Vibratory Effects in Reinforced Portland Cement Concrete Pavement, MLR-97-2, 1997

A double mat of reinforcement steel consisting of No. 5 bars was placed in the longitudinal and transverse directions in a 26' wide, 10" thick pavement. The bars were placed on 12" centers with 2" of cover from the top and bottom surfaces. The special reinforcement is to provide additional strength in the pavement over an area of old coal mine tunnels. Auxiliary and standard paver vibrators were used to consolidate the concrete. There was concern that over-vibration could be occurring in some areas and also that a lack of consolidation may be occurring under the steel bars in some areas. A core evaluation study of the pavement was developed. The results showed that the consolidation and the air contents were satisfactory. Additional paving with reinforcement in the same area should use the same or similar method and amount of vibration as was used in the area evaluated in this study.

La formació dels nous mestres: revisió del pla d'estudis

Amb motiu de la publicació d'una sèrie d'artícles sobre les titulacions en Ciències de l'Educació de la Universitat de Barcelona, es revisen les condicions i les característiques dels estudiants per al mestre a partir dels resultats de diversos estudis desenvolupats per l'autor sobre aquest col·lectiu durant l'etapa 1993-1997

Testing of Old Reinforced Concrete Bridges, HR-390, 1997

The objective of this research project was to service load test a representative sample of old reinforced concrete bridges (some of them historic and some of them scheduled for demolition) with the results being used to create a database so the performance of similar bridges could be predicted. The types of bridges tested included two reinforced concrete open spandrel arches, two reinforced concrete filled spandrel arches, one reinforced concrete slab bridge, and one two span reinforced concrete stringer bridge. The testing of each bridge consisted of applying a static load at various locations on the bridges and monitoring strains and deflections in critical members. The load was applied by means of a tandem axle dump truck with varying magnitudes of load. At each load increment, the truck was stopped at predetermined transverse and longitudinal locations and strain and deflection data were obtained. The strain data obtained were then evaluated in relation to the strain values predicted by traditional analytical procedures and a carrying capacity of the bridges was determined based on the experimental data. The response of a majority of the bridges tested was considerably lower than that predicted by analysis. Thus, the safe load carrying capacities of the bridges were greater than those predicted by the analytical models, and in a few cases, the load carrying capacities were found to be three or four times greater than calculated values. However, the test results of one bridge were lower than those predicted by analysis and thus resulted in the analytical rating being reduced. The results of the testing verified that traditional analytical methods, in most instances, are conservative and that the safe load carrying capacities of a majority of the reinforced concrete bridges are considerably greater than what one would determine on the basis of analytical analysis alone. In extrapolating the results obtained from diagnostic load tests to levels greater than those placed on the bridge during the load test, care must be taken to ensure safe bridge performance at the higher load levels. To extrapolate the load test results from the bridges tested in this investigation, the method developed by Lichtenstein in NCHRP Project 12-28(13)A was used.

Performance of Randomly Oriented, Fiber-Reinforced Roadway Soils, HR-211, 1982

Several primary techniques have been developed through which soil aggregate road material properties may be improved. Such techniques basically involve a mechanism of creating a continuous matrix system of soil and/or aggregate particles, interlocked through the use of some additive such as portland cement, lime, or bituminous products. Details by which soils are stabilized vary greatly, but they are dependent on the type of stabilizing agent and nature of the soil, though the overall approach to stabilization has the common feature that improvement is achieved by some mechanism(s) forcing individual particles to adhere to one another. This process creates a more rigid material, most often capable of resisting the influx of water during freezing, loss of strength due to high moisture content and particle dispersion during thawing, and loss of strength due to migration of fines and/or water by capillarity and pumping. The study reported herein, took a new and relatively different approach to strengthening of soils, i.e., improvement of roadway soils and/or soil-aggregate materials by structural reinforcement with randomly oriented fibers. The purpose of the study was to conduct a laboratory and field investigation into the potential of improving (a) soil-aggregate surfaced and subgrade materials, including those that are frost-prone and/or highly moisture susceptible, and (b) localized base course materials, by uniting such materials through fibrous reinforcement. The envisioned objective of the project was the development of a simple construction technique(s) that could be (a) applied on a selective basis to specific areas having a history of poor performance, or (b) used for improvement of potential base materials prior to surfacing. Little background information on such purpose and objective was available. Though the envisioned process had similarities to fibrous reinforced concrete, and to fibrous reinforced resin composites, the process was devoid of a cementitious binder matrix and thus highly dependent on the cohesive and frictional interlocking processes of a soil and/or aggregate with the fibrous reinforcement; a condition not unlike the introduction of reinforcing bars into a concrete sand/aggregate mixture without benefit of portland cement. Thus the study was also directed to answering some fundamental questions: (1) would the technique work; (2) what type or types of fibers are effective; (3) are workable fibers commercially available; and (4) can such fibers be effectively incorporated with conventional construction equipment, and employed in practical field applications? The approach to obtaining answers to these questions, was guided by the philosophy that an understanding of basic fundamentals was essential to developing a body of engineering knowledge, that would serve as the basis for eventual development of design procedures with fibrous products for the applications previously noted.

