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1.
The spatial distribution of inter-layer shear zones is studied, based on the fully mapped inter-layer shear zones at the Gaobazhou dam site on the Qingjiang River in Hubei province, China. The field observations revealed that two types of inter-layer shear zone, under-developed and well-developed, are distributed differently. The former are associated with the incompetent rock layers, and the latter are controlled by the inter-bed folds and lithological properties of the strata. To represent their lithological properties geomechanically, data on strength by the Schmidt hammer test and thickness of each field-identified rock layer were collected to form strength sequences and thickness sequences. The adjacent rock layers of similar strength are then grouped, and two grouped sequences are combined into a single sequence, whose individual term is the strength weighted by the exponential function value of the centralized thickness (SCT). The rescaled range (R/S) analysis results of SCT (SCT-R/S), taking into account the presence of inter-bed folds, are in good agreement with R/S analysis results of the spacing sequence of the well-developed inter-layer shear zones. Thus the SCT-R/S model has the potential to predict their spatial distributions. 相似文献
2.
S.A. Ola 《Engineering Geology》1991,30(3-4):325-336
A brief review of the geology of the tar sand areas of Nigeria is given. Analysis shows that the tar sand used for the tests consists of a well graded silty sand (cmf) with about 5% clay; and 3–5% bitumen. Results presented show a very high in situ compressive strength of about 450 kN/m2, a high ratio of tensile to compressive strength of about 22%, peak shear strength parameters of Cp′=15kN/m2and φp′ = 19° and residual parameters of Cr =0, φr = 18°. The compacted tar sand behaved like an overconsolidated soil with a preconsolidating pressure, Pc of 140 kN/m2. In general, the results of the in situ strength tests indicate that the Nigerian tar sand behaved as a soft sandstone. 相似文献
3.
Abstract The magnitudes of plastic strains of 104 metacherts were determined from the deformed shape of initially spherical radiolarians in the Sambagawa high- P type metamorphic belt of Western Shikoku, Japan. The strain magnitude increases with increasing metamorphic temperature from several per cent to 250%. The a2 /a3 ratio of strain ellipsoids in the higher metamorphic grades decreases with increasing metamorphic grade while the a1 /a2 ratio increases rapidly. The long axis of the strain ellipsoid for every grade is nearly parallel to the length of the metamorphic belt, suggesting that the flow direction of the synmetamorphic deformation was uniform along the belt. A map of strain zones within the Sambagawa high- P type metamorphic belt reveals that the metamorphic belt underwent a progressive bulk inhomogeneous shear deformation and that the high-grade zones represent a deep-seated boundary shear zone on the accretionary wedge between a subducting oceanic plate and the immobile rigid continental plate. 相似文献
4.
震旦纪—寒武纪转折期是地球演化的关键节点,这一时期的碳-氧同位素记录在塔里木保留完整却关注较少。选取苏盖特布拉克露头震旦系与寒武系交界地层实测采样,并开展了古生物、镜下鉴定、碳同位素漂移事件的综合分析,探讨了N1(BACE)、P1(ZHUCE)等碳同位素漂移事件的成因机制。样品的δ13Ccarb和δ18Ocarb相关系数(R2=0.05)、δ18Ocarb和Mn/Sr相关系数(R2=0.09)及岩石学特征表明,后期成岩改造并未导致碳-氧同位素的显著分馏,原始碳同位素特征得以基本保留。由下至上,在该剖面识别出P-1事件(δ13Ccarb峰值1.9‰2.4‰)、N1事件(-6.8‰-10.3‰)、P1事件(1.4‰4.1‰)、N2a-c事件(-0.4‰-2.8‰)、P2a-c事件(0.2‰0.6‰)和N3事件(-3.4‰)。综合碳同位素演化特征与古生物、年代学数据,确认了玉尔吐斯组底部硅质页岩与奇格布拉克组顶部藻云岩的分界面为塔里木震旦系与寒武系的分界线,并实现了该露头与老林、肖滩、三峡、西伯利亚、阿曼和摩洛哥剖面的地层对比。分析认为,塔里木北缘震旦纪—寒武纪转折期的碳漂移事件,更多受控于古海洋氧气含量变化引起的固碳率forg的波动。玉尔吐斯组早期海侵背景下的大规模缺氧事件导致的初级生产力和固碳率降低,是N1负漂移事件(BACE)的主因;随后海退中氧气含量的增加引起生产力重建和固碳率增加,形成了P1正漂移事件(ZHUCE)。这一成果性认识有助于塔里木盆地寒武纪古环境研究与深层超深层油气远景资源评价。 相似文献
5.
