质量控制和安全施工外文翻译.doc

本文献来源于：1 董祥. 土木工程英语. 2010（9）：145-151质量控制和安全施工1在施工中存在的质量和安全问题质量控制和安全问题对项目经理来说变得越来越重要。施工过程中的设备缺陷或故障可能会导致非常大的成本。即使有轻微缺陷, 也可能需要重新建设使设施运营受损。导致成本的增加和延误结果。在最坏的情况下，故障可能导致人身伤害甚至死亡。在施工过程中的事故可能导致人身伤害和巨大的花费。保险，检验和监管的间接成本迅速增加，会导致直接成本的增加。好的项目经理应尽量确保在第一时间完成任务，并且在工程中没有重大事故发生。随着成本的控制，关于已完成设施的质量的最重要的决策是在设计和规划阶段，而不是在施工阶段。正是在该组件的配置，材料规格和功能性能这些初步阶段而决定的。施工过程中的质量控制主要是确保其是否符合原先的设计和规划决策。虽然符合现有的设计决策是质量控制的首要重点，但也有例外的情况。第一，不可预见的情况下，错误的设计决策或希望通过在设备功能的所有者权益变动，可能在施工过程中要求对设计决策进行重新评估。虽然这些变化可能是出于关心质量，但他们意味着随之而来的所有目标和限制因素都要进行重新设计。至于第二种情况，一些明智且适当的设计决策就是取决于施工过程本身，例如，一些隧道要求在不同的位置作出一定数量支护的方法，就是根据土壤条件，观察在隧道里面的过程而做出的决策。由于这样的决定是基于有关工地的实际情况，因此该设施的设计可能会更符合成本效益的结果。任何特殊的情况下，重新设计的施工过程中都需要考虑各种因素。在施工过程中以讲究一致性作为质量的衡量标准，质量要求的设计和合同文件中的说明将变得极为重要。质量要求应该是明确的、可验证的，能使项目中的各方都能够理解的一致性要求。本章的大部分讨论均涉及到发展和建设的不同质量要求，以及确保符合性的相关问题。建设项目中的安全性也在很大程度上影响到规划设计过程中的决策。一些设计或施工计划本身就是又危险又很难实现的，而其他类似的计划，则可以大大降低事故发生的可能性。例如，从施工区域内修复巷道使得交通分道行驶可以大大降低意外碰撞的可能性。除了这些设计决策，在施工过程中安全在很大程度上取决于教育，提高警惕，合作。工人应对可能发生意外保持时刻警惕，避免不必要的风险。2组织的质量和安全在施工过程中，各种不同的组织均可对质量和安全进行控制。一个常见的模式是由一个组负责质量保证而另一个组则主要负责集团内的安全组织。在大型的组织中，各部门致力于确保质量和安全，可能会指定专人来承担这些具体项目的责任。对于较小的项目，项目经理或助理可能会承担相应责任。在任一情况下，确保安全和质量建设是项目经理在除人事、成本、时间和其他管理问题以外必须重点关注并全面负责的。检查人员和质量保证人员将代表各种不同的组织共同参与一个项目。跟项目直接相关的各方都可能有自己的质量和安全检查，包括业主，工程师/设计师，和各种构造公司。这些检查员可以从专业的质量保证机构组织选择担任。除了现场检查，材料样品通常会由专门的实验室测试，以确保其权威性。为了保证符合监管要求，相关部门也将参与其中。常见的例子是当地政府建设部门的督察，环境机构，和职业健康与安全机构。美国职业安全与健康管理局（OSHA）与获批准的国家检验机构合作，定期对工作场所进行实地考察。OSHA的检查人员必须依法对所有违背标准的行为进行采证。以保障安全标准规定的各种机械措施和程序; 例如，梯子的安全有超过140个法规。在极端不符合标准上面法规的情况下，安全检查员可以停止在一个项目的工作。然而，只有一小部分的建筑工地是由OSHA督察巡视的，大多数施工现场的事故并非由违反现有标准造成的。因此，安全问题在很大程度上应由现场管理人员而非公共督察负责。而施工过程中的众多参与者都需要检查人员的服务，也不能过于强调检查人员只检查质量控制的过程。好的质量控制应该是一个项目团队所有成员的首要目标。管理者应承担维护和提高质量控制的责任。员工参与质量控制包括引入了新的思路都应该被奖励。最重要的是，质量改进可以作为提高生产率的催化剂。良好的质量控制可以通过提出新的工作方法，避免返工，并避免长期的问题，达到自给自足。业主应促进良好的质量控制，并寻求能保持这样的水准的承包商。除了参与质量控制的各种组织机构，质量控制问题在几乎所有的建筑活动功能区均出现过。例如，确保准确和有用的信息是保持质量性能的重要组成部分。质量控制的其他方面包括文件控制（包括在施工过程中的变更），采购，现场检查和测试，以及设施的竣工验收。3工作和材料规范工作质量的规格是设备设计的一个重要特性。要求的质量和部件的规格代表了必要的文件来描述一个设备的一部分。通常情况下，这个文件包含了施工期间使用的设备设计文件和公认的规范的任何特殊规定，作为参考。工作质量一般规格在许多领域都是在如美国材料与试验协会（ASTM），美国国家标准协会（ANSI），或施工规范协会（CSI）等组织的刊物上发表。不同规格的形式为特定类型的建设活动，如由美国焊接协会颁发的焊接标准，或特定设施的类型，如由美国协会的国家公路和运输官员颁发的公路桥梁的标准规范。这些一般规格必须进行修改，以反映当地的条件，政策，提供的材料，地方性法规及其他特殊情况。施工规范通常由一系列的具体操作指令或禁令组成。例如，下面的文章说明了一个典型的对在这种情况下的挖掘结构的规范：符合标高和尺寸正负0.10英尺的容差范围内的计划显示，从地基和基础延伸足够的距离，允许放置及拆除混凝土模板，安装服务，其他建筑，并进行检查。在挖掘挖掘地基和基础时，当心别影响基坑开挖。用手挖掘并最终分级来填置钢筋混凝土。调整（挖掘的）最底层到需要的路线和坡度，留下坚实的基础去填充坚实（的混凝土）。这一组规范要求应用判断，是由于有些项目不能精确地指定。例如，开挖必须延长“足够”的距离，以便进行检查和其他活动。显然，“足够”这个词，在这种情况下，可能会受到不同的解释。相反，一个规范，公差内加或减十分之一英尺则是直接测量。然而，由于网站的设施或特征的具体要求， 可能会使得十分之一英尺的标准公差变得不合适。书写规范通常需要在假设有关各方在诸如“充足”与预指定所有操作的努力和可能的解释不准确的话双方的部分合理的行为之间的权衡。近年来，性能规格已经被开发运用于许多施工作业。这些规范是指所要求的性能的成品设施或质量，而不是指定所需的施工过程中的规范。而如何从其中获得此性能的具体方法则是留给建筑承包商的。例如，传统规格为沥青路面中指定的沥青材料，沥青组合物的摊铺温度，压实过程。相反，一个性能规格沥青所需的详细性能是关于路面的抗渗性及强度等。如何达到所期望的性能水平则要依靠铺路承包商。质量控制（）1全面的质量控制在施工质量控制一般包括投保符合材料和工艺上最低准则，以便根据设计，以确保设备的性能。这些最低标准都包含在上一节中描述的规范。对于符合保险的目的，随机抽样和统计方法通常用于为基础，接受或拒绝工作完成，材料批次。一批拒绝是基于不符合或违反有关设计规范。这种质量控制的实践过程在下面的章节中描述。在这些传统的质量控制方法的一个隐含的假设是可以接受的质量水平，这是不良品的允许分数的概念。由一个组织进行供应商或工作组获得的材料进行检查，如果估计有缺陷，但是所占百分比是在可接受的质量水平，让供应商和工作组来判断判断是否通过验收。如果是材料或货物的问题则是在产品交付后校正。与此相反，质量控制这种传统的方法是全面质量管理的目标。在这个系统中，施工过程中的任何地方都不允许有次品。而完美的目标却是永远无法达到的，它提供了一个目标，让组织永远不会满足于它的质量控制程序，使得缺陷在年复一年的大量减少。这个概念和质量控制的方法最初是开发制造在日本和欧洲的公司，但已蔓延到许多建筑公司。最有名的质量改进的正式认证是国际标准化组织ISO9000标准。ISO 9000强调良好的文档，质量目标和一系列的周期规划，实施和审查。全面质量管理是一个对质量的承诺，表现在组织的各个部分，通常涉及许多元素。设计审查是确保安全和有效的施工程序的一个主要元素。其他因素包括大量的人员培训，转移检测产品缺陷的质量控制员的责任，并不断维护设备。在质量圈中的工人小组定期开会，提出质量改进的建议，但工人参与改进质量控制往往是形式化的。材料供应商也需要确保交付货物的零缺陷。首先，从供应商的所有材料进行检查，有缺陷的商品被分批次退回。能证明自己信誉优良的供应商，则可以在之后完成检查。质量控制的传统微观经济学的观点是有缺陷的项目的“最优”的比例。努力实现比这更大的最佳的质量会大幅增加检验成本，降低员工的工作效率。然而，许多公司都发现，致力于全面质量控制可以产生可观的经济效益，这是一个曾经一直不受重视的传统方法。全面质量控制使得返工，废钢和保证与库存相关费用均减少，并且改善工作人员的积极性和工作决心。