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The purpose of this study is to fit an appropriate mathematical model to express response variables as functions of the proportions of the mixture components. One purpose of statistical modeling in a mixture experiment is to model the blending surface such that predictions of the response for any mixture component, singly or in combination, can be made empirically. Testing of the model adequacy will also be an important part of the statistical procedure.

A series of mortar using air lime, marble and ceramic sanitary waste aggregates were prepared for statistically designed combinations. The combinations were designed based on the mixture-design concept of design of experiments; this mortar is often used as a filler material in restoration projects. The aim of this work is to find an optimal composition of a paste for the manufacture of air lime mortar with ceramic and marble waste. This investigation aims to recommend mix design for air lime-based mortar, by optimizing the input combination for different properties, and to predict properties such as mechanical strength, thermogravimetric and x-ray diffraction analysis with a high degree of accuracy, based on a statistical analysis of experimental data.

This paper discusses those mortar properties that architects, contractors and owners consider important. For each of these properties, the influence of ceramic and marble waste in the air lime mortar is explored. The flexibility of lime-based mortars with waste materials to meet a wide range of needs in both new construction and restoration of masonry projects is demonstrated.

The objective of the present investigation is to recommend mixture design for air lime mortar with waste, by optimizing the input combination for different properties, and to predict properties such as compressive strength, flexural strength with a high degree of accuracy, based on the statistical analysis of experimental data. The authors conducted a mixture design study that takes into account dependent parameters such as the constituents of our air lime-based mortar where we have determined an experiment matrix to which we have connected the two responses, namely, compressive and flexural strength. By introducing the desirability criteria of these two responses, using JMP software, we were able to obtain a mixture optimal for air lime mortar with ceramic and marble waste.

The purpose of this paper is to characterize the properties lightweight green air lime and marble waste mixtures, relating microstructural and chemical properties with physical development of the material, an effort has been made to simulate the structure of the different mortar reinforced by two main layers plants.

This paper presents an experimental design of response surface methodology, a model which predicts the mechanical strength and evaluate the effectiveness of bio-waste as a corrosion inhibitor to resist the steel corrosion in air lime mortars as a function of the proportion of the constituents of a new air lime mortar based on a combination of different percentages of marble waste (MRW), air lime and deferent type, layers of natural fiber reinforcement. Luffa sponge gourd and oakum hemp fiber residues capabilities in civil engineering are evaluated by combining numerical and experimental approaches for repair mortar based on air lime and marble waste. Several electrochemical techniques, mechanical strength tests and visual inspection of steel surface were performed.

The results revealed good mechanical strength and corrosion protection properties of air lime mortar containing the fiber naturel. These green wastes are considered economically feasible, as well having possessing good performance efficiency in protecting rebar reinforcement. These results were confirmed via polarization curves and electrochemical impedance spectroscopy measurements.

The prepared green air lime mortar provided good corrosion protection to the rebar. The significance of this study is to encourage the usage of solid white marble waste to prepare biomass-based repair mortar with good mechanical and anti-corrosion properties on the long term is still a big challenge.

Dwellings constructed before 1920 often had solid brick walls with poor thermal performance. Today there is a drive to reduce both energy demand and carbon dioxide production. The purpose of this paper is to demonstrate that mixtures of chopped hemp straw with lime based binders added to the external surface of brick walls can substantially reduce the air to air thermal transmittance, or U‐value W/m² K, and that these mixtures provide a sustainable remedial treatment for solid brick walls. The aim is to achieve wall U‐values as good as, or better than, the current UK Building Regulations design value of 0.30 W/m² K.

Several Microsoft Excel spread sheets have been constructed to determine the steady state and transient thermal properties of various brick walls. These spread sheets are validated by comparing their output with the published thermal data to be found in the CIBSE Design Guide. The sustainable aspects of a number of different externally hemp‐lime insulated Victorian brick walls are described and discussed.

The U‐values and the transient thermal properties of solid brick walls with thickness 110 mm, 220 mm and 340 mm are presented. The transient properties include the admittance, decrement factor and lag time. These walls are then considered with various added external layers of hemp‐lime ranging in thickness from 50 mm to 300 mm. Some solid brick walls have an added air cavity, created with studding and plywood sheathing, before the layer of hemp‐lime. Walls with external tile hanging for sites with high exposure to driving rain are also discussed.

The paper demonstrates the advantages of the energy saving and carbon dioxide sequestration achieved by adding 200 mm of a hemp‐lime binder insulation to the exterior of Victorian brick walls of terraced dwellings.

