In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of adobe.The opportunity for a new mo...In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of adobe.The opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).展开更多
A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the ...A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://doi.org/10.1016/j.dt.2018.07.017).Reply to the Note from Li Piani et al is linked to this article.展开更多
This paper will discuss experiments using various forming systems combined with utilizing mechanical equipment,from cement mixers to excavators and skid steers with attachments,to accelerate construction of cob homes ...This paper will discuss experiments using various forming systems combined with utilizing mechanical equipment,from cement mixers to excavators and skid steers with attachments,to accelerate construction of cob homes and greatly reduce the labor involved.Cob is a colloquial term for monolithic adobe,and refers to a masonry building technique used since ancient times that uses locally-sourced clay as a binder,with various aggregates from sand to small grit or stone,woven together with straw or other fiber and built in continuous layers to form a monolithic structure.展开更多
Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented ...Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented RH and to evaluate their influence on the behavior of raw earth for application in plaster. The influences of two types of RH are evaluated: granular rice husk (RHg) and powdered RH (RHp). The clay mainly consists of clay (40%), silt (22%), and sand (38.4%), with a small proportion of gravel (0.24%). Its liquidity limit is 40% and the plasticity index is 26.5%. The mixtures were designed using earth and each of the two rice husks at the volumetric content of 10%, 15% and 20% of the total volume mixed with water 36.5%, 38.5% and 40.3% and fermented for three weeks. Each fermented mixture was added to the soil to form the paste, and 40 × 40 × 160 mm<sup>3</sup> test speciments were made for characterization. The results generally show an improvement in the physico-mechanical properties and water resistance of the mortars containing fermented RH, with an optimal content between 10% and 15%. The powdered RH improved the performance of the mortar better than granular RH.展开更多
The housing sector today uses elaborate materials such as cement,iron,sand,often prohibitively expensive and whose production generates a strong environmental impact(scarcity of resources,transport,greenhouse gas gree...The housing sector today uses elaborate materials such as cement,iron,sand,often prohibitively expensive and whose production generates a strong environmental impact(scarcity of resources,transport,greenhouse gas greenhouse,etc.).In order to meet the challenges of sustainable development,earth construction is experiencing a resurgence of interest these days.Despite its many advantages,raw earth material has drawbacks,in particular its low mechanical resistance and its loss of geometric characteristics in the face of water,which slow down its development.As part of this study,the mechanical characteristics and durability of raw earth were improved by using residual water from the processing of Parkia Biglobosa(nere)and Vitellaria Paradoxa(shea)nuts in order to optimize its use for the construction of modern buildings.To this end,the decoctions resulting from the artisanal transformation of the nut of the Parkia Biglobosa into African mustard and of the Vitellaria Paradoxa into shea butter were added to the raw earth according to volume proportions of 25%,50%,75%and 100%of the aqueous solution to obtain the projected composites.Thus,mechanical characterization and durability tests were carried out on the composites obtained.The results revealed that the decoctions of Vitellaria Paradoxa and Parkia Biglobosa improve the compressive strength of the material by up to 90%and 260%,respectively.Furthermore,these decoctions improved the resistance to water penetration of the 100%additive composite by 1.5 times for Vitellaria Paradoxa and 5 times for Parkia Biglobosa.This study shows that it is possible to use decoctions as raw earth stabilizers to build modern,ecological buildings at lower energy costs.However,more in-depth studies on surface wettability and long-term durability are planned to better characterize the geomaterial.展开更多
随着新媒体时代的来临,对会议照片的质量要求越来越高。掌握对会议照片后期的快速处理能力,能够切实提高工作效率和效果。本文通过分析会议照片的特点,结合Adobe Camera Raw软件提出了一套具有普适性的后期思路,并通过实例进行说明展示...随着新媒体时代的来临,对会议照片的质量要求越来越高。掌握对会议照片后期的快速处理能力,能够切实提高工作效率和效果。本文通过分析会议照片的特点,结合Adobe Camera Raw软件提出了一套具有普适性的后期思路,并通过实例进行说明展示。随着新媒体的兴起,照片在各类宣传、汇报中的占比越来越大,会议照片成为了每个单位必不可少的重要图像资料。根据拍摄者、拍摄条件、会议场地的不同,原片会出现各种各样的问题。掌握一定的图像后期处理能力,可以修正这些问题,使最终存档的照片达到使用标准,对会议资料的整理和后续使用有很大的帮助。展开更多
文摘In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of adobe.The opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).