客户往往喜欢更高质量的作品，并会为其高质量支付高价。其结果是，完善的质量控制成为了一个竞争优势。当然，全面的质量控制是很难应用的，尤其是在建设中。各设施的独特性，劳动力的变化性，众多分包商，教育和程序进行必要的成本投资，使项目全面质量控制的实施难度大。然而，一个组织虽不能保证达到完美的目标但却一直致力于提高质量，那么它可以是一个真正为大家造福的组织。附外文原文：Quality Control and Safety during Construction1 Quality and Safety Concerns in ConstructionQuality control and safety represent increasingly important concerns for project managers. Defects or failures in constructed facilities can result in very large costs. Even with minor defects，re-construction may be required and facility operations impaired. Increased costs and delays are the result. In the worst case, failures may cause personal injuries or fatalities. Accidents during the construction process can similarly result in personal injuries and large costs. Indirect costs of insurance, inspection and regulation are increasing rapidly due to these increased direct costs. Good project managers try to ensure that the job is done right the first time and that no major accidents occur on the project.As with cost control, the most important decisions regarding the quality of a completed facility are made during the design and planning stages rather than during construction. It is during these preliminary stages that component configurations, material specifications and functional performance are decided. Quality control during construction consists largely of insuring conformance to these original designs and planning decisions.While conformance to existing design decisions is the primary focus of quality control, there are exceptions to this rule. First, unforeseen circumstances, incorrect design decisions or changes desired by an owner in the facility function may require re-evaluation of design decisions during the course of construction. While these changes may be motivated by the concern for quality, they represent occasions for re-design with all the attendant objectives and constraints. As a second case, some designs rely upon informed and appropriate decision making during the construction process itself. For example, some tunneling methods make decisions about the amount of shoring required at different locations based upon observation of soil conditions during the tunneling process. Since such decisions are based on better information concerning actual site conditions, the facility design may be more cost effective as a result. Any special case of re-design during construction requires the various considerations.With the attention to conformance as the measure of quality during the construction process, the specification of quality requirements in the design and contract documentation becomes extremely important. Quality requirements should be clear and verifiable, so that all parties in the project can understand the requirements for conformance. Much of the discussion in this chapter relates to the development and the implications of different quality requirements for construction as well as the issues associated with insuring conformance.Safety during the construction project is also influenced in large part by decisions made during the planning and design process. Some designs or construction plans are inherently difficult and dangerous to implement, whereas other, comparable plans may considerably reduce the possibility of accidents. For example, clear separation of traffic from construction zones during roadway rehabilitation can greatly reduce the possibility of accidental collisions. Beyond these design decisions, safety largely depends upon education, vigilance and cooperation during the construction process. Workers should be constantly alert to the possibilities of accidents and avoid taken unnecessary risks.2 Organizing for Quality and SafetyA