由於社會文明的進步,世界各地的建築物大都採用鋼筋混凝土的結構,然而混凝土結構物會因內部及外在因素之影響,造成混凝土結構產生裂縫或損壞,對建築物的安全性影響甚鉅。目前國內工程對於各種型態及寬度的結構裂縫,其修補材料選用並無明確規範可依循。傳統裂縫修補材料大部分使用環氧樹脂,但環氧樹脂其耐久及耐高溫之性能較差,於50℃環境中,便會產生熱變形導致黏著界面產生部份脫落,故遭火害後其修補效果會下降。 無機聚合樹脂主要由富含矽、鋁之原料、鹼金屬溶液與鹼金屬矽酸鹽溶液混合製成,其原料來源廣泛且製作流程簡易,並具有高早期強度、耐酸鹼腐蝕、耐久性佳及耐火性質良好等特性。本研究以變高嶺石為固體原料,並添加玻璃粉及玻璃纖維,與矽酸鈉溶液及NaOH溶液混合配製成不同SiO2/Na2O莫耳比之鹼性溶液,將其製成無機聚合樹脂,作為混凝土裂縫修補之膠結劑。 研究結果顯示,SiO2/Na2O莫耳比為0.75之鹼性溶液所製成之無機聚合樹脂 具有較佳之機械強度及物理性質,其試體修補效果較佳。添加玻璃粉及玻璃纖維後之無機聚合樹脂,因其機械強度大、硬化時間短及乾縮性小等特性,且樹脂中矽酸鈉含量增加,因而黏結性增加,修補效果能更進一步提升。無機聚合樹脂修補試體於火害環境下,其修補效果雖會變差,但於500℃仍能保持相當程度之裂縫修補能力。
By the progress of civilization development, most architectures in the world are made of reinforced concrete. However, concrete structures probably cause cracks by plenty of endogenetic or extrinsic factors, such as massive earthquakes or unpredictable weather. This research utilized metakaolinite, glass powder, glass fiber and alkali solution with different SiO2/Na2O molar ratio to form geopolymer resin as the binder for repairing concrete fracture. According to the experimental results, the geopolymer resin with SiO2/Na2O molar ratio of 0.75 has better mechanical/physical properties, and the efficiency restoring maintenance characteristics. With additional glass powder and/or glass fiber, the performance of geopolymer resin can be improved, because of the greater mechanical intensity, shorter time of hardness, and diminutive dry shrinkage. The geopolymer resin is also a fire resistance material. The mortar of repairing crack still works even under firing environment. Therefore, using geopolymer resin as the binder for repairing crack of concrete has great potential for engineering and construction applications.