threats due to climate change-induced increases in dissolved inorganic carbon (DIC) and because of land-derived increases in organic and inorganic nutrients. Recent research revealed that high availability of labile dissolved organic carbon (DOC) negatively affects scleractinian corals. Studies on the interplay of these factors, however, are lacking, but urgently needed to understand coral reef functioning under present and near future conditions. This experimental study investigated the individual and combined effects of ambient and high DIC (pCO2 403 μatm/ pHTotal 8.2 and 996 μatm/pHTotal 7.8) and DOC (added as Glucose 0 and 294 μmol L-1, background DOC concentration of 83 μmol L-1) availability on the physiology (net and gross photosynthesis, respiration, dark and light calcification, and growth) of the scleractinian coral Acropora millepora (Ehrenberg, 1834) from the Great Barrier Reef over a 16 day interval. High DIC availability did not affect photosynthesis, respiration and light calcification, but significantly reduced dark calcification and growth by 50 and 23%, respectively. High DOC availability reduced net and gross photosynthesis by 51% and 39%, respectively, but did not affect respiration. DOC addition did not influence calcification, but significantly increased growth by 42%. Combination of high DIC and high DOC availability did not affect photosynthesis, light calcification, respiration or growth, but significantly decreased dark calcification when compared to both controls and DIC treatments. On the ecosystem level, high DIC concentrations may lead to reduced accretion and growth of reefs dominated by Acropora that under elevated DOC concentrations will likely exhibit reduced primary production rates, ultimately leading to loss of hard substrate and reef erosion. It is therefore important to consider the potential impacts of elevated DOC and DIC simultaneously to assess real world scenarios, as multiple rather than single factors influence key physiological processes in coral reefs.

Determining Acceptance Possibility for a Quantum Computation is Hard for PH

It is shown that determining whether a quantum computation has a non-zero probability of accepting is at least as hard as the polynomial time hierarchy. This hardness result also applies to determining in general whether a given quantum basis state appears with nonzero amplitude in a superposition, or whether a given quantum bit has positive expectation value at the end of a quantum computation.

Determining Acceptance Possibility for a Quantum Computation is Hard for the Polynomial Hierarchy

It is shown that determining whether a quantum computation has a non-zero probability of accepting is at least as hard as the polynomial time hierarchy. This hardness result also applies to determining in general whether a given quantum basis state appears with nonzero amplitude in a superposition, or whether a given quantum bit has positive expectation value at the end of a quantum computation. This result is achieved by showing that the complexity class NQP of Adleman, Demarrais, and Huang, a quantum analog of NP, is equal to the counting class coC=P.