variety of different organizations are possible for quality and safety control during construction. One common model is to have a group responsible for quality assurance and another group primarily responsible for safety within an organization. In large organizations, department dedicated to quality assurance and to safety might assign specific individuals to assume responsibility for these functions on particular projects. For smaller projects, the project manager or an assistant might assume these and other responsibilities. In either case, insuring safe and quality construction is a concern of the project manager in overall charge of the project in addition to the concerns of personnel, cost, time and other management issues.Inspectors and quality assurance personnel will be involved in a project to represent a variety of different organizations. Each of the parties directly concerned with the project may have their own quality and safety inspectors, including the owner, the engineer/architect, and the various constructor firms. These inspectors may be contractors from specialized quality assurance organizations. In addition to on-site inspections, samples of materials will commonly be tested by specialized laboratories to insure compliance. Inspectors to insure compliance with regulatory requirements will also be involved. Common examples are inspectors for the local governments building department, for environmental agencies, and for occupational health and safety agencies.The US Occupational Safety and Health Administration (OSHA) routinely conduct site visits of work places in conjunction with approved state inspection agencies. OSHA inspectors are required by law to issue citations for all standard violations observed. Safety standards prescribe a variety of mechanical safeguards and procedures; for example, ladder safety is covered by over 140 regulations. In cases of extreme non-compliance with standards, OSHA inspectors can stop work on a project. However, only a small fraction of construction sites are visited by OSHA inspectors and most construction site accidents are not caused by violations of existing standards. As a result, safety is largely the responsibility of the managers on site rather than that of public inspectors.While the multitude of participants involved in the construction process require the services of inspectors, it cannot be emphasized too strongly that inspectors are only a formal check on quality control. Quality control should be a primary objective for all the members of a project team. Managers should take responsibility for maintaining and improving quality control. Employee participation in quality control should be sought and rewarded, including the introduction of new ideas. Most important of all, quality improvement can serve as a catalyst for improved productivity. By suggesting new work methods, by avoiding rework, and by avoiding long term problems, good quality control can pay for itself. Owners should promote good quality control and seek out contractors who maintain such standards.In addition to the various organizational bodies involved in quality control, issues of quality control arise in virtually all the functional areas of construction activities. For example, insuring accurate and useful information is an important part of maintaining quality performance. Other aspects of quality control include document control (including changes during the construction process), procurement, field inspection and testing, and final checkout of the facility.3 Work and Material SpecificationsSpecifications of work quality are an important feature of facility designs. Specifications of required