由于加筋土界面作用的复杂性,加筋土工程建设中铺设土工格栅时往往采用经验的方法,很大程度上造成了土工格栅的浪费及工程安全隐患,理清不同填料筋土界面作用的影响范围,有助于确定加筋土结构的合理加筋间距。为了揭示不同填料筋土界面作用的影响范围,采用4种不同类型的砂土与格栅在不同法向应力下进行了一系列的拉拔试验,并结合数字图像量测技术,分析了不同类型砂土下界面剪切带厚度、颗粒位移矢量、格栅拉拔阻力峰值及应变等演变规律。研究表明：界面剪切带厚度H随法向应力σv与砂土平均粒径d50的增加而增大,通过多变量拟合的方法,得到了H、σv与d50三者之间的函数表达式;格栅在拉拔过程中,砂土颗粒位移矢量以土工格栅为界有着显著的差别,格栅上部的颗粒位移矢量明显大于下部颗粒,且在格栅上下一定范围内会形成颗粒位移矢量集中带;拉拔阻力峰值随σv及d50的增加而增大;不同类型砂土各区段的格栅应变均表现出由前向后依次递减的趋势。 相似文献
6.
运动学涡度、极摩尔圆及其在一般剪切带定量分析中的应用 总被引：19，自引：0，他引：19
自然界中剪切带通常是由平行于剪切带方向的简单剪切和与之垂直的纯剪切共同作用的结果。利用运动学涡度(WK)可以定量地分析两者间的比值大小。一般摩尔圆只能应用于共轴应变,而极摩尔圆可应用于共轴与非共轴变形,并为求取WK提供了一种简便可行的方法。本文对一般剪切带的概念及其分类进行了描述,对运动学涡度和极摩尔国的原理及其应用进行了系统的论述,并在此基础上提出了几种新的实用的极摩尔国编制方法。 相似文献
7.
花岗伟晶岩型矿床是稀有金属矿床重要的类型之一。在花岗伟晶岩中,稀有金属元素Li、Be、Nb和Ta主要以独立矿物的形式存在,前人对稀有金属独立矿物在硅酸盐熔体中的溶解度及其影响因素展开了系统研究。本文综合分析了已有的实验数据,其结果表明,影响稀有金属独立矿物溶解度最为重要的2个参数是温度(T)和铝饱和指数(ASI)。因此本文建立了稀有金属独立矿物,尤其是铌锰矿和钽锰矿溶解度,与温度(T)和铝饱和指数(ASI)之间的定量关系: lg [w(Li)/10-6]=-0.37×[1 000/(T/K)]+4.56,R2=0.44 lg [w(BeO)/10-6]=-4.21×[1 000/(T/K)]+6.86,R2=0.91 lg [Ksp(Nb)/(mg2·kg-2)]=-(2.86±0.14)×ASI(Mn+Li)-(4.95±0.31)×[1 000/(T/K)]+(4.20+0.28),R2=0.86 lg [Ksp(Ta)/(mg2·kg-2)]=-(2.46±0.11)×ASI(Mn+Li)-(4.86±0.30)×[1 000/(T/K)]+(4.00+0.30),R2=0.80 式中,温度T为热力学温度,ASI(Mn+Li)(ASI=Al2O3/(CaO+Na2O+K2O+Li2O+MnO),摩尔分数比)和T的适用范围分别为0.6~1.2和1 073~1 373 K的范围内。上述公式为估算硅酸盐熔体中稀有金属含量提供了便利,为量化花岗伟晶岩成矿模型提供了基础。 稀有金属独立矿物溶解度随温度降低和铝饱和指数的增加而急剧降低,因此,在岩浆演化过程中,由岩浆侵位、分离结晶以及流体作用等因素引起的岩浆温度降低和铝饱和指数的增加,是导致稀有金属独立矿物结晶的主要机制。 相似文献
8.
Compressional waves velocity VP was measured during long-term experiments in a high-pressure vessel (in the range [10–75] MPa for confining and pore pressures). Experiments were carried out on a granite specimen prepared by a controlled heating treatment at 510 °C, which generated thermal cracks.
