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，其温室气体排放量更少，强度更高。用新型水泥制造的普通强度砌块的相关温室气体比强度更高的砌块低得多。新型水泥将通过使用辅助胶凝材料来生产，其中包括反应性偏高岭土和晶种材料，以促进水合硅酸钙（铝）的产生，水合硅酸钙是水泥浆中具有特定性能的主要粘结相。认识到纳米水泥可产生非常高的强度，将新型水泥研磨至更小的平均尺寸将产生高强度混凝土。该研究有两个主要目标。首先是确定可以替代当前生产的新型水泥的混凝土混合物，从而减少与“标准”混凝土砌块砌体相关的温室气体排放。二是利用新型水泥生产高强度砌块，用混凝土砌块建造更大、更强的结构，从而扩大砌体的使用范围，降低建筑成本。这可能需要配制与高强度砌块相容的砂浆以实现高强度砌体。此外，充分利用新砌块可能会受到加拿大砖石标准中当前对高墙设计的限制的限制。最近的工作表明，与测试结果或世界各地的其他标准相比，按照当前标准中的程序设计高墙的方式非常保守，而且不太准确。因此，有必要检查现行标准中使用的方法，并确定如何更新它们，以便它们能够更有效地使用砌体，但特别是，它们鼓励在建造高墙时充分有效地使用高强度砌块。该提案得到了加拿大混凝土砖石生产商协会的支持，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该申请，并将通过为其承包商成员增加工作而受益。

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.