Hard-rock LHD cost estimation using single and multiple regressions based on principal component analysis

In feasibility studies and mine planning, accurate and effective tools and methods facilitating cost estimation play an important role. Load-Haul-Dump (LHD) machines are a key loading and haulage equipment in most of the underground metal mines and hard rock tunnels. In this paper, a cost estimation model of these vehicles has been presented in the form of single and multivariable functions. These functions have been provided on the basis of costs types (i.e. capital and operating costs) and motor types (diesel and electric). Independent variables, in the single regression analysis is bucket capacity and in Multiple Linear Regression (MLR) analysis include bucket capacity, overall width, overall machine height and horse power (HP). The MLR is conducted in three steps. First, with the help of Principal Component Analysis (PCA), correlation between independent variables is omitted. Thereafter, significant PCs are selected and used as independent variables in the MLR functions. Finally, the cost relationships are established as functions of initial LHD variables. The mean absolute error rates are 11.59% and 6.87% for the single and multiple linear regression functions, respectively.     

基于全寿命成本的桥梁车道数决策研究

提出桥梁由于维护导致的维护间接成本改进模型,建立优化目标函数.在现有劣化模型基础上,研究桥梁结构在最优维护策略下寿命周期内荡态变化规律,以此为约束条件,提出全寿命优化设计方法的关键技术和设计框架,并编制相应的决策支持系统.桥面铺装属易损结构,其维护对交通将产生很大的干扰.以一座桥梁车道数(宽度)的决策为研究对象,根据桥梁全寿命设计理念,由桥面铺装的劣化-维护规律,对桥梁设计方案的决策进行新的尝试,证明了该方法的有效性和可行性.桥梁全寿命优化设计方法不但能考虑桥梁劣化和维护过程中的不确定性,而且能够合理规划桥梁服役期内的维护方案,平衡建造成本和维护成本,起到优化资源、保护环境的作用.     

基于综合集成的工程造价测算系统研究

文章分析了目前我国工程造价领域存在的现状问题，从综合集成的角度探讨了构建信息集成为基础、组织集成为架构、方法集成为工具的三位一体的工程造价测算系统，为解决造价测算精度、效率及资源耗费等问题提供了有效的途径。     

铁路桥梁混凝土工程造价大数据计算模型优化设计

基于大数据分析,对铁路桥梁混凝土工程造价计算模型的优化进行了研究。通过分析BP神经网络模型原理,发现该模型多输入多输出因素的非线性网络关系处理能力与本工程造价计算的非线性映射关系相吻合。利用计算机软件MATLAB中的BP神经网络工具箱进行搜索和查询,对于所采集得到的混凝土工程样本数据进行学习训练,把各项模型模拟数据结果和实际得到的样品数据结果进行比较分析,本研究构建的BP神经网络工程造价计算模型的误差率为3.29%,可满足铁路桥梁混凝土工程造价计算的精度要求。     

谈隧道监控量测数据分析的方法

通过利用Excel办公软件及函数回归分析的方法,对施工过程中收集的监控量测数据进行了详细系统的分析处理,指出该方法简单、方便、科学,分析数据准确、快捷,为隧道施工及时提供监控信息,可更好的指导隧道施工。     

Safety risk analysis based on a geotechnical instrumentation data warehouse in metro tunnel project

Lack of complete information is the major factor causing accidents on metro tunnel projects. Safety risk control requires a comprehensive analysis of instrumentation data integrated with other safety related data. Based on a multidimensional data model, a safety-oriented geotechnical instrumentation data warehouse is established to integrate all the data from heterogeneous data sources, not only for quick retrieval of information on site, but also for further analysis. As one of the most important safety indicators, ground settlement is analyzed to take advantage of the data warehouse. A double Gaussian model is proposed to represent the settlement trough over twin tunnels. Moreover, a revised trough width parameter is proposed to represent the scope of safety risk areas. The ground loss is found to grow in a pattern that can be represented by a logistic curve. The first derivative of ground loss is applied to represent the evolution of safety risk.     

Probabilistic assessment of tunnel construction performance based on data

A probabilistic model for estimating tunnel construction time is learnt with data from past tunnel projects. The model is based on the Dynamic Bayesian Network technique. The model inputs are determined through an analysis of data from three tunnels built by means of the conventional tunneling method. The data motivate the development of a novel probability distribution to describe the excavation performance. In addition, the probability of construction failure events and the delay caused by such failures are estimated using databases available in the literature. The model is applied to a case study, in which it is demonstrated how observations from the tunnel construction process can be included to continuously update the prediction of construction time.     

公路隧道二次衬砌厚度检测及统计分析

运用地质雷达对忻州—保德高速公路官地坪2号隧道进行衬砌厚度和衬砌背后空洞检测,对检测数据进行统计分析,得到衬砌厚度偏差值分布规律,明确了衬砌厚度及衬砌背后空洞在衬砌施工中较难避免,建议公路工程质量验收规范对衬砌厚度验收条件适当放宽。     

基于历史文脉延续的城市商务中心区规划设计

以宝鸡市陇县东部商务中心区规划设计为例,探讨了在规划设计中如何营造城市历史文化氛围,提出了历史为基,山水为实,尊重自然,面向未来的规划理念,旨在通过剖析规划设计方案,为城市建设中如何减少"千城一面"的城市问题提供参考。     

Damage identification of a tunnel liner based on deformation data

A new system identification approach based on tunnel deformation data is proposed to find the damage in the tunnel liner. For this, an inverse problem in which deformation data and dead load of concrete lining are known a priori is introduced to estimate the degree and location of the damage. Models based on uniform reduction of stiffness and smeared crack concept are both employed and the efficiency and relative advantage are compared with each other. Numerical analyses are performed on the idealized tunnel structure and the effect of white noise, common in most measurement data, is also investigated to better understand the suitability of the proposed models. As a result, model 1 based on uniform stiffness reduction method is shown to be relatively insensitive to the noise, while model 2 with the smeared crack concept is proven to be easily applied to the field situation since the effect of stiffness reduction is rather small. Finally, real deformation data of a rail tunnel in which health monitoring system is in operation are introduced to find the possible damage and it is shown that the prediction shows quite satisfactory result.     

