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1.
超声光栅测量液体体积弹性模量实验研究   总被引:1,自引:0,他引:1  
在利用超声光栅测液体声速的基础上,针对不同浓度的食盐(NaCl)溶液,研究超声波声速与溶液浓度的关系,并由此得出液体体积弹性模量与浓度的关系。实验结果表明,食盐(NaCl)溶液浓度与其体积弹性模量成近似线性关系。  相似文献   

2.
1. Introduction At present, the construction of large-scale reservoirworks has given rise to many large-scale reservoirareas, the stabilization of slopes in these reservoirdistricts will be influenced by water waves. Thecirculating hydraulic loading caused by the waveproduces a great force on the slope, and especiallyforms a vibration wave force on the boundary of water surface and the slope earth, and even breaks the water-soil interface, leading to the excess pore pressurechanging along diff…  相似文献   

3.
为构建人造板力学性能的无损检测系统,以纤维板为试材,利用振动无损检测法测定纤维板的动弹性模量,并与力学试验机测定的静弹性模量进行比较.结果表明:利用振动法测得纤维板弹性模量的精度好,动弹性模量与静弹性模量密切线性相关.  相似文献   

4.
Experiments of silt rock subjected to coupling loads were carried out on tailormade equipment. With a constant dynamic load, the behaviors of eight sets of siltite specimens were investigated with different axial static loads. The experimental results show that the modulus of the specimens under coupling loads increases at first and then decreases with the increase of axial static pressure. The failure model of the specimens also varies. Keeping the dynamic load constant, when the axial static pressure is low, the specimen breaks in two simply. With the increase of axial static pressure, the cone-shaped fragment appeares. When the axial static pressure reaches 90% of the static strength of rock, the specimen smashes into amount of small fragments.  相似文献   

5.
Experiments of silt rock subjected to coupling loads were carried out on tailormade equipment. With a constant dynamic load, the behaviors of eight sets of siltite specimens were investigated with different axial static loads. The experimental results show that the modulus of the specimens under coupling loads increases at first and then decreases with the increase of axial static pressure. The failure model of the specimens also varies. Keeping the dynamic load constant, when the axial static pressure is low, the specimen breaks in two simply. With the increase of axial static pressure, the cone-shaped fragment appeares. When the axial static pressure reaches 90% of the static strength of rock, the specimen smashes into amount of small fragments.  相似文献   

6.
混凝土冻融耐久性的试验研究   总被引:2,自引:0,他引:2  
以混凝土冻融耐久性为研究内容,用不同种类混凝土的抗压强度、动弹性模量、超声波声速等指标的损失率来表征冻融过程中混凝土的性能劣化状况,并系统比较了不同种类混凝土的抗冻性优劣.通过研究得出:无论是普通混凝土,还是高强混凝土或高性能混凝土,其动弹模损失率、抗压强度损失率、超声波声速损失率均随冻融次数的增加而增大;提高混凝土强度在一定程度上可以提高混凝土抗冻融性能;掺入高效减水剂、优质引气剂和优质掺合料等,高性能混凝土抗冻融性能比对应的基准混凝土性能显著改善,而且通过这样的技术措施,较低强度等级的混凝土也可以获得高抗冻性.鉴于超声波测试方法方便、快捷、准确。而且可以直接用于实际工程的混凝土性能检测,所以,与动弹模测试方法相比,采用超声波测试技术来评价实际工程中混凝土的耐久性劣化程度具有明显的优势.  相似文献   

7.
岩体空隙率计算方法新探讨   总被引:3,自引:0,他引:3  
通过理论分析,推导出岩体弹性波波速与空隙车间关系,并对其进行统计分析.同时进行岩体空隙率计算,并与现场测试结果对照,二者吻合.  相似文献   

8.
To study the bending strength of mass concrete under dynamic loading, the pure bending zone of three-graded concrete beam is considered as a three-phase composite composed of matrix, aggregate and interface between them on meso-level. Dynamic constitutive model considering strain-rate strengthening effect and damage softening effect is adopted to describe the cocrete and meso-element's damage. The failure mechanisms of beam under impact loading, triagle wave load, dynamic load coupling with initial static loading were simulated by using displacement-controlled FEM. Furthermore, stress-strain curve of the specimens and their dynamic bending strength were obtained. The results obtained from numerical simulation agreed well with experimental data.  相似文献   

9.
以岩石损伤力学为基础,以电阻率测量为手段,通过试验研究岩石在损伤过程中电性与力学性能之间的关系,建立以岩石弹性模量和电阻率变化为基础的损伤变量,通过定量分析岩石电性的变化过程,反演并分析岩石损伤状态,构建岩石宏观力学性能和电性之间的关系,建立岩石电阻率测试及评价岩石损伤状态的试验方法。  相似文献   

10.
敦煌莫高窟崖体顶部及陡坎地带表层松散的风化堆积物,在大风条件下极易发生滚石和流砂,威胁着游人和洞窟的安全.针对以往的加固保护措施,本研究提出了PS花管注浆加固新工艺,即利用打入风化堆积层的花管将PS浆液引入一定的深度固化,形成固化柱,再对表面喷洒PS,使注浆形成的固化柱与表面加固层连成一体.现场试验表明,除花管管径外,PS溶液浓度、堆积物组分以及含水量均对PS固化半径产生重要的影响.固化半径随着PS溶液浓度增大而减小,但是在较低含水量情况下,固化半径却随着堆积物中细颗粒含量的增大而显著增大.声波测试结果表明,经过PS固化后,地层波速增大20~70%,形成的固化体强度明显增大.试验证明,PS花管注浆形成的固化柱能将表面防风化加固层连成一体,将会提高莫高窟强风化地层的加固效果.  相似文献   

