外文翻译---高层建筑施工的控制要点.docx

文献翻译High-rise building construction control pointsconstruction process. Data statistics show Ruoyin increase the moisture content of sand, sand rate fell 2% to 3%, concrete strength will be decreased by 15% to 20%, while the quantity of cement and 5% to 20%, gravel and sands affect 5% to 20%; water-cement ratio affect more by l%, 5% strength of a 10% reduction. Since the impact so great, it should take appropriate measures to control. (1) According to the regional market conditions for different proportions of raw materials testing, construction process to ensure the timely adjustment of the ratio, such as 5 40mm stones, M 2.3 fine sand to do a ,5-40mm gravel, M 2.3 in the sand to do a set of so. (2) the ratio of combination of laboratory water content of raw materials, for construction with mud content ratio adjusted to ensure that the ratio of the actual laboratory versatility. In the actual construction work to strengthen the checks of raw materials, sand and gravel gradation bad, take appropriate measures to adjust, such as the amount of incorporation of 0.5? L 10? L sand and gravel.2.2 The strict conservation system By pumping concrete high-rise building and more. Pumping concrete can not only shorten the construction period, but also to improve the performance of concrete construction. However, the use of certain projects that the ratio of raw materials, vibration control strictly the case, there is still lack of concrete strength. Ana1 Introduction With the vigorous development of Chinas economy, building science and construction technology has been developing rapidly. Especially in urban areas, with land full of tension and further the comprehensive utilization of land, high-rise buildings are increasingly becoming the main urban construction. In general, 9 16 layers (50m) for a class of high-level, 17 to 25 layers (75m) for the second category level, 26 to 40 layers ( 40 layer ( 100m) for the super-class level. As the multi-storey high-rise buildings into relatively large, and long construction period, large amount of concrete pouring, construction quality and safety, has its particularity, the author further enhance the quality and ensure the safety point of view, combined with some experience in practice , my personal views. 2, the intensity of high-rise building control Strength mainly refers to the strength of concrete. As the large amount of high-rise buildings of concrete and long construction period, impact of climate and working conditions of many factors, sometimes discrete, a concrete strength, and even failure. So how to overcome and control the strength of the concrete well off?2.1 ratio of the selected Project started before the general design requirements are formulated according to different strength grade of concrete, and have to do statutory testing agencies graded test, after the report to be graded, according to grading to do with the ratio test (laboratory ratio), do the same in the actual construction of the implementation. But the problem is with the site grading is consistent with the lysis of the reasons, mostly for looting period, a serious shortage of curing time. According to experts, the test results, the strength of conservation than all wet 28 days: 3 days is all wet conservation: conservation of the air were 2:1.5:1 28d. This shows the importance of conservation. (1) of the large volume of concrete should be poured large conservation programs, from the beginning to the conservation of the end of the conservation should be responsible, from the subjective consciousness and conservation should have sufficient knowledge. Conservation programs should be personnel, water, day and night, covering measures to consider other aspects, does not leak key details. (2) to strengthen the conservation of the inspection. Conservation measures taken and the situation on site maintenance track record of timely detection of problems and ensure the effectiveness of