Data analysis is proposed by using an effective medium approach based on Kachanov's [Appl. Mech. Rev. 45 (1992)304] model. The elastic behaviour of the cracked rock is controlled by the crack density parameter which varies with confining and pore pressures due to crack closure. In order to model the progressive closure of cracks, we assume elliptical cracks with major axis 2c and aspect ratio . By using a conformal mapping technique, we derive the variation of the crack aspect ratio as a function of effective pressure, the effective pressure coefficient η depending on and Poisson's ratio ν0. As a result, we compute the crack density parameter and the elastic moduli of the cracked rock as a function of confining and pore pressures. To take into account the heterogeneity of the rock sample, a peak-like distribution of crack aspect ratios is introduced, which allows us to calculate the acoustic velocity VP for various effective pressures.
Comparison is made between theoretical and experimental values and shows that this simple model captures the essential features of the acoustic velocity variation: an increase of VP when pore pressure is decreased followed by a plateau for a threshold pore pressure. Best consistency between theoretical and experimental velocity values is obtained by introducing a second crack population with a higher mean aspect ratio and an irreversible closure mechanism as effective pressure is cycled. 相似文献
9.
Stefano Ceriani Neil S. Mancktelow Giorgio Pennacchioni 《Journal of Structural Geology》2003,25(12):2005-2021
The rotational behaviour of a rigid particle embedded in a linear viscous matrix undergoing cylindrical simple shear (Couette) flow was studied in 2D rock-analogue experiments. The influence of particle shape (elliptical vs. monoclinic), aspect ratio and the nature of the matrix/particle interface (lubricated vs. unlubricated) was investigated. Both matrix (PDMS) and lubricant (liquid soap) were linear viscous, with a viscosity ratio of ca. 104. Without lubricant, the rotational behaviour of all particles closely approximates the Jeffery theory. Lubricated monoclinic particles with the long diagonal initially parallel to the shear direction show back rotation and approach a stable position. Lubricated elliptical particles initially parallel to the shear direction also show back rotation but only transiently stabilize. Weak planar zones in the matrix adjacent to unlubricated elliptical particles do not induce backward rotation. In general for elliptical particles, rotation rate as a function of orientation depends on axial ratio and thickness of the lubricant mantle. For thick mantles (initially >10% of the volume of the particle), rotation rates are faster than Jeffery theory. For very thin mantles they are markedly slower compared with thick mantles, particularly when the long axis is nearly parallel to the shear direction. Rotation rates are never strictly zero, so true stabilization does not occur. However, for more elongate particles (axial RATIO=6) rotation rates are so slow that a very strong shape preferred orientation would develop in a lubricated elliptical particle population. In experiments, the volume of lubricant is constant and the thickness adjacent to the long side of the particle progressively decreases with increasing strain. In natural examples of porphyroclast systems, the weak mantle continually develops by recrystallization and/or cataclasis of the rigid clast core and a steady state between production and thinning could be attained, potentially leading to true stabilization for particles with a high axial ratio. 相似文献
10.
Pascale Bnzeth Donald A. Palmer David J. Wesolowski 《Geochimica et cosmochimica acta》2008,72(10):2429-2453
The dissolution and precipitation rates of boehmite, AlOOH, at 100.3 °C and limited precipitation kinetics of gibbsite, Al(OH)3, at 50.0 °C were measured in neutral to basic solutions at 0.1 molal ionic strength (NaCl + NaOH + NaAl(OH)4) near-equilibrium using a pH-jump technique with a hydrogen-electrode concentration cell. This approach allowed relatively rapid reactions to be studied from under- and over-saturation by continuous in situ pH monitoring after addition of basic or acidic titrant, respectively, to a pre-equilibrated, well-stirred suspension of the solid powder. The magnitude of each perturbation was kept small to maintain near-equilibrium conditions. For the case of boehmite, multiple pH-jumps at different starting pHs from over- and under-saturated solutions gave the same observed, first order rate constant consistent with the simple or elementary reaction: .
