深部井壁冻结条件下的受力分析

由于煤矿深井井壁的质量直接影响了整个矿井安全,因此,有必要对井筒的内外受力进行监测。采用现场温度监测和进行受力分析来考察井壁的安全性;通过计算和测试,发现井壁受到冻结压力后在井壁浇筑一开始的时候增长较快,大致上表现出直线型增压型,然后开始曲线的增压段。冻结压力的数值受井壁土层层厚的影响比较大,而且表现出了不规则性。     

某矿冻结外层井壁受力监测与分析

为检查某矿井冻结井筒外壁的安全性,对该矿井井筒外壁两个水平的冻结压力、钢筋应力以及混凝土应变进行了受力变形监测。通过对实测数据的理论分析,得出外层井壁应力应变均满足设计要求,井筒外壁安全可靠。     

冻结法施工立井井筒井壁结构设计研究

简述了冻结法施工的井筒井壁结构形式,研究了钢筋混凝土双层井壁厚度的计算方法,并以内蒙古某矿井为工程背景,对考虑混凝土强度提高系数前、后的计算结果进行了对比分析,以减薄井壁厚度,从而减少矿井投资。     

地层冻结测温系统在煤矿信息化施工中的应用

为研究地层对井壁的影响,在井壁施工前对井筒整个地层进行综合分析,通过地层冻结测温系统对井筒实时监测,测量结果表明信息化施工技术能更准确、直观的为井壁施工和监测提供依据,可广泛应用于煤矿立井井筒建设。     

地下工程问题三轴模拟试验台及其应用

用于岩土工程和深部地下工程问题研究的、颇具特色的大型三轴物理模拟试验台于１９８６ 年在中国矿业大学建立并通过技术鉴定。该试验台有效试验净高２ ．４ ｍ ,有效试验直径达１ ．６ ｍ , 试验压力可达１１ ．０ ＭＰａ 。１０ 年来,利用这个试验台先后进行了人工冻结温度场、冻结壁的厚度与变形、冻结管受力与变形、深表土立井井壁受力以及地层加固后围岩与井壁相互作用等诸多课题的研究,累计试验次数超过百次,取得了包括井壁破坏机理的“附加力理论”在内的一系列研究成果。     

复杂水文地质下井壁受力及温度测试研究

为解决淮北矿业集团桃园煤矿新副井井筒在老工业广场冲积层中冻结法凿井的技术难题,在施工过程中对外层井壁的受力和温度进行了实时监测,获得了老工业广场内复杂地质水文条件下井壁受力和温度的实测数据,通过实测信息反馈,实现了矿井动态设计和信息化施工。     

塔什店煤矿风井冻结法施工中井壁保护技术

介绍了塔什店风井冻结施工主要的冻结参数,论述了风井温控系统的设计方法,并从大圈径布置冻结孔、异径冻结、温控孔保障等方面,提出了已成型井壁的保护措施,达到了冻结法施工中已成井壁完好无损的效果。     

外层井壁、冻结壁、泡沫板共同作用机理研究

基于粘弹性理论,建立一个适用于深厚冲积层的考虑冻结壁、外层井壁、泡沫板共同作用的粘弹性计算模型,模型中同时考虑了冻结壁的蠕变变形。导出了冻结壁黏弹性流变方程;并基于冻结壁、泡沫板和外层井壁之间的作用机理以及泡沫板压缩特性,推导出考虑泡沫板影响的辅助方程并应用于冻结壁黏弹性流变方程,从而得到冻结压力与井帮位移的关系式。     

绝热温升影响的冻结井壁温度场变化规律

为研究绝热温升对冻结井壁温度场的影响,根据井壁温度实测数据,采用ANSYS有限元分析软件对冻结壁大体积混凝土的温度场分布规律进行了数值分析,建立了考虑绝热温升影响的井壁温度场分布模型。实测与模拟结果表明:井壁浇筑后初期由于水化的热影响,井壁温度迅速升高,双曲线模型计算结果与实测值吻合程度较好。研究结果为预测冻结井壁温度场的变化规律提供了参考依据。     

深厚表土层冻结法凿井外层井壁的受力实测分析

介绍了对宁夏红四矿主井冻结井壁的冻结压力、钢筋应力、混凝土应变和温度的监测方法。通过对主井井壁的实时监测,获得已成型冻结段井壁的冻结压力、钢筋应力和混凝土应变,掌握了深部冻结井壁的钢筋轴力、混凝土应变的变化规律,在此基础上评价冻结壁和井壁的安全状况。通过实时监测,主井井壁实现了信息化施工。     

基于模糊神经网络兖州矿区立井井筒非采动破裂的判别

煤矿立井井筒非采动破裂是一种新型工程地质灾害。该灾害的发生与各影响因素之间的关系为非线性的、不确定的。本文采用模糊神经网络对其中隐藏的规律进行了提取与捕捉。经检验结果表明,通过模糊逻辑判别与人工神经网络的相结合能够很好的对立井井筒破裂灾害的发生进行判别,且结果准确可靠,能够满足实际要求。     

工程机械维修综述

本世纪机械维修行业有了巨大的发展,已经成为民国经济中的重要支柱行业。本文从现代维修的含义、维修制度、维修的组织形式、维修人员的培训、状态监测和故障诊断技术应用、工程机械维修业的发展方向以及绿色维修和再制造的概念等方面进行了简要的叙述。     

