边坡岩体力学参数估算与应用

实例介绍边坡岩体抗剪强度参数的估算与应用。     

论全生命周期造价管理在建筑设计中的应用

在分析全生命周期造价管理在建筑设计中应用的必要性及重要意义的基础上,从建设方案、造价计算、BIM技术三方面,探讨了建筑设计中全生命周期造价管理的具体措施,旨在为提升我国建筑设计的全生命周期造价管理水平提供参考。     

环境岩土工程研究进展

该文总结了近年来国内外环境岩土工程领域的研究进展,主要包括：①环境岩土工程调查与评价方法。重点介绍了电阻率静力触探探头、与静力触探结合的传感器薄膜界面探头、光纤光学化学传感器、X荧光分析仪等在场地污染物分布和污染程度识别技术;综述了土工离心技术应用于土体及地下水中污染物运移,及污染场地修复的研究现状;总结了污染场地分类方法和风险评价模型。②城市固体废物填埋技术。介绍了固废填埋场多场相互作用的主要耦合模型理论,总结了固废生化反应-骨架变形-水气运移-溶质迁移模型及应用;提出了填埋场污防污屏障服役寿命的定量评价方法。③工业固体废弃物资源化再利用技术。介绍了废弃电石渣和木质素加固过湿土、粉土路基的性能和工程应用;总结了固化污泥和淤泥技术的研究现状。④工业污染地基处理技术。总结了工业污染场地主要修复技术;介绍了固化污染土稳定技术、新型固化剂和稳定剂的研发进展;总结了常见竖向隔离墙技术,介绍了土-膨润土系竖向隔离墙长期防渗防污性能的研究进展;介绍了曝气法处理有机污染地下水技术的研究进展。     

复杂建筑场地土体抗剪强度参数新型原位测试试验研究

法国Phicometre钻孔线性剪切试验系统,为目前世界上最先进的新型体抗剪强度参数原位测试技术。选取云南数个复杂建筑场地,开展这一技术的工程应用研究,对不同成因、不同状态的黏土、粉质黏土、残积土、圆砾、全风化岩等抗剪强度参数进行了现场测试试验。试验结果表明,该技术能直接、连续、快速地测定土体抗剪强度参数;并且,获得的测试数据离散性小,线性相关度高,最低为0.95,平均达0.99。相比其他测试方法,测试结果较为可靠,可为该技术的推广应用和类似工程原位测试提供参照。     

计算机在工程检测中的应用

计算机办公软件应用已逐渐普及,但是在某些专业数据处理方面还没有相应的软件可以使用,因此编写一些适合自己工作的程序是很好的方案,这样的程序用起来会更得心应手。     

Experimental testing of cool colored thin layer asphalt and estimation of its potential to improve the urban microclimate

Urban Heat Island refers to the temperature increase in urban areas compared to rural settings, exacerbating the energy consumption of buildings for cooling. The use of highly reflective materials in buildings and urban structures reduces the absorbed solar radiation and contributes to mitigate heat island. This paper presents the results of a study aiming to measure and analyze the solar spectral properties and the thermal performance of 5 color thin layer asphalt samples in comparison to a sample of conventional black asphalt. Computational fluid dynamics (CFD) simulation is used for evaluating the thermal and energy impact of applying the samples in outdoor spaces (roads). The spectrophotometric measurements showed that the colored thin layer asphalt samples are characterized by higher values of solar reflectance compared to the conventional asphalt, which is mainly due to their high near infrared solar reflectance. From the statistical analysis of the surface temperatures it was found that all the colored thin layer asphalt samples demonstrate lower surface temperatures compared to conventional asphalt. The maximum temperature difference recorded was for the off-white sample and was equal to 12 °C. The CFD simulation results show that surface and air temperatures are decreased when applying the color thin layer sample.     

