标准贯入试验测量击打能量的试验研究

标准贯入试验是最常用的勘察手段之一,具有历史悠久、操作简单、造价低廉、可参考和借鉴的经验丰富等优点。但传统的数标贯击数的方式缺乏理论支持,且试验过程中存在因设备差异和杆长不同带来的标准贯入击数的误差问题,通常的做法是采用测量击打能量来对锤击击数进行修正。本文在前人研究的基础上,开展标准贯入试验的击打能量测量的试验研究。具体的方法是通过实时采集钻杆在受自由落锤锤击时的加速度信号,并对高频波干扰进行低通滤波,并采用力量速度法将加速度物理量转化计算,实现在标准贯入试验过程中实时监测击打能量。通过在不同密度的砂土中采用此法进行试验,得到不同密实度相对应的击打能量呈规律性的不同的结论。国内在标准贯入试验的定量化与自动化方面的研究还较少,本文的研究对推动国内在此领域的进展有一定积极的意义。     

复盐法生产不同颗粒度三氧化钨工艺实践

介绍了运用"仲钨酸铵-钠复盐"法生产WO3的工艺流程及其优点,着重详细阐述复盐法生产不同颗粒度(粗、中、细、轻质)WO3的生产方法、相当规律等,实用性强。     

浅议饱和砂(粉)土的液化判别方法

砂(粉)土液化是地震中经常发生的主要震害之一,砂(粉)土液化受到多种因素的影响,关于液化的判别方法,国内外有很多种,每种方法都有一定的适用范围。通过实际工程中的标准贯入试验、静力触探试验、剪切波速试验综合进行液化判别,以准确判断砂(粉)土是否液化。     

两种杆径对砂层标准贯入试验击数的影响

近年来,随着国内钻探技术的不断提高,比规范规定直径42mm更粗的Ф50型钻杆越来越多地出现在标准贯入试验中（SPT）,本文以石家庄某工程为例,统计分析了SPT击数和钻杆杆径之间的关系。结果表明,标贯击数大小与钻杆杆径之间存在着显著的相关关系,若试验使用的钻杆不是标准的Ф42钻杆,则标贯击数宜进行修正。     

Inverse determination of the elastoplastic and damage parameters on small punch tests

The small punch test (SPT) is very useful in those situations where it is necessary to use small volumes of material. The aim of this paper is to create and validate a methodology for the determination of the mechanical and damage properties of steels from the load-displacement curve obtained by means of SPTs. This methodology is based on the inverse method, the design of experiments, the polynomial curve adjustment and the evolutionary multi-objective optimization, and also allows simulating the SPTs. In order to validate the proposed methodology, the numerical results have been compared with experimental results obtained by means of normalized tests. Two dimensional axisymmetric and three-dimensional simulations have been performed in order to allow the analysis of isotropic and anisotropic materials, respectively.     

A practical approach for performance-driven UML modelling of handheld devices - A case study

In this article, we present a performance engineering enhanced modelling methodology for designing embedded devices and describe the experiences we have gained in applying this methodology during the design of a DVB-H enabled handheld device. The methodology uses UML 2.0 to model the system following a strict separation of architectural and behavioural aspects of the system. For this purpose we employ the new composite structure diagram and show its advantages over already established approaches. This methodology specially aims on an easy application by non performance experts. From the model, a multiclass queueing network is generated for the analysis of the system performance. The configuration of hardware resources and resource demands is done using the standard SPT Profile which is extended where necessary. This makes queueing theory accessible to system designers even if they are not familiar with the underlying mathematics. In this way the acceptance of developers to use performance engineering in their daily work is increased. Special attention has been put on an easy evaluation of design alternatives. We describe our implementation and its seamless integration into a UML 2.0 CASE tool.     

运行参数对SPT器壁腐蚀影响的光谱诊断

影响稳态等离子发动机（简称＂SPT＂）器壁腐蚀的因素很多：鞘层电势、器壁形貌、离子轰击的能量分布等,利用数值模拟的方法研究腐蚀情况比较困难,计算结果和实验结果相差较大。本文基于发射光谱法,利用Avaspace光栅光谱仪对SPT通道器壁特征元素的谱线进行分析。通过测量不同质量流量和放电电压下的陶瓷器壁特征元素谱线强度随时间的变化,结合理论分析得出不同运行参数下发动机器壁腐蚀速率变化的规律。     

Evaluation of high temperature mechanical strength of Cr–Mo grade steel through small punch test technique

Remaining life assessment (RLA) of high temperature components calls for estimation current mechanical properties of the component material. For determination of mechanical properties of in-service components, large volumes of samples are required to be cut from components. The sample() removal warrants post-sampling repair by welding and mandatory post weld heat treatment. The time and the efforts involved in these exercises often limits the RLA to less reliable levels relying on the material’s original properties at the time of fabrication leading to over prediction.Research is being carried out for estimation of mechanical properties of materials by destructive testing of miniature samples under various modes. Small punch test (SPT) technology is one such technique which has generated significant interest of the researchers. However challenges exist to establish procedure of testing and development of field implementable characteristic co-relation between SPT parameters and material properties. Though reports are available on room temperature (RT) properties on variety of materials to a great extent, studies on estimation of high temperature properties through SPT are sparingly available. An attempt has been made to develop correlations between SPT parameters and high temperature mechanical properties of Cr–Mo grade material. This paper describes salient features of the test setup developed and used for conducting test at high temperature, experimental results on one of the Cr–Mo grade material followed by development of correlation equation for estimating tensile properties.     

某场地地震液化危害评价及地基处理建议

分析了砂土液化原理,结合工程实际,对某高速公路特大桥的液化场地土液化等级、危害性进行了评价,并结合工程特点,给出了切实可行的处理建议,从而保证该特大桥地基处理的效果。     

金山汉卡SPT图文系统图像格式分析

本文详细分析国内流行的金山ＳＰＴ图文系统的ＴＩＦＦ及特有ＳＰＴ图像文件的压缩及非压缩数据格式，并介绍其数据读取方法。