基于大数据技术的工程造价数据处理与应用研究

为了解决目前工程造价面临的工程数据量大、工程数据种类繁杂以及稳定性差等特点,在工程数据采集的基础上,以某市城区生活用水改造工程为依托通过混沌人工鱼群算法从工程概况、工程量、造价费用等方面构建项目级造价数据体系,进一步提出工程造价大数据应用流程,为工程造价数据采集提供借鉴意义,并提出将造价大数据技术与BIM技术、云平台相结合的模式,进一步降低大规模数据存储成本,最大限度实现无纸化办公、减少社会资源消耗、提高造价工作效率。     

谈工程中的成本测算

结合工作经验,介绍了建筑工程中定额及工程量清单计价背景下的成本要素,明确了成本测算的范围与原则,并对成本测算中人、材、机械、措施四大要素中常见的一些情况进行了分析,为成本的控制工作奠定了基础。     

基于大数据分析的工程造价专业人才需求及目标薪酬实证研究

伴随着我国城镇化进程的加快和"一带一路"的有序推进,建筑行业发展前景巨大,市场对工程类人才需求持续增长。借助聚焦爬虫定向抓取前程无忧互联网招聘平台中涉及工程造价专业的9 443条招聘信息,分析工程造价专业人才需求特征,延伸构建了有序选择模型定量探究工程造价专业人才目标薪酬影响因素。研究显示,工程造价专业人才需求呈现区域非均衡性、学历普遍化、工作经验具体化、岗位需求及业务能力综合化等特征,六类能力需求差异度大。目标薪酬对专业资格认证需求正效应显著;薪酬越高工作经验要求较长、学历要求较高;薪酬等级与城市等级有一定联系,超一线城市与其他级别城市薪酬差异明显。大数据分析为各类高校建立适应市场需求的工程造价专业人才培养模式提供一定的数据支持。     

基于灰色理论的市政排水工程造价估算方法

结合市政排水工程的特点,针对传统的工程造价估算方法的局限性,用灰色理论估算模型对排水工程造价进行了估算,为市政工程造价估算提供了有效的方法。     

基于GIS的线路主要结构物费用估算算法设计

利用GIS系统中Arc Catalog地理数据库及属性选择功能,收集空间结构物工程实例并创建了文件地理数据库,针对某拟建项目,通过构造查询表达式在文件地理数据库中进行筛选,分别得到拟建空间结构物的工程造价基数及相关系数,从而解决了路基、桥梁及隧道工程造价估算的问题。     

基于矩阵模式热经济学的(火用)成本分析

以基本的空调系统制冷循环为基础,提出了利用矩阵模式热经济学原理对(火用)成本进行分析的思路,并叙述了建立事件矩阵A及其补充方程的方法.冷水机组 燃气锅炉方案的冷量(火用)成本和热量(火用)成本的计算结果与用其他方法计算的结果接近,并叙述了产生差异的主要原因.     

隧道开挖过程中施工监测及其数据分析

对隧道施工监测的内容、手段、技术等方面进行了简单的介绍,根据现场的实测数据对隧道的位移发展趋势进行了分析,并根据其发展趋势确定了最佳的施工方案,指出隧道施工监测对保障施工安全、指导施工、优化设计具有重要的意义。     

基于资源配置的施工阶段工程造价优化分析

本文基于施工阶段现场人力、机械设备等资源的配置,并以实际工程具体数据为例,对施工过程的管理活动进行了有效的优化,从而降低了建筑施工过程中的工程造价,使项目在施工过程中对资源的利用更加高效、成本更低。     

Life cycle cost analysis based on the fundamental cost contributors for asphalt pavements

A life cycle costing system should include the key variables that drive future costs in order to provide a framework for reducing the risk of under- or overestimating the future costs for maintenance and rehabilitation activities. In Sweden, price of oil products is mostly affected by the global economy rather than by the national economy. Whereas the price index of oil products has had a high fluctuation in different time periods, the cost fluctuation related to labour and equipment has been steady and followed the consumer price index (CPI). Contribution of the oil products was shown to be more than 50% of the total costs regarding construction and rehabilitation of asphalt pavements in Sweden. Consequently, it was observed that neither Swedish road construction price index (Vägindex) nor CPI has properly reflected the price trend regarding the asphalt pavement construction at the project level. Therefore, in this study, a framework is suggested in which energy- and time-related costs are treated with different inflation indices in order to perform a better financial risk assessment regarding future costs.     

基于CDIO理念的工程估价课程教学模式改革

将提高学生的实践经验和执业技能作为目标,以CDIO理念为指导,对工程估价课程教学模式进行改革,以求夯实理论基础,强化实践环节,以赛促学,以赛练兵。实践表明,依托学科竞赛平台的实战教学改革,使学生整体实践水平明显提高,从业技能明显增强,学生连续三年蝉联全国算量总冠军。文章对这一教学模式改革作了介绍和探索。