11.
INTRODUCTION The elastic properties of coating layers in coating materials are very important in the design and evaluation for engineering purpose. They can serve as ground knowledge in the selection of surface coatings for particular applications, and can be used to monitor the quality of physical processes (Every, 2002). Therefore, estimation of the elastic properties of coating layers is of great practical value. Much effort has been put into measuring the material properties of coatin…  相似文献   

12.
针对采空区内的松散岩体,运用三维有限差分法建立了数值模型对其进行分析;研究结果表明,在不同埋深条件下松散岩体的应力呈直线变化;对于水平应力,其斜率间的关系近似成指数关系;对于垂直应力,随埋深增大斜率没有变化;在不同冒落高度条件下,松散岩体的水平应力变化成多项式,次数随冒落高度依次升高;垂直应力变化曲线随冒落高度由直线逐渐变成对数曲线;在压实松散岩体过程中,应力在初始循环时步变化大;不同冒落高度条件下,循环时步随高度增大。  相似文献   

13.
INTRODUCTION Researchers continue to develop non-destructive methods to evaluate the effect of their impact on ag-ricultural products using high-tech methods. Non-destructive techniques sensing has been applied for obtaining fruit and vegetable quality index. Non-destructive method for measuring firmness us-ing sonic or vibration characteristics applied in pre-vious investigations was recently reviewed by Arm-strong (1989) and Liljedahl and Abbott (1994). The sonic vibration technique u…  相似文献   

14.
To evaluate the columnar jointed basalts in the dam site of Baihetan hydropower station in southwest China, we developed a basic conceptual model of single jointed rock mass. Considering that the rock mass deformation consists of rock block deformation and joints deformation, the linear mechanical characteristics of the cell (including the elastic joints and the nonlinear mechanical behaviors of the cell) with a combined frictional-elastic interface were analyzed. We developed formulas to calculate the rock block deformation, which can be adapted for multiple jointed rock mass and columnar jointed basalts. The formulas are effective in calculating the equivalent modulus of multiple jointed rock mass, and precisely reveal the anisotropic properties of columnar jointed basalts. Furthermore, the in situ rigid bearing plate tests were analyzed and calculated, and the types of loading-unloading curves and the equivalent modulus along different directions of columnar jointed basalts were obtained. The analytical results are in close compliance with the test results.  相似文献   

15.
岩体弹性模量沿地层埋深变化规律研究   总被引:1,自引:0,他引:1  
利用国内外关于地应力的实测资料,通过数值方法探讨我国岩体的重要力学参数——弹性模量沿地层埋深的变化规律:10km埋深以上基本是线性增加的,在10km埋深附近会急剧减小.以丹江口地区为例,依据其表层地应力和岩体弹性模量的试验数据,利用我国岩体弹性模量沿地层埋深的变化规律,反演该区几种主要岩石在不同埋深处的弹性模量.  相似文献   

16.
总结赋存环境对岩土体弹性波波速敏感性研究成果,阐明了赋存环境对波速的影响特征,提高了岩土体波速资料在应用中的科学性。  相似文献   

17.
基于正交设计方法,以铁粉、重晶石粉、石英砂为骨料,石膏为胶结剂进行拌和,研究福州某双洞隧道围岩相似材料的极限抗压强度、弹性模量、黏聚力、内摩擦角。 结果表明,不同配比的相似材料其物理力学参数值跨度较广,可以作为大部分岩体的相似材料进行物理模型试验。 通过大量试验,确定相似材料物理力学参数的影响因素并进行敏感性分析,最终确定材料的合理配比,较好地模拟出目标岩体的物理力学参数。  相似文献   

18.
TSP地震波波速与隧道围岩类别关系探讨   总被引:1,自引:0,他引:1  
介绍了TSP超前地质预报技术的基本原理和过程,提出了在TSP所测的波速预测隧道围岩类别时存在着预测结果偏大的问题,探讨了TSP地震波波速与隧道围岩类别关系。  相似文献   

19.
基于声速测试仪,利用时差法测量了超声波在不同浓度甘油溶液中传播纵波的速度,结合波动学理论间接求出了不同浓度下甘油溶液的体变模量.对甘油溶液的体变模量与其浓度的关系进行了定性和定量的研究与分析,给出了甘油溶液的体变模量与其浓度的关系图及线性拟合方程.研究结果表明,随着甘油溶液浓度的不断增加,甘油溶液的体变模量也随之增加,而且甘油溶液的体变模量与其浓度呈线性关系.这一研究结论在材料力学、化学工业以及进一步研究液体力学特性等方面有着重要的参考和应用价值.  相似文献   

20.
FOR THE GEO一TEEHNIEAL DESI,PARAMETERS OF 5011,EOMPARISON OF SEISMIE RESPONSES BASED ON DIFFERENT THE UNEVEN DISTRIBUTION OF THE DIFFERENT KINDS OF 5011 METHODS TO EVALUATE THE 5011 FUNETIONS.IN ADDITION, AND SAMPLING LOCATIONS DURING EXPLORATION AND I…  相似文献   

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