数据采集系统在工程机械测试中的应用

本文介绍了基于虚拟仪器的数据采集分析系统WaveBook,及数据采集分析软件DasyLab,并以装载机动态压力测试为例,说明该套系统在工程机械测试中比传统仪器具有明显的优越性。     

Probable maximum loss estimation in earthquakes: an application to welded steel moment frames

An approach to the evaluation of the damageability of buildings and the determination of probable maximum loss (PML) values is presented and applied to welded steel moment frame buildings. PML is defined as the loss that has a given (usually 10%) probability of exceedance in a specified number of years from earthquake ground shaking. A Markov Model developed is used in a Monte Carlo simulation to determine damage statistics, from which PML values are determined. Four sites within the Los Angeles area are considered, as are a range of building damageabilities from very low to very high. Specific assessments are made for welded steel moment frame buildings representative of the post-Northridge understanding of damageability. PML values are shown to be very sensitive to the probability of loss exceedance, the time period considered, the number of buildings in the portfolio, and the lower bounds of earthquake magnitude and ground motions considered. The number of buildings considered in the PML assessment is shown to be very important as a means of reducing PML values. The use of MMI ground motion characterization is assessed and found to be wanting. A comparison of PML results with other damageability measures (both average and 10% exceedance) for four sites, including different ground motions and earthquakes, and a maximum probable loss associated with the closest serious earthquake, indicates that these other measures are not good estimators of the full probabilistic PML that considers in a consistent manner both site ground motion and building performance uncertainty. © 1997 John Wiley & Sons, Ltd.     

岩土参数随机场空间最优估计精度分析与特异值研究

阐述了克立格方差的特点, 并结合实际对岩土参数随机场空间最优估计的局部估计精度进行了分析, 探讨了影响岩土参数空间最优估计精度的特异值的处理方法。研究结果表明, 对存在特异值的岩土参数随机场进行估计时,应用指示克立格法能够获得符合实际的空间最优估计效果。     

Reformulation of the family life-cycle concept: implications for residential mobility

The author examines the utility of assuming a traditional life cycle framework in social science theory in view of the diversification of patterns of family and non-family structure and behavior. A more comprehensive life cycle model encompassing varied household types is suggested. The appropriateness of this model is investigated, with particular reference to single-headed family households and primary households in the United States     

Diagnostic load testing and assessment of existing bridges: examples of application

Load testing method is a significant tool in the assessment of bridge safety. One type of load tests is diagnostic load testing, the aim of which is to establish a comparison between real bridge behaviour and analytical calculation. It can be used either as acceptance test of the structures or as an estimation tool for the load carrying capacity of the already existing structures that have been in service for some time. This article presents diagnostic load tests and three examples of their application to various bridge structures and emphasises their diagnostic potential for assessment. In the majority of cases of diagnostic load tests presented in the literature, the experimental results (deflections, strains, etc) are very close or lower than the predicted ones and for this reason, such tests are expected to validate the existing structure. However, in the cases presented here, it is shown how the experimental results differ considerably from the expected ones. Since the theoretical and the experimental results of all three examples did not match, it was highly recommended to keep the matter under close investigation. A deep insight into the bridges showed serviceability and safety concerns and in some cases a repair/strengthening was necessary.     

Intake fractions of industrial air pollutants in China: estimation and application

Intake fractions, an emissions-intake relationship for primary pollutants, are defined and are estimated in order to make simple estimates of health damages from air pollution. The sulfur dioxide (SO2) and total suspended particles (TSP) intake fractions for five cities of China are estimated for the four main polluting industries-electric power generation, mineral (mostly cement) products industry, chemical process industry and metallurgical industry (mainly iron and steel smelting). The Industrial Source Complex Long Term (ISTLT3) model is used to simulate the spatial distribution of incremental ambient concentrations due to emissions from a large sample of site-specific sources. Detailed population distribution information is used for each city. The average intake fractions within 50 km of these sources are 4.4x10(-6) for TSP, and 4.2x10(-6) for SO2, with standard deviations of 8.15x10(-6) and 9.16x10(-6), respectively. They vary over a wide range, from 10(-7) to 10(-5). Although the electric power generation has been the focus of much of the air pollution research in China, our results show that it has the lowest average intake fraction for a local range among the four industries, which highlights the importance of pollutant emissions from other industrial sources. Sensitivity analyses show how the intake fractions are affected by the source and pollutant characteristics, the most important parameter being the size of the domain. However, the intake fraction estimates are robust enough to be useful for evaluating the local impacts on human health of primary SO2 and TSP emissions. An application of intake fractions is given to demonstrate how this approach provides a rapid population risk estimate if the dose-response function is linear without threshold, and hence can help in prioritizing pollution control efforts.     

