神马文学网美科研人员造出新型抗地震建筑
来源：百度文库 编辑：神马文学网 时间：2024/04/28 13:35:58
研究人员在实验室里模拟地震。
网易探索3月11日 美国密歇根大学的研究人员在实验室里模拟了一场地震，用来测试他们一项令人鼓舞的新技术，这项技术被用在那些高大的混凝土建筑上。测试非常成功，这些建筑承受住了比在地震中更多的震动。工程师使用了光纤钢筋的混凝土，用来制造一种更好的并联梁。这种并联梁只需要较少的钢筋，并且很容易建造。并联梁连接了墙壁和大楼周围的通道，例如那些留给门窗和电梯的空间。这些通道是不可缺少的，但却会降低墙壁的牢固度。James Wight说：“我们模拟了一场地震，这场地震超越了可能发生的最大地震的范围。然而我们的实验试还是非常成功。我们的光纤钢筋混凝土梁的表现和我们对它的预期一样，它比现今使用的建筑横梁要好得多。”James Wight是密歇根大学土木与环境工程部门的大学教授。在这个工程上，和Wight一起工作的还有Gustavo Parra-Montesinos和Remy Lequesne，他们分别是密歇根大学土木与环境工程的副教授和博士生。现在，并联梁不仅非常难安装，还要求复杂的钢筋骨架来支撑。密歇根大学的工程师制造了一种更加简单的骨架，由高度流动的光纤钢筋混凝土构成。“我们把那些笨重的钢筋排除在设计之外，取而代之的是光纤钢铁，当它被混合的时候它能够加到混凝土里，”Parra-Montesinos说。“施工人员可以用这个光纤钢铁混凝土来建造并联梁，并且不需要那么多笨重的钢筋。”工程师们预计他们的横梁品牌将投向建筑业然后投产。如今，在施工人员一点一点的建设摩天楼时，他们可以建造横梁，钢筋骨架和所有的东西。他们的光纤钢筋混凝土还有别的好处。Parra-Montesinos说：“光纤钢筋混凝土梁只会发生很小的裂缝，因为光纤把他们聚集在一起。”那些光纤大概只有1英尺长，一根针那么宽。在08年的12月，通过一个在建筑实验室里建造的4面墙的楼房，工程师们在演示了他们的测试。他们在这个楼房上采用了极端的负荷300，000磅，用液压制动器对楼房进行反复的推拉。为了对结果进行量化，工程师们通过对比大楼顶部与地基的运动，测量了建筑物的位移程度。在大地震中，一般的楼房可能支撑百分之一到百分之二的位移，但是“密歇根建筑”很轻松就支撑了百分之三的位移。在地震的多发地带，这种新的横梁将提供更加容易、更加便宜、更加牢固的方法来支撑建筑物。研究人员现在正同一家结构设计公司合作，在各个高层建筑上安装这种新的横梁，不久也将在美国西部海岸建设。这项研究是由美国国家科学基金赞助，在网络环境下完成的模拟地震工程项目。
就是“钢纤维混凝土”-----外行翻译
以下是原文：
http://www.ns.umich.edu/htdocs/releases/story.php?id=7007
New building design withstands earthquake simulation
Click for video ANN ARBOR, Mich.—Researchers at the University of Michigan simulated an off-the-charts earthquake in a laboratory to test their new technique for bracing high-rise concrete buildings. Their technique passed the test, withstanding more movement than an earthquake would typically demand.
The engineers used steel fiber-reinforced concrete to develop a better kind of coupling beam that requires less reinforcement and is easier to construct. Coupling beams connect the walls of high rises around openings such as those for doorways, windows, and elevator shafts. These necessary openings can weaken walls.
"We simulated an earthquake that is beyond the range of the maximum credible earthquake and our test was very successful. Our fiber-reinforced concrete beams behaved as well as we expected they would, which is better than the beams in use today," said James Wight, the Frank E. Richart Jr. Collegiate Professor in the U-M Department of Civil and Environmental Engineering.
Click image for higher resolution Working with Wight on this project are Gustavo Parra-Montesinos, an associate professor in the Department of Civil and Environmental Engineering, and Remy Lequesne, a doctoral student in the same department.
Today, coupling beams are difficult to install and require intricate reinforcing bar skeletons. The U-M engineers created a simpler version made of a highly flowable, steel fiber-reinforced concrete.
