A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Development of self-stressing Engineered Cementitious Composites (ECC)
https://orcid.org/0000-0003-1503-6076
https://orcid.org/0000-0002-8678-3493
Abstract While high ductility Engineered Cementitious Composites (ECC) have demonstrated effectiveness for infrastructure repair, the microcracking induced by the high material shrinkage may decrease the structural durability of ECC in aggressive environments. The objective of this research is to develop a self-stressing ECC, the expansion of which against the restraint of the repaired structure automatically induces pressure onto the repair material. Super absorbent polymer (SAP), shrinkage reducing agent (SRA), and calcium sulphoaluminate cement/expansive additive (CSA) were utilized together with Portland cement to tailor the composite expansion and expansive pressure. Free drying expansion/shrinkage, restrained expansive stress, and tensile performance were examined through standard shrinkage measurement, steel ring restrain test, and uniaxial tensile test, respectively. It was found that the 28 days drying shrinkage was decreased by 47% due to the use of SRA but was slightly increased when SAP was used. Substituting 42% of OPC with CSA (K42) increased ECC strength and ductility. The K42-ECC experienced a maximum expansion of 3756 με at 3 days and retained 2026 με expansion at 28 days. However, the expansion loss between 3 days and 28 days counteracted the expansive pressure. The deliberate combination of SRA and CSA provides a self-stressing effect tailoring the maximum expansion and expansion loss. The self-stressing performance along with a 7% ultra-high strain capacity and average crack width of 35–44 μm at 3% strain promotes the developed ECC as a more durable material for infrastructure repair.
Highlights A self-stressing PP-ECC was developed using SRA and CSA. Ultra-high tensile strain capacity (7%) with crack width below 45 μm for PP-ECC. CSA increased while SRA decreased the strength, but both enhanced the ductility. Peak expansion occurred at 3.3 d and followed by a reduced expansion. The residual expansion under restraint induces self-pressure on the repair material.
Development of self-stressing Engineered Cementitious Composites (ECC)
https://orcid.org/0000-0003-1503-6076
https://orcid.org/0000-0002-8678-3493
Abstract While high ductility Engineered Cementitious Composites (ECC) have demonstrated effectiveness for infrastructure repair, the microcracking induced by the high material shrinkage may decrease the structural durability of ECC in aggressive environments. The objective of this research is to develop a self-stressing ECC, the expansion of which against the restraint of the repaired structure automatically induces pressure onto the repair material. Super absorbent polymer (SAP), shrinkage reducing agent (SRA), and calcium sulphoaluminate cement/expansive additive (CSA) were utilized together with Portland cement to tailor the composite expansion and expansive pressure. Free drying expansion/shrinkage, restrained expansive stress, and tensile performance were examined through standard shrinkage measurement, steel ring restrain test, and uniaxial tensile test, respectively. It was found that the 28 days drying shrinkage was decreased by 47% due to the use of SRA but was slightly increased when SAP was used. Substituting 42% of OPC with CSA (K42) increased ECC strength and ductility. The K42-ECC experienced a maximum expansion of 3756 με at 3 days and retained 2026 με expansion at 28 days. However, the expansion loss between 3 days and 28 days counteracted the expansive pressure. The deliberate combination of SRA and CSA provides a self-stressing effect tailoring the maximum expansion and expansion loss. The self-stressing performance along with a 7% ultra-high strain capacity and average crack width of 35–44 μm at 3% strain promotes the developed ECC as a more durable material for infrastructure repair.
Highlights A self-stressing PP-ECC was developed using SRA and CSA. Ultra-high tensile strain capacity (7%) with crack width below 45 μm for PP-ECC. CSA increased while SRA decreased the strength, but both enhanced the ductility. Peak expansion occurred at 3.3 d and followed by a reduced expansion. The residual expansion under restraint induces self-pressure on the repair material.
Development of self-stressing Engineered Cementitious Composites (ECC)
https://orcid.org/0000-0003-1503-6076
https://orcid.org/0000-0002-8678-3493
Abstract While high ductility Engineered Cementitious Composites (ECC) have demonstrated effectiveness for infrastructure repair, the microcracking induced by the high material shrinkage may decrease the structural durability of ECC in aggressive environments. The objective of this research is to develop a self-stressing ECC, the expansion of which against the restraint of the repaired structure automatically induces pressure onto the repair material. Super absorbent polymer (SAP), shrinkage reducing agent (SRA), and calcium sulphoaluminate cement/expansive additive (CSA) were utilized together with Portland cement to tailor the composite expansion and expansive pressure. Free drying expansion/shrinkage, restrained expansive stress, and tensile performance were examined through standard shrinkage measurement, steel ring restrain test, and uniaxial tensile test, respectively. It was found that the 28 days drying shrinkage was decreased by 47% due to the use of SRA but was slightly increased when SAP was used. Substituting 42% of OPC with CSA (K42) increased ECC strength and ductility. The K42-ECC experienced a maximum expansion of 3756 με at 3 days and retained 2026 με expansion at 28 days. However, the expansion loss between 3 days and 28 days counteracted the expansive pressure. The deliberate combination of SRA and CSA provides a self-stressing effect tailoring the maximum expansion and expansion loss. The self-stressing performance along with a 7% ultra-high strain capacity and average crack width of 35–44 μm at 3% strain promotes the developed ECC as a more durable material for infrastructure repair.
Highlights A self-stressing PP-ECC was developed using SRA and CSA. Ultra-high tensile strain capacity (7%) with crack width below 45 μm for PP-ECC. CSA increased while SRA decreased the strength, but both enhanced the ductility. Peak expansion occurred at 3.3 d and followed by a reduced expansion. The residual expansion under restraint induces self-pressure on the repair material.
Development of self-stressing Engineered Cementitious Composites (ECC)
Zhu, He (author) / Zhang, Duo (author) / Wang, Yichao (author) / Wang, Tianyu (author) / Li, Victor C. (author)
2021-01-04
Article (Journal)
Electronic Resource
English
| European Patent Office | 2021
| European Patent Office | 2018
Self-cleaning engineered cementitious composites
| Elsevier | 2015