Recovery of traditional mortars in the laboratory of materials at the school of architectura of Madrid

The Laboratory of Materials seminar is an optional course offered to students in the School of Architecture in Madrid. It is taught during 35 class hours in the laboratory of materials distributed in two hours and forty minutes weekly. One of the working lines is the preparation of traditional mortars made by students groups, each one of 4 or 5 members. It is basically a practical course, and students have to prepare a group of tests pieces in order to confirm the initial hypothesis, or when needed, make innovations. The test pieces are of 150mmx150mmx10mm and applied to big size hollow bricks, prismatic test pieces of 40mmx40mmx160mm to apply physical and mechanical tests and brick wallings of varied dimensions.

In situ acoustic methods to estimate the physical and mechanical aging of oriented strand board

Following the success achieved in previous research projects usin non-destructive methods to estimate the physical and mechanical aging of particle and fibre boards, this paper studies the relationships between aging, physical and mechanical changes, using non-destructive measurements of oriented strand board (OSB). 184 pieces of OSB board from a French source were tested to analyze its actual physical and mechanical properties. The same properties were estimated using acoustic non-destructive methods (ultrasound and stress wave velocity) during a physical laboratory aging test. Measurements were recorded of propagation wave velocity with the sensors aligned, edge to edge, and forming an angle of 45 degrees, with both sensors on the same face of the board. This is because aligned measures are not possible on site. The velocity results are always higher in 45 degree measurements. Given the results of statistical analysis, it can be concluded that there is a strong relationship between acoustic measurements and the decline in physical and mechanical properties of the panels due to aging. The authors propose several models to estimate the physical and mechanical properties of board, as well as their degree of aging. The best results are obtained using ultrasound, although the difference in comparison with the stress wave method is not very significant. A reliable prediction of the degree of deterioration (aging) of board is presented.

Non-destructive methods to estimate physical aging of plywood

This paper studies the relationship between aging, physical changes and the results of non-destructive testing of plywood. 176 pieces of plywood were tested to analyze their actual and estimated density using non-destructive methods (screw withdrawal force and ultrasound wave velocity) during a laboratory aging test. From the results of statistical analysis it can be concluded that there is a strong relationship between the non-destructive measurements carried out, and the decline in the physical properties of the panels due to aging. The authors propose several models to estimate board density. The best results are obtained with ultrasound. A reliable prediction of the degree of deterioration (aging) of board is presented.

Building from building waste: The development of an instrument to determine the circularity of materials from the existing building stock in order to maximise high quality reuse

On a global level the population growth and increase of the middle class lead to a growing demand on material resources. The built environment has an enormous impact on this scarcity. In addition, a surplus of construction and demolition waste is a common problem. The construction industry claims to recycle 95% of this waste but this is in fact mainly downcycling. Towards the circular economy, the quality of reuse becomes of increasing importance. Buildings are material warehouses that can contribute to this high quality reuse. However, several aspects to achieve this are unknown and a need for more insight into the potential for high quality reuse of building materials exists. Therefore an instrument has been developed that determines the circularity of construction waste in order to maximise high quality reuse. The instrument is based on three principles: ‘product and material flows in the end of life phase’, ‘future value of secondary materials and products’ and ‘the success of repetition in a new life cycle’. These principles are further divided into a number of criteria to which values and weighting factors are assigned. A degree of circularity can then be determined as a percentage. A case study for a typical 70s building is carried out. For concrete, the circularity is increased from 25% to 50% by mapping out the potential for high quality reuse. During the development of the instrument it was clarified that some criteria are difficult to measure. Accurate and reliable data are limited and assumptions had to be made. To increase the reliability of the instrument, experts have reviewed the instrument several times. In the long-term, the instrument can be used as a tool for quantitative research to reduce the amount of construction and demolition waste and contribute to the reduction of raw material scarcity.

Handbook of definitions of materials and end products used in "M" and "L" orders issued by the War production board through March 1, 1943.

Reproduced from typewritten copy.

Development of materials and public relations efforts to promote child passenger safety. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

The aging of the U.S. population [microform] : planning for the retirement and employment needs of older Americans : hearing before the Subcommittee on Retirement Income and Employment of the Select Committee on Aging, House of Representatives, One Hundredth Congress, second session, July 15, 1988, South Burlington, VT.

"Comm. pub. no. 100-686."

Accelerated aging of concrete : a literature review /

"February 2002."

Aging of Columbium Alloy D-43 [electronic resource]

Mode of access: Internet.

Investigation of materials for use in a heat transfer system containing liquid lead alloys, report no. XII : final report April 1, 1950 to June 30, 1951 /

"U. S. Government Printing Office: 1955."--P. 34.

Hazardous properties and environmental effects of materials used in solar heating and cooling (SHAC) technologies : interim handbook /

Issued Dec. 1978.

A compendium of the properties of materials at low temperatures (Phase 1- )

"Materials Central. Contract no. AF 33 (616)-58-4, Project no. 7360."