"We took quite a bit of the cumbersome reinforcement out of the design and replaced it with steel fibers that can be added to the concrete while it's being mixed," Parra-Montesinos said. "Builders could use this fiber-reinforced concrete to build coupling beams that don't require as much reinforcement."
The engineers envision that their brand of beam would be cast off the construction site and then delivered. Nowadays, builders construct the beams, steel skeletons and all, bit by bit as they're building skyscrapers.
Their fiber-reinforced concrete has other benefits as well.
"The cracks that do occur are narrower because the fibers hold them together," Parra-Montesinos said.
The fibers are about one inch long and about the width of a needle.
The engineers performed their test in December on a 40-percent replica of a 4-story building wall that they built in the Structures Laboratory. They applied a peak load of 300,000 pounds against the building, pushing and pulling it with hydraulic actuators.
To quantify the results, they measured the building's drift, which is the motion at the top of the building compared with the motion at the base. In a large earthquake, a building might sustain a drift of 1 to 2 percent. The U-M structure easily withstood a drift of 3 percent.
The new beams could provide an easier, cheaper, stronger way to brace buildings in earthquake-prone areas.
The researchers are now working with a structural design firm to install the beams in several high rises soon to be under construction on the west coast.
This research is funded by the National Science Foundation under the Network for Earthquake Engineering Simulation Program.
Michigan Engineering:
The University of Michigan College of Engineering is ranked among the top engineering schools in the country. At more than $130 million annually, its engineering research budget is one of largest of any public university. Michigan Engineering is home to 11 academic departments and a National Science Foundation Engineering Research Center. The college plays a leading role in the Michigan Memorial Phoenix Energy Institute and hosts the world class Lurie Nanofabrication Facility. Michigan Engineering's premier scholarship, international scale and multidisciplinary scope combine to create The Michigan Difference. Find out more at http://www.engin.umich.edu/.
Related Links:
James Wight
Gustavo Parra-Montesinos
Contact: Nicole Casal Moore
Phone: (734) 647-1838
Engineers constructed a four-story, 40-percent replica of a building in a laboratory to test their new technique for bracing high rise buildings in earthquake zones. They simulated an earthquake by pushing and pulling the building with hydraulics. (Credit: Remy Lequesne)
The engineers used steel fiber-reinforced concrete to develop a better kind of coupling beam that requires less reinforcement and is easier to construct. Coupling beams connect the walls of high rises around openings such as those for doorways, windows, and elevator shafts. These necessary openings can weaken walls.
"We simulated an earthquake that is beyond the range of the maximum credible earthquake and our test was very successful. Our fiber-reinforced concrete beams behaved as well as we expected they would, which is better than the beams in use today," said James Wight, the Frank E. Richart Jr. Collegiate Professor in the U-M Department of Civil and Environmental Engineering.
Working with Wight on this project are Gustavo Parra-Montesinos, an associate professor in the Department of Civil and Environmental Engineering, and Remy Lequesne, a doctoral student in the same department.
Today, coupling beams are difficult to install and require intricate reinforcing bar skeletons. The U-M engineers created a simpler version made of a highly flowable, steel fiber-reinforced concrete.
"We took quite a bit of the cumbersome reinforcement out of the design and replaced it with steel fibers that can be added to the concrete while it's being mixed," Parra-Montesinos said. "Builders could use this fiber-reinforced concrete to build coupling beams that don't require as much reinforcement."
The engineers envision that their brand of beam would be cast off the construction site and then delivered. Nowadays, builders construct the beams, steel skeletons and all, bit by bit as they're building skyscrapers.
Their fiber-reinforced concrete has other benefits as well.
"The cracks that do occur are narrower because the fibers hold them together," Parra-Montesinos said.
The fibers are about one inch long and about the width of a needle.
The engineers performed their test in December on a 40-percent replica of a 4-story building wall that they built in the Structures Laboratory. They applied a peak load of 300,000 pounds against the building, pushing and pulling it with hydraulic actuators.
To quantify the results, they measured the building's drift, which is the motion at the top of the building compared with the motion at the base. In a large earthquake, a building might sustain a drift of 1 to 2 percent. The U-M structure easily withstood a drift of 3 percent.
The new beams could provide an easier, cheaper, stronger way to brace buildings in earthquake-prone areas.
The researchers are now working with a structural design firm to install the beams in several high rises soon to be under construction on the west coast.
This research is funded by the National Science Foundation under the Network for Earthquake Engineering Simulation Program.