489 research outputs found
Settlement of a Light Rail Pier Supported on Large Diameter Bored Piles Remediated by Jet Grouting
A support Pier (Pier 161) for a Light Rail line being constructed for the Metro Manila Light Rail Project encountered large settlements after the installation of the Precast Deck Girders. This pier supports bridge crossing across the San Juan River with a total span of sixty (60) meters. This Pier is supported on six (6) 1500 mm diameter bored piles designed to extend down to 17 meters or socketed into bedrock at least 2.0 meters based on design requirements. The structure started to settle during the erection of the superstructure when the dead load reached about 700 metric tons. Total settlement was about 42 mm when the erection was halted at a dead load of about 1600 metric tons. The pier was designed to carry a maximum total load of about 2100 metric tons (DL + LL). Subsequent subsurface investigation conducted by our office indicated that the bored piles were terminated prematurely and were not socketed into bedrock as originally specified. The Bored pile tips were resting on approximately 150 mm of soft to very soft clay and highly weathered bedrock, which is partly natural soil and drill cuttings. Several remediation procedures were considered but finally, Jet grouting was selected . This paper discusses the problems associated with the settlement and the ensuing solution using Jet Grouted Piles
Magnetic Phase Transition and Magnetization Plateau in CsCuBr
The crystal structure of CsCuBr is the same as that of
CsCuCl, which has been characterized as a spin-1/2
quasi-two-dimensional frustrated system. The magnetic properties of
CsCuBr were investigated by magnetization and specific heat
measurements. The phase transition at zero magnetic field was detected at
K. It was observed that the magnetization curve has a plateau
at about one-third of the saturation magnetization for magnetic field
parallel to the - and -axes, while no plateau was observed for
. The field-induced phase transition to the plateau state appears
to be of the first order. The mechanism leading to the magnetization plateau is
discussed.Comment: 6 pages, 4 figures, 4 eps files, ptptex, will appear in Supplement of
Progress in Theoretical Physic
Ferromagnetism induced in anisotropic stacked kagome-lattice antiferromagnet CsCuCeF
The magnetic properties of CsCuCeF were investigated through
magnetization and specific heat measurements. CsCuCeF is
composed of a buckled kagome lattice of Cu, which is stacked along the b
axis. The exchange network in the buckled kagome lattice is strongly
anisotropic. Consequently, CsCuCeF can be divided into two
subsystems: alternating Heisenberg chains with strong antiferromagnetic
exchange interactions and dangling spins. The dangling spins couple with one
another via effective exchange interactions, which are mediated by chain spins.
The dangling spins are further divided into two subsystems, DS1 and DS2. The
dangling spins in DS1 undergo three-dimensional ferromagnetic ordering at 3.14
K, while those in DS2 remain paramagnetic down to 0.35 K. The effective
interaction between the DS1 spins is approximately expressed by the
ferromagnetic model with the direction parallel to the
crystallographic c axis. A magnetic phase diagram for was
obtained and was analyzed within the framework of the molecular field
approximation. With increasing magnetic field, the dangling spins are polarized
and the magnetization curve exhibits a wide plateau at one-third of the
saturation magnetization.Comment: 10 pages, 12 figure
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