Improving the performance of ground-supported slabs subjected to extreme environmental conditions using rigid high strength fiberglass geogrids

一个日益受到关注的问题是直接放置在地面上并经受恶劣室外环境条件的结构元件的快速劣化。例如，人行道通常由通常暴露于极端天气和腐蚀性条件（例如，冬季的除冰盐）的混凝土板制成。加拿大约有10万公里的人行道，其中约20%需要更换，估计费用超过10亿美元。市政财政资源有限，没有足够的资金来应付日益恶化的基础设施。标准做法是建造大多数混凝土人行道，使用非钢筋或名义上的钢筋来控制裂缝宽度。然而，存在于除冰盐、海水、海洋空气等中的含有氯化物的化学物质，可以攻击将混凝土结合在一起的粘合剂，并导致钢筋腐蚀。过去曾尝试使用传统的聚合物土工格栅作为混凝土加固材料，然而，聚合物土工格栅的延展性导致过度变形和整体性能差。泰坦环境控制有限公司正在与麦吉尔大学合作，研究使用高强度玻璃纤维（ConForce）土工格栅材料加固地面支撑混凝土结构的效率。在联盟赠款的支持下，该项目将为其他土工格栅加固应用铺平道路，并促进更多的大学合作。在麦吉尔大学进行的初步指数测试表明，在失败的诱导应变约为1%，这是聚合物土工格栅的约七分之一。此外，泰坦在阿尔伯塔的新人行道上进行的试点实地测试结果显示出可喜的成果。预计本研究的结果将有助于工程师设计更可持续的地面支撑结构。这项研究对加拿大非常重要，因为所提出的施工方法可以显著提高这些结构的使用寿命。这项研究资助将有助于培养一名博士生、一名硕士生和两名本科生。

A problem of growing concern is the fast deterioration of structural elements placed directly on the ground and subjected to harsh outdoor environmental conditions. For example, sidewalks are typically made out of concrete slabs that are usually exposed to extreme weather and corrosive conditions (e.g. de-icing salts in winter). There are about 100,000 km of sidewalks in Canada with about 20 percent in need of replacement in a given year at an estimated cost of more than $1 billion. Municipal financial resources are limited and there are insufficient funds to keep pace with the deteriorating infrastructure. The standard practice is to build most concrete sidewalks using unreinforced or nominally steel-reinforced for crack-width control. However, the presence of chemicals containing chlorides, found in de-icing salt, ocean water, marine air, etc., can attack the bonds that hold concrete together and contribute to steel corrosion. Attempts have been made in the past to use conventional polymeric geogrid as concrete reinforcement material, however, the ductile nature of polymeric geogrid resulted in excessive deformation and overall poor performance.Titan Environmental Containment Ltd. is teaming up with McGill University to investigate the efficiency of using high strength fiberglass (ConForce) geogrid material to reinforce ground-supported concrete structures. Supported by Alliance grant, this project will pave the way for other geogrid-reinforced applications and promote more university collaboration. Preliminary index tests performed at McGill University indicated that the induced strain at failure is about 1%, which is about one-seventh of that of polymeric geogrid. In addition, the results of pilot field tests done by Titan on new sidewalks in Alberta showed promising results. It is expected that the results of this study will help engineers in designing more sustainable ground supported structures. This study is of importance to Canada as the proposed construction approach could significantly enhance the service life of these structures.This research grant will contribute to the training of one PhD, one MSc, and two undergraduate students.