conservation.2.3 Reinforced Concrete Strength Evaluation Excluding the non-standard test block production of the phenomenon. When the strength of concrete block design strength test than when it is the strength assessment is good? Not really. Concrete Strength Testing Standards (GBJ107) provides concrete strength inspection and evaluation should be conducted in batches. An acceptance by the strength grade of concrete batch the same age and the production of the same process conditions and the same proportion of the concrete composition.Choose one according to the appropriate conditions, all of which relate to a standard deviation of the problem. As the cycle of high-rise building construction, concrete pouring and curing such a large difference in climatic conditions, concrete tests have greater dispersion of values, that is the standard deviation is too large, such as generally judged as a group, are likely to fail and should therefore be divided approved, according to the same conditions of the designated group were assessed, this is consistent with national regulatory requirements, in line with the actual scene.3 high-rise building three-wire controlAxis, elevation, vertical meridian degree similar to buildings. High-rise buildings, because covers a wide range, the operation is difficult, often in the phenomenon of displacement or not allowed. Three line control is a major high-rise building difficult.3.1 Control of verticality (1) control the vertical degree is the foundation to ensure the quality of high-rise building is one of the key links. In order to control the verticality of the building construction, the first column should be based on building network layout situation, first building to determine the location of the four corner columns. The installation of four corner columns template, pop up along the thickness of the outer column line, vertical mode, plus support line was determined by hanging the vertical column degree: 100% in ensuring verticality, the aligned template support outside line reinforcement , pouring of concrete. When four prism form removal, the other columns to the four columns for the baseline columns, brace wire, positive control flatness and straightness. (2) the vertical degree of control during the application of double laser plus heavy hammer for more experience, so adding more vertical degree of accuracy, while with the inner and outer pair of vertical control to high-rise buildings can reduce investment and measurement errors to a minimum. 3.2 Axis Control (1) axis passes. High-rise building construction process, the scaffolding and construction layer sync up, leading to a number of reference points from the external measurements can not be cited. Therefore, the structure in the construction of 0.00, after review and correct axis to - floor as the base layer in the maximum vertical and horizontal to the embedded multi-block 200 * 200 * 8mm steel plate, the plate marked on the control of axis or main axis of control points: 2 layer and above construction to the floor as the base layer corresponding position on each floor to remain set 200 * 200mm square hole, using a large line of Hammer cited the lower floor of the control points measured, then axis of theodolite and steel tape measure to correct , release layers, and detailed dimension axis line. (2) the control of the process line. Hang two lines, pouring a good wall, which is the key to the process line control. Pouring wall, it is appropriate to 18mm thick high-quality laminated plywood, a large-scale fixed combination of outer walls, interior demolition combination of bulk dispersion model number. This wall roughness is guaranteed, but we must note that the verticality of the wall. To do this: template support wall when the strict control of the four corners, four corners of the vertical to ensure a minimum degree of deviation within: when pouring coagulation, the wall outside the plane of the waist and the top of the hanging wire to ensure that line and the template is always consistent, timely adjustment problems are identified, so as to achieve linear control. 