人们一直都在寻找更经济节约且更环境友好的方法。近日，北卡罗莱纳州立大学的一个研究小组就发现了一个建设如停车场这样的大规模建筑时既省钱又环保的方法。
具体地说，研究人员已经找到了一个在不牺牲安全性的同时，少用30%的钢筋制造停车场用混凝土梁的方法，该研究小组的领导人之一Sami Rizkalla博士表示，他们开发的设计准则可以使用更少的钢筋，同时保持安全性和可靠性。Rizkalla博士说，新拱肩设计“简化了预制混凝土生产商的施工”。 除了使用较少钢外，新的设计削减了一半的劳动力和生产时间，显着地降低了成本。
北卡罗莱纳州立大学的博士生Greg Lucier也在这项研究中担任重要工作，他说，这项新的设计准则是包括一定的安全幅度的。例如，Lucier说，这个拱肩可以承受比我们预期能承受的最大重量还要大2到3倍的重量。Lucier还是北卡罗莱纳州建筑设施实验室的实验室负责人， Lucier也是经理数控国家，该实验室监督新拱肩设计测试。
图片：Sami Rizkalla博士解释说，通过测试新的混凝土梁的设计，看它可以承重多少，研究人员已经确定，它的承重比预期的最大承重还要大2至3倍
新设计准则源自一个2007年1月发起的为期两年的项目，该项目由预制/预应力混凝土协会（PCI）支持。PCI 为整个项目提供北卡罗莱纳州超过40万美元的资金、物资和技术支持，
该项目的成功已经引起混凝土行业的兴趣，个别公司来北卡罗莱纳州了解如何改进自己的产品和制造工艺。例如，Rizkalla说，很多公司希望与建筑设施实验室的研究人员合作，研究开发项目相关的新材料，如可用于混凝土产品的先进的复合材料。
研究人员已经公布了研究项目的一些内容，他们还将对整个项目进行概述，包括新的测试数据，这些将在六月份在圣安东尼奥举行的美国混凝土协会春季大会上首次公布。
附英文：
New Precast design means cheaper, more sustainable construction
(North Carolina) -- People are always looking for ways to make something less expensive and more environmentally friendly – and a team of researchers from North Carolina State University has figured out how to do both of those things at once when raising the large-scale buildings, such as parking garages, of the future.
More specifically, the researchers have figured out a way to use 30 percent less reinforcing steel in the manufacture of the concrete beams, or spandrels, used in the construction of parking garages – without sacrificing safety. Dr. Sami Rizkalla, one of the leaders of the research team, says they developed design guidelines that use less steel while maintaining safety and reliability. The new spandrel design "simplifies construction for precast concrete producers," Rizkalla says. In addition to using less steel, the new design cuts labor and manufacturing time in half – significantly decreasing costs.
Greg Lucier, a doctoral student at NC State who was also crucial to the research effort, says the new design guidelines include a significant margin for safety. For example, Lucier says the spandrels could handle two to three times the maximum weight they would be expected to bear. Lucier is also the lab manager of the Constructed Facilities Laboratory at NC State, which oversaw the testing of the new spandrel design.
The new design guidelines stem from a two-year project that was launched in January 2007, with support from the Precast/Prestressed Concrete Institute (PCI). PCI provided NC State with more than $400,000 in funding, materials and technical support over the life of the project.
The success of the project is already drawing interest from the concrete industry, with individual companies coming to NC State to get input on how to improve their products and manufacturing processes. For example, Rizkalla says, many companies want to collaborate with researchers at the Constructed Facilities Laboratory on research and development projects related to new materials, such as advanced composites, to be used in concrete products.
While researchers have published some elements of the research project, they will present an overview of the entire project – including new testing data – for the first time at the spring convention of the American Concrete Institute in San Antonio this month.