This relaxation technique allowed us to apply a steady-state approximation to the change in aluminum concentration within the overall principle of detailed balancing and gave a resulting mean rate constant, (2.2 ± 0.3) × 10−5 kg m−2 s−1, corresponding to a 1σ uncertainty of 15%, in good agreement with those obtained from the traditional approach of considering the rate of reaction as a function of saturation index. Using the more traditional treatment, all dissolution and precipitation data for boehmite at 100.3 °C were found to follow closely the simple rate expression:
Rnet,boehmite=10-5.485{mOH-}{1-exp(ΔGr/RT)}, with Rnet in units of mol m−2 s−1. This is consistent with Transition State Theory for a reversible elementary reaction that is first order in OH− concentration involving a single critical activated complex. The relationship applies over the experimental ΔGr range of 0.4–5.5 kJ mol−1 for precipitation and −0.1 to −1.9 kJ mol−1 for dissolution, and the pHm ≡ −log(mH+) range of 6–9.6. The gibbsite precipitation data at 50 °C could also be treated adequately with the same model:Rnet,gibbsite=10-5.86{mOH-}{1-exp(ΔGr/RT)}, over a more limited experimental range of ΔGr (0.7–3.7 kJ mol−1) and pHm (8.2–9.7). 相似文献
11.
A new method to estimate strain and competence contrast from natural fold shapes is developed and verified by analogue and numerical experiments. Strain is estimated relative to the nucleation amplitude, AN, which is the fold amplitude when the amplification velocities caused by kinematic layer thickening and dynamic folding are identical. AN is defined as the initial amplitude corresponding to zero strain because folding at amplitudes smaller than AN is dominantly by kinematic layer thickening. For amplitudes larger than AN, estimates of strain and competence contrast are contoured in thickness-to-wavelength (H/λ) and amplitude-to-wavelength (A/λ) space. These quantities can be measured for any observed fold shape. Contour maps are constructed using existing linear theories of folding, a new nonlinear theory of folding and numerical simulations, all for single-layer folding. The method represents a significant improvement to the arc length method. The strain estimation method is applied to folds in viscous (Newtonian), power-law (non-Newtonian) and viscoelastic layers. Also, strain partitioning in fold trains is investigated. Strain partitioning refers to the difference in strain accommodated by individual folds in the fold train and by the whole fold train. Fold trains within layers exhibiting viscous and viscoelastic rheology show different characteristic strain partitioning patterns. Strain partitioning patterns of natural fold trains can be used to assess the rheological behaviour during fold initiation. 相似文献
12.
The influence of vorticity and rheology of matrix material on the development of shape-preferred orientation (SPO) of populations of rigid objects was experimentally studied. Experiments in plane strain monoclinic flow were performed to model the fabric development of two populations of rectangular rigid objects with object aspect ratios (Rob) 2 and 3. The density of the rigid object populations was 14% of the total area. Objects were dispersed in a Newtonian and a non-Newtonian, power law matrix material with a power law exponent n of 1.2. The kinematic vorticity number (Wn) of the plane strain monoclinic flow was 1, 0.8 and 0.6 with finite simple shear strain of 4.6, 3.0 and 0.9, respectively. In experiments with Rob=3, the SPO is strongly influenced by Wn and the material properties of the matrix. Deformation of a power law matrix material and low Wn resulted in a stronger SPO than deformation of a linear viscous matrix and high Wn. Strain localization coupled with particle interaction plays a significant role in the development of a shape-preferred orientation. High strain simple shear zones separate trains of rigid objects that are surrounded by low strain zones with Wn lower than the bulk Wn. In fabrics involving populations of objects with Rob=2, rheology of the matrix materials does not systematically influence the intensity of the SPO. 相似文献
13.
为评估TRMM 3B42（TRMM）和新一代GPM IMERG（GPM）卫星降水产品精度,基于国内824个气象站点日降水数据,选用相关系数（R）、相对误差（ER）和公正先兆评分（SET）等指标,对比分析了二者在中国大陆和九大流域内逐日、逐月尺度的观测精度。研究表明:①在日尺度上,中国大陆内的GPM降水数据精度整体优于TRMM,二者的R、ER和SET分别达到了0.73、2.03%、0.36和0.70、3.75%、0.33;②GPM和TRMM日降水数据在海河流域、淮河流域、长江流域、珠江流域、东南诸河流域呈现较高的观测精度,在松辽流域、黄河流域、西南诸河片区精度次之,在内陆河片区相对最低;③在月尺度上,中国大陆内的GPM冬季降水精度明显好于TRMM,这是由于GPM提高了对弱降水和固态降水的观测能力。总体上,GPM降水产品在中国各大流域精度较好且优于TRMM,表明其在流域降水研究及水文模拟中将有较好的应用前景。 相似文献
14.