The purpose of this research is to highlight issues relating to binder migration in traditional lime mortars and the potential consequences of this phenomenon. The paper focuses on traditional mass masonry construction and will be of special interest to those surveying, maintaining and repairing historic ruinous structures and heavily exposed masonry bridges.

The paper draws on literature pertaining to the repair of traditional mass masonry structures and the somewhat limited science of binder dissolution and migration in saturated conditions. The paper also draws on the author's practical and academic knowledge of writing specifications for the repair of mass masonry structures and utilises examples of binder migration from several case study buildings.

The degree to which binder migration in traditional mortars occurs is little understood. It is, however, evident that migration of the binder occurs when saturated conditions are present and is exacerbated by prolonged moisture ingress. The effect of binder migration on the stability and performance of mass masonry structures is also little understood and requires greater attention. In addition, the nature of the repair mortars specified and the degree to which these materials have set will have a bearing on the potential for binder migration.

An assessment of binder migration in traditional lime mortars and its effect on the stability and performance of mass masonry structures has never previously been undertaken. This paper is the first to highlight the problem.

The purpose of this paper is to present a proposal for a methodology to support the rehabilitation project of renders of old buildings.

To achieve the objective it was considered essential to define the main types of participants and aspects to integrate the proposal. The research methodology consists in an inquiry presented to several professional participants in rehabilitation, a market study of materials and products available in Portugal, the design of a methodology proposal and its application to a case study. The inquiry sample totals 24 answers from the targeted professionals. A sequence of relevant supporting procedures consists in the proposal, which aims to provide a supporting methodology to decide and project in this context and also to be tested with its application to the building. This proposal was applied to an old building with load-bearing stone masonry walls and air-lime-based renders.

It was concluded that the assessment of the building and ex+ternal renderings’ condition, its diagnosis and of the supporting walls, the definition of intervention, the specification of materials to be used and performance requirements to comply, and also plans for conservation and periodic maintenance, are crucial. From the inquiry, compatibility between materials and complementary roles and points of view of different types of participants in rehabilitation must be highlighted.

A proposal for a methodology to support the project could provide useful guidance particularly for architects and construction engineers, and improve the understanding of direct participants on site, therefore contributing for the correct implementation of the intervention.

The paper aims to evaluate drying performance of earth mortar by solar drying for more durability, minimize pathologies in traditional construction and determine the influence of temperature and humidity on the microstructure of earth mortar using static gravimetric method.

A convective solar dryer was used for the pretreatment of building and solid materials for construction.

The humidity influences the mortar sorption – surface water sorption of earth mortar increased with increasing temperature.

The study used a novel method for pretreatment building materials by using solar dryer.

The purpose of this study is to advance the application of pulverised cow bone ash (PCBA) as a partial replacement of cement in soil stabilisation for the production of bricks. The study investigated the impact of PCBA substitution on the characteristic strength of clay bricks under variant curing media.

Dried cow bones were pulverised, and an energy-dispersive X-ray fluorescence test was conducted on PCBA samples to determine the chemical constituents and ascertain the pozzolanic characteristics. Ordinary Portland cement (OPC) and PCBA were blended at 100%, 75%, 50%, 25% and 0% of cement substitution by mass to stabilise lateritic clay at 10% total binder content for the production of bricks. The binder-to-lateritic clay matrixes were used to produce clay bricks and cylinders for compressive and splitting tensile strength tests, respectively.

The study found that PCBA and OPC have similar chemical compositions. The strength of the clay bricks increased with curing age, and the thermal curing of clay bricks positively impacted the strength development. The study established that PCBA is a suitable substitute for cement, up to 25% for stabilisation in clay brick production.

Construction stakeholders can successfully use a PCBA-OPC binder blend of 1:3 to stabilise clay at 10% total binder content for the production of bricks. The stabilised clay bricks should be cured at an elevated temperature of approximately 90°C for 48 h to achieve satisfactory performance.

The PCBA-OPC binder blend provides adequate soil stabilisation for the production of clay bricks and curing the clay bricks at elevated temperature. This aspect of the biomass/OPC binder blend has not been explored for brick production, and this is important for the reduction of the environmental impacts of cement production and waste from abattoirs.