quality and components represent part of the necessary documentation to describe a facility. Typically, this documentation includes any special provisions of the facility design as well as references to generally accepted specifications to be used during construction.General specifications of work quality are available in numerous fields and are issued in publications of organizations such as the American Society for Testing and Materials (ASTM), the American National Standards Institute (ANSI), or the Construction Specifications Institute (CSI).Distinct specifications are formalized for particular types of construction activities, such as welding standards issued by the American Welding Society, or for particular facility types, such as the Standard Specifications for Highway Bridges issued by the American Association of State Highway and Transportation Officials. These general specifications must be modified to reflect local conditions, policies, available materials, local regulations and other special circumstances.Construction specifications normally consist of a series of instructions or prohibitions for specific operations. For example, the following passage illustrates a typical specification, in this case for excavation for structures:Conform to elevations and dimensions shown on plan within a tolerance of plus or minus 0.10 foot, and extending a sufficient distance from footings and foundations to permit placing and removal of concrete formwork, installation of services, other construction, and for inspection. In excavating for footings and foundations, take care not to disturb bottom of excavation. Excavate by hand to final grade just before concrete reinforcement is placed. Trim bottoms to required lines and grades to leave solid base to receive concrete.This set of specifications requires judgment in application since some items are not precisely specified. For example, excavation must extend a sufficient distance to permit inspection and other activities. Obviously, the term sufficient in this case may be subject to varying interpretations. In contrast, a specification that tolerances are within plus or minus a tenth of a foot is subject to direct measurement. However, specific requirements of the facility or characteristics of the site may make the standard tolerance of a tenth of a foot inappropriate. Writing specifications typically requires a trade-off between assuming reasonable behavior on the part of all the parties concerned in interpreting words such as sufficient versus the effort and possible inaccuracy in pre-specifying all operations.In recent years, performance specifications have been developed for many construction operations. Rather than specifying the required construction process, these specifications refer to the required performance or quality of the finished facility. The exact method by which this performance is obtained is left to the construction contractor. For example, traditional specifications for asphalt pavement specified the composition of the asphalt material, the asphalt temperature during paving, and compacting procedures. In contrast, a performance specification for asphalt would detail the desired performance of the pavement with respect to impermeability, strength, etc. How the desired performance level was attained would be up to the paving contractor. In some cases, the payment for asphalt paving might increase with better quality of asphalt beyond some minimum level of performance.Quality Control ()1 Total Quality ControlQuality control in construction typically involves insuring compliance with minimum standards of material and workmanship in order to insure the performance of