During earth pressure balance (EPB) shield tunnelling in sandy ground, not only foam but also other conditioning agents need to be injected reduce the permeability of muck and avoid water spewing out screw conveyor. Permeability tests were carried study characteristics conditioned sand under high hydraulic gradients. A low bentonite slurry injection ratio (BIR) enhanced workability foam-conditi...

earth pressure balance tunnel boring machines (epb-tbms) are favorably applied in urban tunneling projects. despite their numerous advantages, considerable delays and high maintenance cost are the main disadvantages these machines suffer from. reliability, availability, and maintainability (ram) analysis is a practical technique that uses failure and repair dataset obtained over a reasonable ti...

Due to urbanization and population increase, need for metro tunnels, has been considerably increased in urban areas. Estimating the surface settlement caused by tunnel excavation is an important task especially where the tunnels are excavated in urban areas or beneath important structures. Many models have been established for this purpose by extracting the relationship between the settlement a...

Foam as a soil conditioner can transform the mechanical properties of excavated natural muck and lubricate interface between cutting tools muck, thus reducing tools’ wear promoting efficiency earth pressure balance (EPB) shield tunneling. This paper aims to explore meso-mechanism foam in improving workability sand by combining discrete element modeling (DEM) with experimental investigations slu...

Deformation of ground during tunnelling projects is one the complex issues that required to be monitored carefully avoid unexpected damages and human losses. Accurate prediction settlement (GS) a crucial concern for problems, adequate predictive model can vital tool tunnel designers simulate accurately. This study proposes relatively new hybrid artificial intelligence (AI) models predict earth ...

BACKGROUND de Quervain's disease is a condition in which there is pain in the radial styloid process caused by stenosing tenosynovitis of the abductor pollicis longus (APL) or/and extensor pollicis brevis (EPB) tendons in the first extensor compartment of the wrist. In this study we studied variations in the tendons of the EPB in the first extensor compartment and its site of insertion. METHO...

Using the Raji cell line as the immunogen source, we established stable murine hybridomas that secrete B-lymphocyte-specific monoclonal antibodies (MAbs). Two clones, designated EPB-1 and EPB-2, were selected for further study. Both EPB-1 and EPB-2 were typed by reaction with subclass-specific rabbit anti-mouse antibodies and were found to be IgG1 and IgG2a, with kappa-light chains, respectivel...

RESULTS: Nine of the 10 arms were male. The APL tendon had a mean of 3.3 ± 1.3 slips. The EPB tendon had one slip in all specimens. Seven compartments (70%) had an identifiable EPB subcompartment and four (57%) were thick. An osseous ridge was seen in 2 specimens, both with a thick subcompartment. The two arms with osseous ridges revealed radiopaque ridges on x-ray. Radiologists’ x-ray reviews ...

The visualization system of soil fluidity in the chamber EPB (Earth Pressure Balanced) shield has been developed to maintain appropriate excavated real time during advance under tunnel construction. For further improvement system, agitation tests fluid admixed with foam have carried out study relationship between number rotations and agitating torque soil. It is confirmed by that sand reduces i...