• Title/Summary/Keyword: skin mobilization

Search Result 22, Processing Time 0.017 seconds

The responses of battered pile to tunnelling at different depths relative to the pile length

  • Mukhtiar Ali Soomro;Naeem Mangi;Dildar Ali Mangnejo;Zongyu Zhang
    • Geomechanics and Engineering
    • /
    • v.35 no.6
    • /
    • pp.603-615
    • /
    • 2023
  • Population growth and urbanization prompted engineers to propose more sophisticated and efficient transportation methods, such as underground transit systems. However, due to limited urban space, it is necessary to construct these tunnels in close proximity to existing infrastructure like high-rise buildings and bridges. Battered piles have been widely used for their higher stiffness and bearing capacity compared to vertical piles, making them effective in resisting lateral loads from winds, soil pressures, and impacts. Considerable prior research has been concerned with understanding the vertical pile response to tunnel excavation. However, the three-dimensional effects of tunnelling on adjacent battered piled foundations are still not investigated. This study investigates the response of a single battered pile to tunnelling at three critical depths along the pile: near the pile shaft (S), next to the pile (T), and below the pile toe (B). An advanced hypoplastic model capable of capturing small strain stiffness is used to simulate clay behaviour. The computed results reveal that settlement and load transfer mechanisms along the battered pile, resulting from tunnelling, depend significantly on the tunnel's location relative the length of the pile. The largest settlement of the battered pile occurs in the case of T. Conversely, the greatest pile head deflection is caused by tunnelling near the pile shaft. The battered pile experiences "dragload" due to negative skin friction mobilization resulting from tunnel excavation in the case of S. The battered pile is susceptible to induced bending moments when tunnelling occurs near the pile shaft S whereas the magnitude of induced bending moment is minimal in the case of B.

Gracilis Muscle Transplantation in Neglected Brachial Plexus Palsy (진구성 상완 신경총 마비에 대한 유리박근이식술)

  • Chung, Duke-Whan;Han, Chung-Soo;Ok, Jae-Chul;Cho, Chang-Hyun
    • Archives of Reconstructive Microsurgery
    • /
    • v.6 no.1
    • /
    • pp.73-79
    • /
    • 1997
  • Complete denervation after severe brachial plexus injury make significant muscle atrophy with loss of proper function. It is much helpful to reconstruct the essential function of the elbow flexion movement in patient with total loss of elbow flexion motion after brachial plexus lesion which was not recovered with nerve surgery or long term conservative treatment from onset. In whole arm type brachial plexus injury, if there were no response to neurotization or neglected from injury, the volume of the denervated muscle is significantely reduced month by month. About 18 months most of the muscle fibers change to fibrous tissues and markedly atrophied irreversibly, further waiting is no more meaningful from that period. Authors performed 14 cases of functioning gracilis muscle transfer from 1981 to 1995 with microneurovascular technique, neuromusculocutaneous free flaps were performed for reconstruction of lost elbow flexion function. Average follow-up period was 5 years and 6 months. We used couple of intercostal nerves as a recipient nerve which were anastomosed to muscular nerve from obturator nerve in all cases. Recipient vessels were three deep brachial artery and eleven brachial artery which were anastomosed to medial femoral circumflex artery with end to end or end to side fashion. Average resting length of the transplanted gracilis were 24 cm. We can get average 54 degree flexion range of elbow with fair muscle power from flail elbow. There were one case of muscle necrosis with lately developed thrombosis of microvascular anastomosed site which comes from insufficient recipient arterial condition, 3 cases of partial marginal necrosis of distal skin of the transplanted part which were not significant problem with spontaneously solved with time goes by gracilis muscle has constant neurovascular pattern with relatively easy harvesting donor with minimal donor morbidity. Especially it has similar length and shape with biceps brachii muscle of upper arm and longer nerve pedicle which can neurorrhaphy with intercostal nerve without nerve graft if sufficient mobilization of the nerves from both sides of gracilis and intercostal region. Authors can propose gracilis muscle transplantation with intercostal nerves neurotization is helpful method with minimal donor morbidity for neglected brachial plexus palsy patients.

  • PDF