Reinforced Slope with Geogrids, HR-548, 1997

The objective of this research study is to evaluate the performance, maintenance requirements and cost effectiveness of constructing reinforced slope along a concrete bikeway overpass with a Geogrid system such as manufactured by Tensar Corporation or Reinforced Earth Company. This final report consists of two separate reports - construction and performance. An earlier design report and work plan was submitted to the Iowa DOT in 1989. From the Design Report, it was determined that the reinforced slope would be the most economical system for this particular bikeway project. Preliminary cost estimates for other design alternatives including concrete retaining walls, gabions and sheet pile walls ranged from $204/L.F. to $220/L.F. The actual final construction cost of the reinforced slope with GEDGRIDS was around $112/L.F. Although, since the reinforced slope system was not feasible next to the bridge overpass because of design constraints, a fair cost comparison should reflect costs of constructing a concrete retaining wall. Including the concrete retaining wall costs raises the per lineal foot cost to around $122/L.F. In addition to this initial construction cost effectiveness of the reinforced slope, there has been little or no maintenance needed for this reinforced slope. It was noted that some edge mowing or weed whacking could be done near the concrete bikeway slab to improve the visual quality of the slope, but no work has been assigned to city crews. It was added that this kind of weed whacking over such steep slope is more difficult and there could possibly be more potential for work related injury. The geogrid reinforced slope has performed really well once the vegetation took control and prevented soil washing across the bikeway slab. To that end, interim erosion control measures might need to be considered in future projects. Some construction observations were noted. First, there i s no specialized experience or equipment required for a contractor to successfully build a low-to-medium geogrid reinforced slope structure. Second, the adaptability of the reinforced earth structure enables the designer to best fit the shape of the structure to the environment and could enhance aesthetic quality. Finally, a reinforced slope can be built with relatively soft soils provided differential settlements between facing are limited to one or two percent.

Bonded, Thin-Lift, Non-Reinforced Portland Cement Concrete Resurfacing, MLR-77-2, 1977

A research project involving 2, 3, 4, and 5 in. (5.1, 7.6, 10.2, and 12.7 cm) of bonded portland cement concrete (PCC) overlay on a 1.3 mile (2.1 km) PCC pavement was conducted in Clayton County, Iowa, during September 1977, centering on the following objectives: (1) Determine the mixing and proportioning procedures required in using a conventional, central mix proportioning plant to produce a dense PCC mixture using standard mixes with super water reducing admixtures; (2) Determine the economics, longevity and maintenance performance of a bonded, thin-lift, non-reinforced PCC resurfacing course using conventional procedures, equipment and concrete paving mixtures both with and without super water reducing admixtures; and (3) Determine if an adequate bond between the existing pavement and an overlay of thin-lift, dense, non-reinforced PCC can be obtained with only special surface cleaning and no surface removal or grinding. The conclusions are as follows: (1) Normal mixing equipment and proportioning procedures could be used using a conventional central-mix proportioning plant. This was successful when used with super water reducing admixtures. Only minor changes need be made in procedures and timing. (2) The time has been too short since the completion of the project to determine how the new pavement will perform, however, initially it appears that the method is economical and no reason is seen at this time why the life of the pavement should not be comparable to an all new pavement. (3) The initial test results show that bond strength, regardless of which method of cleaning is used, scarifying, sand blasting or water blasting, far exceed what is considered the minimum bond strength of 200 psi (1379 kPa) except where the paint stripes were intentionally left, thus showing that the paint must be removed. (4) It appears that either cement and water grout or sand, cement and water grout may be used and still obtain the required bond.

