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首页> 外文会议>Association of State Dam Safety Officials, Inc. 2002 Annual Conference Sep 8-11, 2002 Tampa, Florida >RCC TESTS, TESTING, AND TEST SECTIONS - LESSONS LEARNED
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RCC TESTS, TESTING, AND TEST SECTIONS - LESSONS LEARNED

机译：RCC测试，测试和测试部分-经验教训

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摘要

The use of roller-compacted concrete (RCC) to rehabilitate existing dams and build new dams is now more than two decades old. Since its introduction, RCC has become a powerful tool to dam safety design engineers. The use of RCC to provide overtopping protection for existing embankment dams has now passed the 70 projects mark and another dozen old concrete or masonry dams have been buttressed using RCC. In addition, about 25% of the 65 new RCC gravity dams built in the United States to date have replaced failed, poorly performing or structurally inadequate existing dams. Nearly all of the dams that required replacement were older embankment dams. In order to properly provide quality control to the RCC being produced and placed, tests were needed to assure that the specified mixture proportions were being produced, the RCC had the desired consistency and had been compacted to a required minimum density. In addition, RCC test specimens needed to be prepared that produced properties similar to those achieved in the actual project. It soon became apparent that some test methods that had been used for conventional slump concrete or in some cases for soils could be used for RCC. However, some new test methods needed to be developed for RCC that were unique to the no-slump consistency of the material. In the development of new test methods for RCC construction, much has been learned. Some tests that were used early in this development have fallen out of favor while some continue to be used. However, some of the test standards that were accepted earlier need modification and some only have a certain range of applicability depending upon the consistency of the RCC mixture. Another important factor in quality control for RCC is the test section or trial placement. This is because many contractors or their key personnel are not very familiar with RCC construction or the specific requirements of the project. Again, much has been learned about the design and execution of test sections in order to obtain the greatest benefit for the cost involved.
机译：现在，使用碾压混凝土（RCC）修复现有的水坝并建造新的水坝已有20多年的历史了。自推出以来，RCC已成为大坝安全设计工程师的强大工具。使用碾压混凝土为现有的堤坝提供过高保护，现在已经超过了70个项目大关，另外十多个使用碾压混凝土的混凝土或砖石水坝得到了支撑。此外，迄今为止，在美国建造的65座新RCC重力水坝中，约有25％已更换失败，性能不佳或结构上不充分的现有水坝。几乎所有需要更换的水坝都是较旧的堤坝。为了适当地控制所生产和放置的RCC的质量，需要进行测试以确保所生产的指定混合物比例，RCC具有所需的稠度并已压实至所需的最小密度。另外，需要准备RCC测试样品，其产生的特性与实际项目中获得的特性相似。很快变得很明显，可以将用于常规坍落度混凝土或某些情况下用于土壤的某些测试方法用于RCC。但是，需要为RCC开发一些新的测试方法，这些方法对于材料的无坍落度一致性是独一无二的。在开发用于RCC的新测试方法中，已经学到了很多。在此开发过程的早期使用的某些测试已不受欢迎，而有些则继续使用。但是，某些早先接受的测试标准需要修改，而有些仅根据RCC混合物的稠度具有一定的适用范围。 RCC质量控制中的另一个重要因素是测试部分或试验放置。这是因为许多承包商或其关键人员对RCC建设或项目的特定要求不是很熟悉。再次，关于测试部分的设计和执行已经学到了很多东西，以便从所涉及的成本中获得最大的收益。

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