10 research outputs found
Combined Earth and Rock Bearing Foundation - Hospital Humana Mexico City D.F.
This text describes the design and performance of a shallow spread footing foundation system for a large medical care facility in Mexico City. The project is unusual because the spread footings bear on a combination of basaltic lava and coarse sand fill containing angular lava fragments, the latter of which was densified using the dynamic deep compaction process. In the following narrative, the exploratory program is described, the geotechnical design and construction process is explained, and the inspection procedure for footings bearing on rock and soil is discussed. Further, the results of precise settlement monitoring for the structure are presented
Evidence for topological defects in a photoinduced phase transition
Upon excitation with an intense ultrafast laser pulse, a symmetry-broken
ground state can undergo a non-equilibrium phase transition through pathways
dissimilar from those in thermal equilibrium. Determining the mechanism
underlying these photo-induced phase transitions (PIPTs) has been a
long-standing issue in the study of condensed matter systems. To this end, we
investigate the light-induced melting of a unidirectional charge density wave
(CDW) material, LaTe. Using a suite of time-resolved probes, we
independently track the amplitude and phase dynamics of the CDW. We find that a
quick (1ps) recovery of the CDW amplitude is followed by a slower
reestablishment of phase coherence. This longer timescale is dictated by the
presence of topological defects: long-range order (LRO) is inhibited and is
only restored when the defects annihilate. Our results provide a framework for
understanding other PIPTs by identifying the generation of defects as a
governing mechanism
Rent control simulation for Mexico City
A model, based in the current rent control legislation, of landlord's rent setting behavior is used to simulate rents that are then compared to an actual sample of rents from Mexico City. The paper assumes that landlords take into consideration the present value of future rent payments when setting new rents. This behavior nullifies the effects of rent control for the new tenant. Over a period of time tenants enter into a new contract and lose the benefits of the rent control law. The initial rents will be higher than what they would have been had there been no rent control. The main objective of the law, to reduce rents and to protect tenants against increases every year, is defeated after a period of time