强化售后服务,打造服务品牌

当今世界,售后服务质量逐渐成为建筑行业竞争的焦点。提出服务品牌的内涵,服务品牌由服务质量、服务模式、服务技术、服务价格、服务文化、服务信誉构成。通过对建筑业企业售后服务现状的分析,阐明企业创建服务品牌的重要意义,以及实施服务品牌战略的必要性,进而提出打造服务品牌的基本策略。     

基于SERVQUAL模型的物业服务质量测评——以南京市为例

随着房地产市场的日渐成熟,物业服务质量问题已经成为企业界和学术界关注的热点问题,物业服务质量的有效测评对于提高物业企业服务水平和业主满意度具有重要的现实意义。以SERVQUAL模型为理论依据,构建了物业服务质量评价体系,并以南京市住户为研究样本,通过问卷调查的方式对物业服务质量进行测评。结果表明南京市物业服务整体水平一般;可靠性和响应性维度对物业服务质量的影响最为显著;在不同的物业档次下,物业服务质量具有显著的差异,档次越高的物业,住户对物业服务质量的整体评价也越高。最后,根据研究结论,提出改进物业服务质量的相关建议。     

Durability and the factor method of ISO 15686-1

Interest in the service life of buildings and components and the future need for maintenance is growing, and the methodology for service life planning is starting to appear in standards. The standard ISO 15686 prescribes a factor methodology for deciding about the expected service life of a component with a prescribed probability of earlier failure. The methodology is based on extensive knowledge about materials and building technology, and examples of the use of this methodology on building components are of value for the discussion on service life planning. Results from a condition survey of timber windows are used to define the service life and effect of the factor method in the Standard. Wood is a very variable material, and for wooden windows maintenance plays a key role in the durability of the component. In this instance, condition assessment is, therefore, not sufficient to estimate the service life. Information about former maintenance and refurbishment is also needed. The results from a condition assessment and the house owner's answers to a questionnaire are combined to evaluate the estimated service life of the windows. The factors for the standardized method for estimating service life with a given confidence limit are shown to have a wide range in values that give considerable uncertainty to the practical use of the standardized methodology. For example, it is shown that the estimated service life with an 80% confidence limit is much lower than the average service life. Thus, the question is posed whether there is any meaning in estimating the lower limit of service life.     

Assessing the service quality of building maintenance providers: mechanical and engineering services

This study investigates the service quality in the maintenance of mechanical and engineering services. The determinants of service quality are identified and their means of evaluation are examined. A method of assessment is devised based on the SERVQUAL approach, and its use is then illustrated using a small empirical survey of clients and service providers and the ‘Gap’ model used to quantify the relationships between customer satisfaction, expected service, perceived service and service quality gap.     

Durability and the factor method of ISO 15686-1

Interest in the service life of buildings and components and the future need for maintenance is growing, and the methodology for service life planning is starting to appear in standards. The standard ISO 15686 prescribes a factor methodology for deciding about the expected service life of a component with a prescribed probability of earlier failure. The methodology is based on extensive knowledge about materials and building technology, and examples of the use of this methodology on building components are of value for the discussion on service life planning. Results from a condition survey of timber windows are used to define the service life and effect of the factor method in the Standard. Wood is a very variable material, and for wooden windows maintenance plays a key role in the durability of the component. In this instance, condition assessment is, therefore, not sufficient to estimate the service life. Information about former maintenance and refurbishment is also needed. The results from a condition assessment and the house owner's answers to a questionnaire are combined to evaluate the estimated service life of the windows. The factors for the standardized method for estimating service life with a given confidence limit are shown to have a wide range in values that give considerable uncertainty to the practical use of the standardized methodology. For example, it is shown that the estimated service life with an 80% confidence limit is much lower than the average service life. Thus, the question is posed whether there is any meaning in estimating the lower limit of service life.     

Design-and-build contractors' service quality in public projects in Singapore

In the construction industry, total quality comprises corporate service quality, project service quality and quality of the constructed facility. This study investigates the project service quality of design-and-build (D&B) contractors when undertaking projects for public sector clients in Singapore. Service quality is operationalized into five determinants: reliability, responsiveness, assurance, empathy and tangible. From these, 34 attributes that may affect project service quality in D&B projects are identified. A questionnaire is used to ascertain clients' service quality expectations of these 34 attributes. The clients were also asked the extent to which D&B contractors achieve project service quality. It is found that D&B contractors did not meet clients' expectations in all the five dimensions of service quality. This means that D&B contractors are not giving clients the satisfaction that they hope for. This study offers D&B contractors feedback relating to clients' expectations of their service delivery and the areas of service that need to be improved in order to provide quality service that will satisfy public sector clients.     

Impact of Urban Public Service Facilities on Distribution Pattern of Housing Price

The impact of different public service facilities is obtained by investigating the influence of public service facilities on distribution pattern of housing price in 25 cities.According to the survey results,public education service facilities have the highest weight and the greatest impact,which also reflects the root of "school district housing fever" from the side.Public sports service facilities have the lowest score when compared with other options.This is not because public sports service facilities are not important,but is determined by actual situation of social development and actual living standard of residents in China.From the improvement and enhancement of urban public service facilities,the construction of public service facilities should be convenient for people’s education,health,culture and entertainment.     

工程建设监理的诚信服务

监理是高智能服务 ,诚信是监理的行为准则之一 ,介绍了当前监理企业诚信服务的影响因素 ,对监理企业的诚信服务提出几点意见 ,指出工程监理企业在实际工作中做到诚信服务对企业健康发展的促进作用