3.3 elevation control line (1) Pre-control axis in each layer at least four holes (generally top up by at least three cited measure) for elevation of the location, supplemented by the sum of multi-level review, and then supplemented with water level copy level, review the 4:00 is in the same horizontal plane to ensure the accuracy of elevation. (2) elevation of which of the four holes required to improve the accuracy of their own, because of the construction process template, casting, loading and other reasons, the hole may lose benchmark elevation effect. So we must ensure the reliability of the measuring point lead, strengthen the exit of the hole template support, supplemented by a diameter of 12 steel control the thickness of the floor area to ensure the accuracy of elevation. (3) in the building corners, surrounded by the conditions set-storey office, review the cumulative story points up on each floor are attached to the position review, to prevent the accumulated error is too large. Level elevation of the review process must achieve each level of the four-storey entrance control points and review points outside the horizontal plane before being confirmed at the same level of accuracy, to achieve elevation control. (4) Building Crack ControlFrom our concrete with structural design specification GB50010-2002 Table 3.3.4 shows that crack width in a different environment, different structure of the crack width of concrete have different control standards, allowing a maximum of 0.2mm crack 0.4? L. But as for crack control should be the main pre-control, and so broken up, and slit increases the longer it is a last resort remedy. Cracks into motion, unstable, stable, closed, several major types of healing. While aggregate production within the solidification micro-cracks is inevitable, but from the point of view of quality should be minimized. As the strength of concrete high-rise buildings generally high, concrete in large quantities, and with a basement, it cracks more likely. The following description of the principal on crack open, anti relevant measures.The so-called put is the free deformation of the structure completely unconstrained state, when there is enough room for deformation of the measures taken by; so-called anti is in a bound state, the structure of the deformation in the room when there is not enough to prevent cracks measures taken. 高层建筑施工的控制要点1.引言 随着我国社会经济的蓬勃发展，建筑科学和建筑技术也有了高速发展。尤其在城市，随着土地的紧张及进一步充分发挥土地的综合利用率，高层建筑正在日益成为城市建设的主体。一般而言，916层(50m)为一类高层，1725层(75m)为二类高层，2640层(40层(100m)为超类高层。由于高层建筑的投入相对多层大，且施工周期长，混凝土浇筑量大，工程质量及安全等方面有它的特殊性，笔者从进一步加强质量及确保安全角度出发，结合在实践中的一些体会，谈谈个人的一些看法。2. 高层建筑的强度控制 强度主要是指混凝土的强度。高层建筑由于混凝土用量大，施工周期长，气候及工作条件影响因素多，有时会发生混凝土强度离散性大，甚至不合格。那么如何克服和控制好混凝土的强度这一关呢?21配比的选定 工程开工前，一般均要按设计要求配制不同强度等级的混凝土，并都要到法定试验机构做级配试验，待级配报告出来后，根据级配做配合比试验(实验室配比)，在实际施工时照此执行。但问题就在于级配与现场施工过程中是否相符。有资料统计显示，若因砂的含水率增多，砂率下降2一3，混凝土强度将下降1520，而水泥数量的影响为520，石子及砂的级配影响为520；水灰比影响为多增l，强度降低5一10。既然影响如此之大，那就应该采取相应措施进行控制。 （1）根据地区市场原材料情况进行不同配比的试验，以确保在施工过程中配比的及时调整，如540mm石子，M2.3细砂做一组，540mm石子，M2.3中粗砂做一组等等。 （2）对实验室配比结合原材料的含水量、含泥量进行施工配合比调整，以确保实验室配比的实际通用性。在实际施工中要加强原材料把关工作，沙石级配不良时，采取相应措施调整，如适量掺入0.5?L10?L沙石等。22严格养护制度 高层建筑多采用泵送混凝土。泵送混凝土不仅能缩短施工周期，而且能改善混凝土的施工性能。但在某些工程上的使用表明，在配比、原材料、振捣控制严格的情况下，仍出现混凝土强度不足。分析其原因，多为抢工期、养护时间严重不足。据有关专家测试结果，其强度比全湿养护28天全湿养护3天：空气中养护28d分别为2：15：1。由此可见养护的重要性。 (1)对大体积浇筑量大的混凝土应有养护方案，从养护开始至养护结束应有专人负责，从主观意识上要对养护有足够的认识。养护方案中应从人员、水源、昼夜、覆盖等多方面措施进行考虑，不漏主要关键细节。 (2)加强养护期的督查。对养护所采取的措施及现场养护情况进行跟踪记录，及时发现问题，确保养护的有效性。23加强混凝土强度评定 剔除试块制作的不规范现象。当混凝土试块的强度测试大于设计强度时，是否就是强度评定合格了呢?不尽然。混凝土强度检验评定标准(GBJ107)规定，混凝土强度应分批进行检验评定。一个验收批的混凝土应由强度等级相同、龄期相同以及生产工艺条件和配比基本相同的混凝土组成。 根据相应条件选定一种，这其中都涉及到一个标准差问题。高层建筑由于施工周期、混凝土的浇筑、养护等气候条件相差大，混凝土试验值的离散性也较大，即标准差过大，如笼统地作为一批来评定，很可能不合格，因此应分批，按条件基本相同的划为一批进行评定，这样做既符合国家规范要求，也符合现场实际。3. 高层建筑“三线”控制 轴线、标高、垂直度类似于建筑物的经络。对高层建筑来说，由于涉及面广，操作难度大，经常会发生位移或不准现象。“三线”的控制是高层建筑的一大难点。31垂直度的控制 (1)控制垂直