The Application of Novel Cements in Concrete Block Manufacturing Towards Low Carbon-High Strength Masonry

我们建议开发用于混凝土砌块生产的新型水泥，同时伴随的温室气体排放要少得多，而且强度更高。用新型水泥生产的普通强度砌块的相关温室气体将比强度更高的砌块低得多。这种新型水泥将通过使用包括活性偏高岭土和种子材料的辅助胶凝材料来生产，以促进具有特定性能的水泥浆体中的主要结合相--水化硅酸钙的产生。认识到纳米水泥能产生非常高的强度，将新型水泥研磨成小得多的平均尺寸将产生高强度混凝土。这项研究主要有两个目的。第一个是确定混凝土与新型水泥的混合物，这些水泥可以取代目前的生产，从而减少与“标准”混凝土砌块砌块相关的温室气体排放。第二是使用新型水泥生产高强度砌块，可以用混凝土砌块建造更大更坚固的结构，从而扩大砖石的使用，降低建筑成本。这可能需要配制与高强度砌块兼容的砂浆，以实现高强度砌块。此外，充分利用新砌块可能会受到加拿大砖石标准中目前对高层墙设计的限制。最近的工作表明，按照现行标准的程序设计高墙的方法非常保守，与世界各地的测试结果或其他标准相比也不是很准确。因此，有必要检查当前标准中使用的方法，并确定如何更新这些方法，以便总体上能够更有效地使用砖石，但特别是，它们鼓励在建造高层墙时充分和有效地使用高强度砌块。这项提议得到了加拿大混凝土砌块生产商协会的支持，该协会的成员将受益于销售更环保和更坚固的混凝土砌块的能力。加拿大砖石设计中心也支持这项申请，并将通过增加承包商成员的工作量而受益。

We propose to develop new cements for concrete block production with much less associated Greenhouse gas emission and with higher strength. Normal strength blocks manufactured with the novel cements will have much lower associated GHG than the stronger blocks. The novel cements will be produced by using supplementary cementitious materials which include reactive metakaolin and a seeding material to encourage the production of calcium-(alumino-)silicate-hydrate, the primary binding phase in cement paste, with specific properties. Recognizing that nano-cements produce very high strength, grinding the novel cements to a much smaller average size will produce high strength concretes. There are two main objectives of the research. The first is to determine concrete mixes with novel cements that can replace current production and thereby reduce the greenhouse gas emissions associated with "standard" concrete block masonry. The second is to use novel cements to produce high strength blocks that can be used to build bigger and stronger structures from concrete blockwork and thereby expand the use of masonry, and reduce construction costs. This may require the formulation of a mortar compatible with the high strength block to achieve high strength masonry. In addition, taking full advantage of the new blocks could be limited by the current restrictions on tall wall design in the Canadian masonry standard. Recent work has shown that the way tall walls are designed following the procedure in the current standard is very conservative and not very accurate compared to test results or other standards around the world. Therefore there is a need to examine the methods used in the current standard and determine how to update them so they allow more effective use of masonry in general, but in particular, they encourage full and effective use of the high strength blocks in the construction of tall walls. The proposal is supported by the Canadian Concrete Masonry Producers Association whose members will benefit from the ability to market both "greener" and stronger concrete blocks. The Canada Masonry Design Centre also supports the application and will benefit through increased work for its contractor members.