Retaining Wall - Modular Unit Reinforced Earth Tensar Geogrid Reinforcement, HR-549, 1998

This research, initiated in October 1992, was located at the intersection of Blairs Ferry Road and Lindale Drive in the City of Marion. The wall is located on the southeast corner of the intersection. Reinforced retaining wall construction started with a five inch base of roadstone with one inch of sand for leveling purposes. One and one-half to two feet of one inch clean stone was placed behind the blocks. A four inch perforated plastic pipe was placed approximately nine inches from the bottom of the one inch clean stone. The Tenswal, tensar geogrid was placed at every third layer. Openings in the Tenswal are hooked over plastic dowels in the blocks. The tenswal reaches from the face of the wall back 5' to 8'. The cost for constructing this wall was $124,400. The wall has performed well for the past five years. The wall improves the aesthetics of a high traffic volume intersection of an urban area. Many positive comments have been received by the city regarding its appearance. The City of Marion has been pleased with the wall and has used this type of wall on subsequent projects.

Bonded, Thin-Lift, Non-Reinforced Portland Cement Concrete Resurfacing, HR-191, 1980

A Research Project involving two, three, four and five inches of bonded Portland Cement Concrete Overlay on a 1.3 mile Portland Cement Concrete pavement was conducted in Clayton County, Iowa, during September, 1977, centering on the following objectives: 1. Determine the mixing and proportioning procedures required in using a conventional, central mix proportioning plant to produce a dense Portland Cement Concrete mixture using standard mixes with super-water reducing admixtures; 2. Determine the economics, longevity and maintenance performance of a bonded, thin-lift, non-reinforced Portland Cement Concrete resurfacing course using conventional procedures, equipment and concrete paving mixtures both with and without super-water reducing admixtures; 3. Determine if an adequate bond between the existing pavement and an overlay of thin-lift, dense, non-reinforced Portland Cement Concrete can be obtained with only special surface cleaning and no surface removal or grinding.

Reinforced Earth and Stone Columns for Weak Subsoil Conditions, HR-510, 1980

Reinforced Earth is a French development that has been used in the United States for approximately ten years. Virbro-Replacement, more commonly referred to as stone columns, is an outgrowth of deep densification of cohesionless soils originally developed in Germany. Reinforced Earth has applicability when wall height is greater than about twelve feet and deep seated foundation failure is not a concern. Stone columns are applicable when soft, cohesive subsoil conditions are encountered and bearing capacity and shearing resistance must be increased. The conditions in Sioux City on Wesley Way can be summarized as: (1) restricted right of way, (2) fill height in excess of 25 feet creating unstable conditions, (3) adjacent structures that could not be removed. After analyzing alternatives, it was decided that Reinforced Earth walls constructed on top of stone columns were the most practical approach.

Pla d'acollida per a la integració d'adolescents i joves nouvinguts a la ciutat de Sant Boi de Llobregat