IN the October number of THE BRITISH FOOD JOURNAL, while disclaiming any intention of supporting or opposing any political party or any section of politicians, we stated our opinion that the fiscal policy which has been outlined before the country by Mr. CHAMBERLAIN is eminently one which requires to be put to the test of experiment and which cannot be profitably argued about upon theoretical bases. In connection with the allegation that by following the policy of leaving our doors open to those who shut their own doors in our faces, we are able to obtain goods at less expense than would be the case under other conditions, we pointed out that it would be well for the public to consider whether that which is so cheap may not also, to a great extent, be particularly nasty. The desirability of considering the nature and quality of so‐called “ cheap ” foods, supplied to us by various countriies without restriction, does not, as yet, appear to have entered the heads of those who have made matter for political controversy out of what is, in reality, a scientific question. The facts are not sufficiently known, or, in consequence of the proverbial carelessness of our generation, are not clearly appreciated. And yet, as it seems to us, some of those facts are of paramount importance to those who desire to study the subject in a calm and scientific manner and outside the region of political turmoil. What do we get from the various countries whose producers and merchants are free to “dump” their goods in this country without the restrictive influence of duty payments? Great Britain has made it known to all the world that “Rubbish may be Shot Here,” and we venture to say that the fullest advantage has been taken, and is taken, of the permission. From America, France, Germany, Italy, Holland, and Belgium, in fact from every producing country—including now even Russia and Siberia, we get inferior or scientifically‐adulterated articles which are sold to the public “ cheap.” Milk and butter scientifically adulterated, or produced under improper conditions in such a way that their composition becomes the same as physically‐adulterated products, condensed “milk” minus cream, cheese practically devoid of fat, or “ filled ” (as it is called) with margarine, all reach us in enormous quantities from most of our near and dear neighbours. Butter and certain wines and beers, loaded with injurious ‘ preservative” chemicals and the sale of which is prohibited in the country of production, are sent to the easily‐entered British “dumping‐ground” for the delectation of its confiding inhabitants. “Tinned” foods prepared from raw materials of inferior character or of more than questionable origin, are copiously unloaded on our shores to feed our complaisant population,—instead of being consigned to the refuse destructors which should be their proper destination; while, every now and then, when something worse than usual has been supplied, representative specimens of this delectable class of preparation are proved to have caused outbreaks of violent illness—those so‐called ptomaine poisonings which, of late years, have increased in number and in virulence to so distinctly alarming an extent. Flour made from diseased or damaged grain, or itself “ sick ” or damaged, and so “ processed ” as to mask its real condition; flour, again, adulterated with other and inferior meals, are “ goods ” supplied to us in ample amount for the benefit of those whose mainstay is some form of bread or flour‐food. The list might be continued literally ad nauseam.

The purpose of this paper is to analyse two parameters relevant to the physical‐mechanical performance of external renders, mainly, bulk density and apparent or open porosity, by performing laboratory tests on samples collected under real in‐service conditions.

The test procedure (sample preparation and techniques used) and its relationship with the overall performance characteristics and with any anomalies are discussed for each parameter. The analysis of the results covers seven case studies and 15 walls with renders made on site (cementitious and cement‐lime based) and non‐traditional or pre‐mixed renders.

It was concluded that reliable relationships could be established between the test results and other physical parameters relevant to the mechanical and water‐related behaviour of different types of cementitious renders. Notwithstanding the usual drawbacks of laboratory tests (more time‐consuming, higher costs and greater destruction of the walls), the use of small samples and the additional data obtained in terms of in‐service performance justify the use of this type of test.

The originality of this approach comes from the advantage of conducting both laboratory tests (reliability and standardization) and in situ tests (testing real materials subjected to in‐service conditions). Current practice is either to test virgin materials in quasi‐perfect laboratory conditions (therefore far from reality) or to test materials on site using standard in situ techniques sensitive to subjectivity and in far from ideal environmental conditions.

The PROCESS OF MAKING WIRE by drawing operations through dies, as distinct from hammering, though believed to be several thousand years old, until the last century was performed only by man‐, horse‐ or water‐power, so that production was slow and small. These old methods could not meet the greatly increased demand that then arose for wire of all kinds, such as copper wire for electrical purposes, and consequently power‐driven multi‐die benches were developed. Drawing speeds were still limited to several hundreds of feet per minute because of the rapid wear of the chilled iron and steel dies then used; but with the introduction of tungsten carbide dies and diamond dies, speeds were again increased, and now figures of 2,000 ft. per minute for steel wire, and 5,000 ft. per minute or more for copper and aluminium, are commonplace. These advances have required improved drawing lubricants, and future increases in drawing speeds likewise largely depend on improving lubricants still further. The general problem is to provide adequate lubrication for long die life, coupled with the intensive cooling that higher drawing speeds compel.