Victor C. Li | |
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Known for | Engineered cementitious composite |
Academic background | |
Education | Brown University (B.Sc., M.Sc., Ph.D.) |
Academic work | |
Institutions | University of Michigan |
Victor C. Li is the James R. Rice Distinguished University Professor of Engineering and the E.B. Wylie Collegiate Professor of Civil Engineering at the University of Michigan. He is also Director of the Center for Low Carbon Built Environment at the University of Michigan College of Engineering. [1] [2] Li led the team that developed engineered cementitious composites (EEC),popularly known as "bendable concrete." [3] [4] Li argues EEC can increase the durability of infrastructure and reduce its carbon footprint. [5]
Li grew up in Hong Kong;he moved to the U.S. in 1973 to attend Brown University in Providence,Rhode Island. He graduated with an undergraduate degree in economics and engineering from Brown in 1977. Li remained at the Brown University School of Engineering for graduate studies,earning an M.Sc. in mechanical engineering in 1978 and a Ph.D. in solid and structural mechanics in 1981. [6] At Brown,Li was mentored by James R. Rice and Lambert Ben Freund. [7]
Li taught at the Massachusetts Institute of Technology from 1981 to 1989 as an assistant and later associate professor. He joined the University of Michigan in 1990 as an associate professor,becoming a full professor in 1993. [8] Between 1999 and 2004,Li was the Højgaard Visiting Professor of Concrete Technology at the Technical University of Denmark in Kongens Lyngby,Denmark.
In 2005,Li and his team of researchers gained attention for developing a new type of fiber-reinforced bendable concrete. [9] [10] In 2019,Li published Engineered Cementitious Composites (ECC):Bendable Concrete for Sustainable and Resilient Infrastructure,the first book devoted to the subject of ECCs.
In 2004,Li was awarded a doctorate honoris causa from the Technical University of Denmark.
Concrete is a composite material composed of aggregate bonded together with a fluid cement that cures over time. Concrete is the second-most-used substance in the world after water,and is the most widely used building material. Its usage worldwide,ton for ton,is twice that of steel,wood,plastics,and aluminium combined..
A composite material is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure,the individual elements remain separate and distinct,distinguishing composites from mixtures and solid solutions.
Engineered wood,also called mass timber,composite wood,man-made wood,or manufactured board,includes a range of derivative wood products which are manufactured by binding or fixing the strands,particles,fibres,or veneers or boards of wood,together with adhesives,or other methods of fixation to form composite material. The panels vary in size but can range upwards of 64 by 8 feet and in the case of cross-laminated timber (CLT) can be of any thickness from a few inches to 16 inches (410 mm) or more. These products are engineered to precise design specifications,which are tested to meet national or international standards and provide uniformity and predictability in their structural performance. Engineered wood products are used in a variety of applications,from home construction to commercial buildings to industrial products. The products can be used for joists and beams that replace steel in many building projects. The term mass timber describes a group of building materials that can replace concrete assemblies.
Lynn Ann Conway is an American computer scientist,electrical engineer and transgender activist.
Syntactic foams are composite materials synthesized by filling a metal,polymer,or ceramic matrix with hollow spheres called microballoons or cenospheres or non-hollow spheres. In this context,"syntactic" means "put together." The presence of hollow particles results in lower density,higher specific strength,lower coefficient of thermal expansion,and,in some cases,radar or sonar transparency. A manufacturing method for low density syntactic foams is based on the principle of buoyancy.
Silica fume,also known as microsilica,is an amorphous (non-crystalline) polymorph of silicon dioxide,silica. It is an ultrafine powder collected as a by-product of the silicon and ferrosilicon alloy production and consists of spherical particles with an average particle diameter of 150 nm. The main field of application is as pozzolanic material for high performance concrete.
Engineered Cementitious Composite (ECC),also called Strain Hardening Cement-based Composites (SHCC) or more popularly as bendable concrete,is an easily molded mortar-based composite reinforced with specially selected short random fibers,usually polymer fibers. Unlike regular concrete,ECC has a tensile strain capacity in the range of 3–7%,compared to 0.01% for ordinary portland cement (OPC) paste,mortar or concrete. ECC therefore acts more like a ductile metal material rather than a brittle glass material,leading to a wide variety of applications.
Metakaolin is the anhydrous calcined form of the clay mineral kaolinite. Minerals that are rich in kaolinite are known as china clay or kaolin,traditionally used in the manufacture of porcelain. The particle size of metakaolin is smaller than cement particles,but not as fine as silica fume.
Fiber-reinforced concrete or fibre-reinforced concrete (FRC) is concrete containing fibrous material which increases its structural integrity. It contains short discrete fibers that are uniformly distributed and randomly oriented. Fibers include steel fibers,glass fibers,synthetic fibers and natural fibers –each of which lend varying properties to the concrete. In addition,the character of fiber-reinforced concrete changes with varying concretes,fiber materials,geometries,distribution,orientation,and densities.