L'estudi que presentem té com a primer objectiu conèixer en profunditat les necessitats dels i les adolescents i joves immigrats i la realitat actual dels diferents serveis per a donar resposta a aquestes necessitats. Un segon objectiu ha estat elaborar conjuntament amb els agents socials i les entitats de Sant Boi un pla d'acollida per facilitar la integració d¿aquests adolescents i joves, així com la coordinació dels diferents agents, entitats i serveis municipals. Per aquest motiu es planteja una investigació col·laborativa amb diferents agents i entitats representatius del teixit social de la població, i amb els/les tècnics/iques de les diferents regidories de l'Ajuntament (joventut, serveis socials, nova ciutadania, participació i educació). Els objectius generals de la investigació són els següents: a) fer una anàlisi de necessitats dels i les adolescents i joves immigrants de la població de Sant Boi amb referència a la seva participació social; b) realitzar un estudi diagnòstic de l'acollida d¿adolescents i joves immigrants en el teixit associatiu i social en el municipi de Sant Boi de Llobregat; c) elaborar un pla d'acollida integral per als i les adolescents i joves nouvinguts a la ciutat de Sant Boi. El disseny de la investigació segueix les fases d¿una avaluació participativa. Al llarg del procés s'ha treballat de forma consensuada entre l'equip de recerca i els agents socials de la zona: Administració pública i entitats d'iniciativa social. L'anàlisi de necessitats i la diagnosi de l'atenció socioeducativa dels i les joves immigrats s'ha desenvolupat a través de dos instruments de recollida d'informació: un qüestionari per als i les joves, fonamentat en un model dinàmic de ciutadania i una entrevista semiestructurada als agents socials de la zona. Les conclusions, les hem classificat segons els eixos i àmbits del nou Programa municipal transversal per a nova ciutadania de Sant Boi i en forma de propostes a partir de les necessitats detectades.

Pla d'acollida per a la integració d'adolescents i joves nouvinguts a la ciutat de Sant Boi de Llobregat

L'estudi que presentem té com a primer objectiu conèixer en profunditat les necessitats dels i les adolescents i joves immigrats i la realitat actual dels diferents serveis per a donar resposta a aquestes necessitats. Un segon objectiu ha estat elaborar conjuntament amb els agents socials i les entitats de Sant Boi un pla d'acollida per facilitar la integració d¿aquests adolescents i joves, així com la coordinació dels diferents agents, entitats i serveis municipals. Per aquest motiu es planteja una investigació col·laborativa amb diferents agents i entitats representatius del teixit social de la població, i amb els/les tècnics/iques de les diferents regidories de l'Ajuntament (joventut, serveis socials, nova ciutadania, participació i educació). Els objectius generals de la investigació són els següents: a) fer una anàlisi de necessitats dels i les adolescents i joves immigrants de la població de Sant Boi amb referència a la seva participació social; b) realitzar un estudi diagnòstic de l'acollida d¿adolescents i joves immigrants en el teixit associatiu i social en el municipi de Sant Boi de Llobregat; c) elaborar un pla d'acollida integral per als i les adolescents i joves nouvinguts a la ciutat de Sant Boi. El disseny de la investigació segueix les fases d¿una avaluació participativa. Al llarg del procés s'ha treballat de forma consensuada entre l'equip de recerca i els agents socials de la zona: Administració pública i entitats d'iniciativa social. L'anàlisi de necessitats i la diagnosi de l'atenció socioeducativa dels i les joves immigrats s'ha desenvolupat a través de dos instruments de recollida d'informació: un qüestionari per als i les joves, fonamentat en un model dinàmic de ciutadania i una entrevista semiestructurada als agents socials de la zona. Les conclusions, les hem classificat segons els eixos i àmbits del nou Programa municipal transversal per a nova ciutadania de Sant Boi i en forma de propostes a partir de les necessitats detectades.

La Mina. Pla d'Accions de Barri en Espai Públic

Este documento desarrolla el conjunto de planteamientos abordados en el proceso de participación ciudadana: Cartografies de La Mina 2002-2006. http://www.ub.edu/escult/mina

Identificació de les competències més valorades en l'entorn professional i adequació del pla d'estudis de grau en enginyeria informàtica

L'execució d'aquest projecte ha volgut reflectir quines són les capacitats professionals més valorades actualment, poder entendre quines són les condicions actuals i reflexionar sobre quina és la cobertura que els plans educatius actuals -en l'àmbit de l'enginyeria informàtica- brinden a aquesta evolució, contribuint amb aquest estudi a l'objectiu general de l'àrea de competències professionals d'apropar el món acadèmic al laboral.

Aprèn 4rt. Pla estratègic. Biblioteques UPC. 2007-2010

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digital¡. 5è Pla estratègic de les Biblioteques UPC. 2012-2014

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