斜向扩张是超慢速扩张洋中脊独特的构造特征,其地形分段特征明显区别于经典的快速-慢速端元洋中脊模型,是理解超慢速扩张洋中脊地质过程的重要切入点。基于西南印度洋中脊Indomed-Gallieni和Shaka-DuToit段多波束地形数据,分析了不同斜向扩张角度(α)洋中脊的地形分段样式。其中,46.5°~47.5°E(α=5°)、16°~25°E(α=10°)和48.5°~52°E(α=15°)为近正向扩张段,发育雁列式叠置的中央火山脊;47.5°~48.5°E(α=50°)和16°~25°E(α=60°)为斜向扩张段,仅在洋脊段中部形成中央火山脊。利用有限差分+颗粒法(FD+MIC)数值模拟技术研究了洋中脊应变分布特征对不同α值的响应,结合地形分析,认为斜向扩张角度和温度异常分布共同控制了洋中脊地形分段样式。近正向扩张洋中脊(α＜20°)在温度异常处形成地壳伸展应变的集中区,有利于岩浆汇聚,发育雁列式叠置的中央火山脊,其位置随温度异常分布的变化而改变;斜向扩张洋中脊(α>20°)地壳伸展应变集中区的位置受斜向扩张几何样式控制,在洋脊段中部发育中央火山脊,对温度异常不敏感,形成位置长期固定的岩浆活动中心。 相似文献
15.
准噶尔盆地东南缘烃源岩演化与油气成因复杂,采用岩石热解、色谱-质谱、碳同位素等有机地球化学分析技术,对该区二叠系芦草沟组烃源岩地球化学及其成烃演化特征进行了详细调查。结果表明,不同成熟度的二叠系芦草沟组烃源岩有机质丰度和有机类型差异显著,烃源岩有机碳、生油潜量(S1+S2)分布范围分别为0.43%~12.89%(均值2.84%)、0.52~77.24 mg/g,烃源岩质量可从低熟时的“极好”级别降低至高成熟时的“中等-差”级别(Rc≈0.54%~1.93%);有机质类型可从低熟时的Ⅰ-Ⅱ1型变化为高成熟时的Ⅱ2-Ⅲ,指示对高-过成熟烃源岩的有机质类型与生烃潜能评价需要进行评价参数的适当恢复。二叠系芦草沟组烃源岩生物标志物特征显著:姥鲛烷相对于植烷有微弱优势,Pr/Ph值分布范围为0.92~1.81(均值1.22),指示弱还原的湖相沉积环境;C27-、C28-、C29-规则甾烷呈斜直线型分布;C28-规则甾烷丰度偏高(C28/C29-规则甾烷均值为0.96)、升藿烷系列丰度偏低、伽马蜡烷发育,反映二叠系芦草沟组烃源岩咸化和/或水体分层的原始沉积环境。油-油、油-源对比表明,芦草沟组原油主要来自芦草沟组烃源岩。烃源岩地质地球化学分析表明,深浅层不同成熟度芦草沟组烃源岩均有发育,该区具有较好的生烃物质基础,具有寻找不同埋深油气藏的重要勘探前景。 相似文献
16.
17.
S. E. JOHNSON 《Journal of Metamorphic Geology》1990,8(1):13-30
Porphyroblasts of garnet and plagioclase in the Otago schists have not rotated relative to geographic coordinates during non-coaxial deformation that post-dates their growth. Inclusion trails in most of the porphyroblasts are oriented near-vertical and near-horizontal, and the strike of near-vertical inclusion trails is consistent over 3000 km2 . Microstructural relationships indicate that the porphyroblasts grew in zones of progressive shortening strain, and that the sense of shear affecting the geometry of porphyroblast inclusion trails on the long limbs of folds is the same as the bulk sense of displacement of fold closures. This is contrary to the sense of shear inferred when porphyroblasts are interpreted as having rotated during folding.
Several crenulation cleavage/fold models have previously been developed to accommodate the apparent sense of rotation of porphyroblasts that grew during folding. In the light of accumulating evidence that porphyroblasts do not generally rotate, the applicability of these models to deformed rocks is questionable.
