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This paper deals with the measurement of physical properties (mechanical, thermal, acoustical) of various formulations of concrete containing vegetable particles. Such material is mde up with hemp shives mixed with lime binders. Shives are very porous and so liglitweight. Thus, this concrete presents a high porosity related to the microscopic porosity of the shives and the macroscopic porosity due to the arrangement of particles. Moreover, this material presents a ductile behavior and can bears high strain without been destroyed. Depending on the binder proportion, the mechanical properties of vegetable concrete cover a wide range: maximum stress in between 0.4 and 1.2 MPa, Young madulus in between 20 and 90 MPa, strain at maximum stress in between 4 and 10%. The thermal conductivity ranges from 0.06 to 0.11 W.m-1.K-1, sound absorption between 0.5 and 1. The final aim of this study is to optimize the formulation of vegetable concrete according to its use (wall, floor, roof. . .). A theoretical model made with self-consistent method allows to calculate precisely the coefficient of conductivity l as a function of the mixture proportion and the compactness level. A comparison with experimental measurements shows a good accuracy of the results.

Recycled aggregates used in combination with high-volume fly ash is an example of sustainable construction material because it represents a judicious use of resources by recycling by-products, that results in a lower environmental impact through reduced carbon dioxide emissions and reduced natural aggregate extraction from quarries. Furthermore, the related concrete mixtuns yield satisfactory mechanical performance. The goal of the experimental work reported here was to investigate the effect of recycled aggregate andor fly ash on carbonation and chloride penetration depth, as well as the effect on corrosion behavior of either bare or galvanized steel in cracked reinforced concrete. The concrete mixture contained equal amounts of fly ash and cement. The results show that the introduction of the sustainability concept in concre&e trechnology by using recycled aggregate andor fly ash did not cause any deleterious effects on durability of reinforced concrete specimens in terms of both chloride and carbon dioxide penetration, and reinforcement corrosion in cracked concrete.

Completion of the Central A r t e r y b e l Project inchdes development of more that 20 distinct parcels along the original, elevated artery corridor. This paper presents challenges encountered during the design of Parcel 6, which is located between New Chardon and Sudbury Streets in Boston, Massachusetts. The Parcel 6 lid will cover five adjacent cast-in-place concrete boat section ramps. The final use of the lid is not yet known; however, since construction of the ramps is currently underway, the walls were re-designed to accommodate either a landscaped deck, or a five-story building. Design included both wind and seismic lateral analyses of the two types of potential lid structures, with the reinforcing in the ramp walls modified to accommodate both options in order to minimize impacts or retrofits requkd in the future. Changes to the original design included modifying wall heights and reinforcing, and inclusion of interim backwalls for temporary earth support. The landscaped option included preliminary designs of four separate deck structures, skewed portal beams, overhead impact attenuators, and a merge gore area. The building option presumed asymmetrical column loadings and locations, with a comparative analysis of column base shears used to determine maximum loading on the existing ramp walls.

Past Earthquakes have shown that flared columns are susceptible to pre- mature shear failures. In the 1999 Northridge Earthquake, Shear failures have been caused by a plastic hinge formation occurred at the base of the flare and a subsequent increase in the level of column shear demand above design levels. This paper presents an experimental and analytical study that is examining new details for flared columns and joints. The primary feature is a gap at the top of the column and the amount of transverse flare reinforcement. Two two-column bents were tested on the shake table to examine dynamic effects as well as column and beam interaction. The test specimens had different amounts of confining reinforcement in the flare. The detail proved an overall ductility that is above the minimum limit recommended by the current specifications. Test also showed that gap started to close at ductility level that is below the recommended limit.

On June 15, 1999, a magnitude Mw = 7.0 earthquake occurred with epicenter located southwest from the city of Tehuacan, Puebla, and on September 30, 1999, a Mw = 7.5 magnitude earthquake occurred with epicenter located northeast from the city of Puerto Escondido, Oaxaca, Mexico. The earthquakes affected a wide geographical area, including seven states. Few casualties were recorded. In Puebla, 15 percent in the State of Oaxaca and only the remaining ten percent in the States of Morelos, Mexico, Tlaxcala, Veracruz and Guerrero; the second earthquake only affected the State of Oaxaca. Historical buildings, dwellings, hospitals, schools and roads were mostly impacted. Some damages were also experienced in bridges and lifelines. The economic activities were not severely impaired. This paper summarizes the seismological characteristics of the event, its economic impact and the Emergency measures adopted by the authorities. Observation made during several visits to the affected regions of Puebla and Oaxaca on the behavior of soils and foundations, lifeline, schools, dwellings, historical monuments and commercial buildings are described. Recommendations for the development o fvulnerability reduction programs are presented.