Wavelets-based estimation of multivariate evolutionary spectra and its application to nonstationary downburst winds

This paper presents a wavelets-based approach for estimating evolutionary power spectral density (EPSD) functions of vector-valued nonstationary processes. This approach is based on the presumption that the time-varying rate of the modulation function of the process is slow as compared to the localized wavelet functions. This assumption leads to the relationships between wavelet coefficients and EPSDs, which are used for estimating EPSDs through wavelet coefficients calculated from time history samples. A parametric study is implemented to examine the efficacy of the approach for a host of evolutionary processes. Special emphases are placed on the influence of the wavelet functions, the number of time history samples and the wavelet scales on the accuracy of the estimations. The results of this study illustrate that this approach offers accurate EPSD estimation provided that sufficient numbers of time history samples are available and that the changes in the modulation functions with time are relatively slow as compared to the wavelets. Compared with the time–frequency spectra directly defined in terms of wavelet coefficients reported in literature, the EPSDs calculated from the wavelet coefficients using the proposed approach shed more physical insights to the processes. Finally, the proposed approach is used to analyze downburst measurement data, leading to an improved understanding of the time-varying frequency characteristics of nonstationary winds.     

旁压试验在某高层建筑场地原位测试中的应用

回顾了旁压试验的发展历程,详细介绍了旁压试验的原理及典型旁压曲线,简述某高层建筑场地的工程地质概况,分析了基床反力系数随着深度及土类的变化规律,为工程设计提供了科学的勘测数据。     

On the estimation of characteristic indoor air quality parameters using analytical and numerical methods

Indoor exposure to air contaminants penetrating from the outdoor environment depends on a number of key processes and parameters such as the ventilation rate, the geometric characteristics of the indoor environment, the outdoor concentration and the indoor removal mechanisms. In this study two alternative methods are used, an analytical and a numerical one, in order to study the time lag and the reduction of the variances of the indoor concentrations, and to estimate the deposition rate of the air contaminants in the indoor environment employing both indoor and outdoor measurements of air contaminants. The analytical method is based on a solution of the mass balance equation involving an outdoor concentration pulse which varies sinusoidally with the time, while the numerical method involves the application of the MIAQ indoor air quality model assuming a triangular pulse. The ratio of the fluctuation of the indoor concentrations to the outdoor ones and the time lag were estimated for different values of the deposition velocity, the ventilation rate and the duration of the outdoor pulse. Results have showed that the time lag between the indoor and outdoor concentrations is inversely proportional to the deposition and ventilation rates, while is proportional to the duration of the outdoor pulse. The decrease of the ventilation and the deposition rate results in a rapid decrement of the variance ratio of indoor to outdoor concentrations and to an increment of the variance ratio, respectively. The methods presented here can be applied for gaseous species as well as for particulate matter. The nomograms and theoretical relationships that resulted from the simulation results and the analytical methods respectively were used in order to study indoor air phenomena. In particular they were used for the estimation of SO2 deposition rate. Implications of the studied parameters to exposure studies were estimated by calculating the ratio of the indoor exposure to the exposure outdoors. Limitations of the methods were explored by testing various scenarios which are usually met in the indoor environment. Strong indoor emissions, intense chemistry and varying ventilation rates (opening and closing of the windows) were found to radically influence the time lag and fluctuation ratios.     

门座起重机金属结构应力测试及疲劳寿命估算

对某台在用门座起重机主要金属结构件进行了静态、动态强度测试,并对较大受力构件进行了剩余寿命估算,为设备的维护和安全使用提供了参考依据。     

腐蚀钢筋初锈时间的分布检验及参数估计

应用MATLAB提供的功能函数,确定了腐蚀钢筋初锈时间的寿命分布类型。进行了腐蚀初锈时间的分布类型判断、相关参数的极大似然估计,确定了钢筋初锈时间的概率密度函数,并绘制了各分布与腐蚀初锈时间的拟合分布及概率分布图。分析结果表明,钢筋初锈时间不拒绝服从对数正态分布,所作工作可为研究钢筋混凝土结构的耐久性概率研究提供理论参考价值。     

三维块段储量计算法(3DKD)的研究与应用

通过多年来对国际矿业界通行的储量计算方法的研究分析,结合我国的实际和国家有关储量计算标准,提出了一套既传承我国行业标准,又可以实现与世界接轨,同时也符合当今科技发展的主流方向的储量计算方法——三维块段法(3DKD法),并结合3DMine软件,对此方法的基本概念和方法进行说明。相信这一方法的应用,将是对我国传统块段法的一次变革,从理论性、实用性、操作性和规范性等方面具有重要的现实意义。