One of the main issues involved during tunnel construction with tunnel boring machines is the tail gap grouting. This gap is between the external diameter of tunnel lining and the excavation boundary that is filled with high-pressure grouting materials. In this work, three different approaches of gap grouting modeling in the FLAC3D software are investigated with a special attention to the...

Grouted post-tensioned (PTd) concrete systems are widely used in long-span segmental bridges with a target service life of 100+ years. However, the usage inadequate grout materials and grouting practices have resulted formation unwanted air voids duct, which turn led to premature corrosion (say, within about 20 years) strands failure tendons. Also, re-grouting/repairing void regions localized a...

The feasibility and sensitivity of electrochemical noise (EN), electrochemical impedance spectroscopy (EIS), and linear polarization resistance (LPR) for detection of corrosion in post-tensioning (PT) components was investigated. The use of the electrical resistance (ER) technique, as well EIS and LPR, to detect air space corrosion at the grout voids was also explored. The results showed that h...

13 The use of externally bonded steel reinforced polymer (SRP) and steel reinforced grout (SRG) is a promising new technology for increasing fl a d b a 14 15 16 17 18 19 © 20

The use of externally bonded Steel-Reinforced Polymer (SRP) and Steel Reinforced Grout (SRG) composites is a promising new technology for increasing the flexural and shear capacities of reinforced concrete (RC) members. The reinforcement system in these composites is a sheet made up of unidirectional cords consisting of tightly wound ultra high strength steel wires. The reinforcement can be mol...

Pull-out experiments were performed on four carbon fiber-reinforced polymer (CFRP) ground anchors simulating their applications in rock and soil. The CFRP tendons used in these anchors comprise a single-strap end on both the ground and air sides. On the ground side, the single-strap end is embedded in a cylinder of high-strength grout which fits into the borehole. In rock applications, the grou...

Grout is a cement-based material with high strength and workability that allowing it to be injected into small cracks or leaky areas. It usually used patch concrete holes, but may also fill voids under metal bases digging anchors. Furthermore, grout efficiently in the production process of semi-flexible pavement mixtures. The purpose this study characterize effect ingredients on their mechanica...

In the present research, optimum condition of grout consisting cement, fly ash, superplasticizer, and water was determined to produce most durable impermeable deep mixing columns (DMC) on silty soils. It is aimed reduce cost environmental pollution by using high-rate ash in grout. Superplasticizer additive used increase flow consistency ash. The design experiments made 5-parameter 4-level L16 o...