This article develops an enhanced UHPC-grout shear connection for steel-concrete composite bridges with precast decks. The primary improvement is the use of ultra-high performance concrete (UHPC) as grout. To validate constructability and mechanical new connection, two series experimental tests (including grouting push-out tests) were conducted. Results from show that both pressure method self-...

considering the seepage and choosing an efficient sealing method is very important in dam projects. this issue has a close relationship with engineering geological properties of the dam site. chapar-abad dam is an inhomogeneous earth-fill dam of 44.5 meters height, crest length about 427 meters and a reservoir capacity of 127 million cubic meters. the dam project is under construction and is lo...

In this preliminary study, the complexity of the corrosion phenomenon of post-tensioning strands in grouted anchorage assemblies was examined and both physicochemical and electrochemical key technical issues were identified. Measurements of oxygen reduction efficiency in high pH electrolytes were conducted to obtain polarization parameters to be used in modeling. The time evolution of electrica...

This paper presents a modified form of the Walker-Anderson (W-A) model for analyzing high velocity penetration of an eroding projectile into a concrete target in which the W-A model is improved by incorporating calculations for the plastic flow field of concrete in terms of its compressibility and strain rate sensitivity under severe pressure. With the changes to and calculations of plastic fie...

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...

objective: contradictory results have been reported over microleakage studies of restorative materials and methods. despite the number of publications on leakage there are few evidences comparing the different microleakage evaluation methods. the purpose of the present study was to compare the clearing technique and longitudinal sectioning in the evaluation of dye penetration along a glass fibe...

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