Whether or not porphyroblasts rotate depends on how deformation is partitioned. Lack of rotation requires that progressive shearing strain (rotational deformation) be partitioned around rigid heterogeneities, such as porphyroblasts, which occupy zones of progressive shortening or no strain (non-rotational deformation). Therefore, processes operating at the porphyroblast/matrix boundary are important considerations. Five qualitative models are presented that accommodate stress and strain energy at the boundary without rotating the porphyroblast: (a) a thin layer of fluid at the porphyroblast boundary; (2) grain-boundary sliding; (3) a locked porphyroblast/matrix boundary; (4) dissolution at the porphyroblast/matrix boundary, and (5) an ellipsoidal porphyroblast/shadow unit. 相似文献
Several crenulation cleavage/fold models have previously been developed to accommodate the apparent sense of rotation of porphyroblasts that grew during folding. In the light of accumulating evidence that porphyroblasts do not generally rotate, the applicability of these models to deformed rocks is questionable.
Whether or not porphyroblasts rotate depends on how deformation is partitioned. Lack of rotation requires that progressive shearing strain (rotational deformation) be partitioned around rigid heterogeneities, such as porphyroblasts, which occupy zones of progressive shortening or no strain (non-rotational deformation). Therefore, processes operating at the porphyroblast/matrix boundary are important considerations. Five qualitative models are presented that accommodate stress and strain energy at the boundary without rotating the porphyroblast: (a) a thin layer of fluid at the porphyroblast boundary; (2) grain-boundary sliding; (3) a locked porphyroblast/matrix boundary; (4) dissolution at the porphyroblast/matrix boundary, and (5) an ellipsoidal porphyroblast/shadow unit. 相似文献
18.
If the particle paths are known for deforming continuous media such as rocks, the strain is determined at all stages of the deformation. The particle paths are studied for various types of simultaneous combinations of pure shear and simple shear. Any kind of progressive plane homogeneous strain can be expressed as a simultaneous superposition of pure shear and simple shear by selecting the proper ratio between the two strain rates and the proper angle between the slide direction of the simple-shear part and the principal axes of the pure-shear part. In the cases studied — except one — the angle between the slide direction of the simple-shear part and the principal strain rate
of the pure-shear part is 45°. Several combinations of the simple-shear rate, γ, and the pure-shear rate,
, are tested. These combinations give particle paths varying from sets of straight parallel lines to orthogonal hyperbolas. Distorted hyperbolas, ellipses and circles constitute the particle paths at intermediate
ratios. From the particle-path equations — which are found by integration of the rate-of-deformation equations — the strain ellipse is readily determined at any stage of the deformation. One particularly intriguing result is the rotating and pulsating strain ellipse found in the cases when the particle paths are closed curves (ellipses). Application of the results to various fold-, thrust- and inclusion structures is suggested. In an appendix the treatment of rotational deformation as a superposition of irrttational strain and rigid rotation is considered for comparison. 相似文献
19.
内蒙古红花沟金矿控矿构造研究 总被引：1，自引：0，他引：1
红花沟矿区变质岩遭受了三期韧性变形（D1、D2、D3）和多期脆性变形的改造。含金石英脉产于D3期伴生的韧性剪切带中。矿脉的分布、产状和形态严格受成矿期构造运动及构造形态的控制。中生代D3期韧性剪切带再度活动,形成本区主要成矿期。构造的继承性活动控制了矿化的多期次富集。 相似文献
20.
为研究应变速率对原状膨胀土力学性状的影响,通过GDS三轴试验系统进行了不同速率和围压下的固结不排水三轴剪切试验,分析了应力−应变曲线、孔隙水压力、剪切强度以及破坏模式随应变速率的变化规律。结果表明：不同应变速率下,膨胀土应力−应变曲线均呈应变硬化型。随着应变速率的增加,不排水剪切强度单调递增,引入应变速率参数ρ0.9后发现,不排水强度增长率为14.3%～23.2%,平均值为18.4%。低围压下,应变速率对孔隙水压力影响较小,随着围压的增大,孔隙水压力的发展趋势由软化型转变为硬化型,孔隙水压力峰值随应变速率的增大而减小。原状膨胀土应变速率效应与其多裂隙性密切相关,破坏形式表现为小应变速率下主剪切带与次剪切带共存,大应变速率下仅有主剪切带,裂隙或多剪切带的出现强化了膨胀土强度的应变速率效应。 相似文献