High-performance fiber-reinforced cementitious composites (HPFRCCs) are a group of fiber-reinforced cement-based composites that possess the unique ability to flex and self-strengthen before fracturing. This particular class of concrete was developed with the goal of solving the structural problems inherent with today’s typical concrete,such as its tendency to fail in a brittle manner under excessive loading and its lack of long-term durability. Because of their design and composition,HPFRCCs possess the remarkable ability to plastically yield and harden under excessive loading,so that they flex or deform before fracturing,a behavior similar to that exhibited by most metals under tensile or bending stresses. Because of this capability,HPFRCCs are more resistant to cracking and last considerably longer than normal concrete. Another extremely desirable property of HPFRCCs is their low density. A less dense,and hence lighter material means that HPFRCCs could eventually require much less energy to produce and handle,deeming them a more economical building material. Because of HPFRCCs’lightweight composition and ability to strain harden,it has been proposed that they could eventually become a more durable and efficient alternative to typical concrete.
Deborah Duen Ling Chung is an American scientist and university professor.
Concrete is produced in a variety of compositions,finishes and performance characteristics to meet a wide range of needs.
Energetically modified cements (EMCs) are a class of cements made from pozzolans,silica sand,blast furnace slag,or Portland cement. The term "energetically modified" arises by virtue of the mechanochemistry process applied to the raw material,more accurately classified as "high energy ball milling" (HEBM). This causes,amongst others,a thermodynamic transformation in the material to increase its chemical reactivity. For EMCs,the HEBM process used is a unique form of specialised vibratory milling discovered in Sweden and applied only to cementitious materials,here called "EMC Activation".
Nanocem is a consortium of academic and private industry groups that researches the properties of cement and concrete on the nano- and micro-scales,with a particular focus on reducing carbon dioxide emissions at all stages of production. Nanocem was founded as an independent consortium in 2004 after a rejection of a 2002 bid to the Network of Excellence. The research is conducted at a fundamental level. Yet high levels of industry involvement allow to focus on solutions that can work in practice and not just in theory.
Nemkumar Banthia FRSC,is an Indian-born Canadian engineer and professor of civil engineering at the University of British Columbia and the CEO of IC-IMPACTS. He is best known for his research in the fields of cement-based and polymer-based fiber reinforced composites,particularly on testing and standardization,fracture behavior,strain-rate effects,durability and development of sustainable materials.
Abir Al-Tabbaa CEng FICE is a Professor of Geotechnical Engineering at the University of Cambridge. She works on intelligent materials for infrastructure. She is the Director of the Future Infrastructure and Built Environment Doctoral Training Centre.
Reginald DesRoches is an American civil engineer who,as of July 1,2022,serves as the president at Rice University. From 2020 until 2022,he served as provost of Rice. Earlier,beginning in 2017,he was the dean of engineering at Rice's school of engineering,and from 2012 to 2017,DesRoches held the Karen and John Huff Chair at the Georgia Institute of Technology.
A living building material (LBM) is a material used in construction or industrial design that behaves in a way resembling a living organism. Examples include:self-mending biocement,self-replicating concrete replacement,and mycelium-based composites for construction and packaging. Artistic projects include building components and household items.
Ellen Marie Arruda is an American mechanical engineer known for her research on the mechanical properties of polymers and on tissue engineering,with applications including the design of improved football helmets,artificial tooth enamel that can withstand high-shock and high-vibration environments,and nanolayered composite materials that are lightweight,as strong as steel,and transparent. The Arruda–Boyce model for the behavior of rubber-like polymers is named for her and her doctoral advisor Mary Cunningham Boyce,with whom she published it in 1993. She is Maria Comninou Collegiate Professor of Mechanical Engineering and Tim Manganello / Borg Warner Department Chair of Mechanical Engineering at the University of Michigan.
Self-healing concrete is characterized as the capability of concrete to fix its cracks on its own autogenously or autonomously. It not only seals the cracks but also partially or entirely recovers the mechanical properties of the structural elements. This kind of concrete is also known as self-repairing concrete. Because concrete has a poor tensile strength compared to other building materials,it often develops cracks in the surface. These cracks reduce the durability of the concrete because they facilitate the flow of liquids and gases that may contain harmful compounds. If microcracks expand and reach the reinforcement,not only will the concrete itself be susceptible to attack,but so will the reinforcement steel bars. Therefore,it is essential to limit the crack's width and repair it as quickly as feasible. Self-healing concrete would not only make the material more sustainable,but it would also contribute to an increase in the service life of concrete structures and make the material more durable and environmentally friendly.