文摘A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://doi.org/10.1016/j.dt.2018.07.017).Reply to the Note from Li Piani et al is linked to this article.
文摘This paper will discuss experiments using various forming systems combined with utilizing mechanical equipment,from cement mixers to excavators and skid steers with attachments,to accelerate construction of cob homes and greatly reduce the labor involved.Cob is a colloquial term for monolithic adobe,and refers to a masonry building technique used since ancient times that uses locally-sourced clay as a binder,with various aggregates from sand to small grit or stone,woven together with straw or other fiber and built in continuous layers to form a monolithic structure.
文摘Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented RH and to evaluate their influence on the behavior of raw earth for application in plaster. The influences of two types of RH are evaluated: granular rice husk (RHg) and powdered RH (RHp). The clay mainly consists of clay (40%), silt (22%), and sand (38.4%), with a small proportion of gravel (0.24%). Its liquidity limit is 40% and the plasticity index is 26.5%. The mixtures were designed using earth and each of the two rice husks at the volumetric content of 10%, 15% and 20% of the total volume mixed with water 36.5%, 38.5% and 40.3% and fermented for three weeks. Each fermented mixture was added to the soil to form the paste, and 40 × 40 × 160 mm<sup>3</sup> test speciments were made for characterization. The results generally show an improvement in the physico-mechanical properties and water resistance of the mortars containing fermented RH, with an optimal content between 10% and 15%. The powdered RH improved the performance of the mortar better than granular RH.
基金supported by the Beninese state.An author received a trainer training grant from the Benin state for stays in the Jean Lamour Institute Laboratory of the University of Lorraine in France to carry out tests.
文摘The housing sector today uses elaborate materials such as cement,iron,sand,often prohibitively expensive and whose production generates a strong environmental impact(scarcity of resources,transport,greenhouse gas greenhouse,etc.).In order to meet the challenges of sustainable development,earth construction is experiencing a resurgence of interest these days.Despite its many advantages,raw earth material has drawbacks,in particular its low mechanical resistance and its loss of geometric characteristics in the face of water,which slow down its development.As part of this study,the mechanical characteristics and durability of raw earth were improved by using residual water from the processing of Parkia Biglobosa(nere)and Vitellaria Paradoxa(shea)nuts in order to optimize its use for the construction of modern buildings.To this end,the decoctions resulting from the artisanal transformation of the nut of the Parkia Biglobosa into African mustard and of the Vitellaria Paradoxa into shea butter were added to the raw earth according to volume proportions of 25%,50%,75%and 100%of the aqueous solution to obtain the projected composites.Thus,mechanical characterization and durability tests were carried out on the composites obtained.The results revealed that the decoctions of Vitellaria Paradoxa and Parkia Biglobosa improve the compressive strength of the material by up to 90%and 260%,respectively.Furthermore,these decoctions improved the resistance to water penetration of the 100%additive composite by 1.5 times for Vitellaria Paradoxa and 5 times for Parkia Biglobosa.This study shows that it is possible to use decoctions as raw earth stabilizers to build modern,ecological buildings at lower energy costs.However,more in-depth studies on surface wettability and long-term durability are planned to better characterize the geomaterial.
文摘随着新媒体时代的来临,对会议照片的质量要求越来越高。掌握对会议照片后期的快速处理能力,能够切实提高工作效率和效果。本文通过分析会议照片的特点,结合Adobe Camera Raw软件提出了一套具有普适性的后期思路,并通过实例进行说明展示。随着新媒体的兴起,照片在各类宣传、汇报中的占比越来越大,会议照片成为了每个单位必不可少的重要图像资料。根据拍摄者、拍摄条件、会议场地的不同,原片会出现各种各样的问题。掌握一定的图像后期处理能力,可以修正这些问题,使最终存档的照片达到使用标准,对会议资料的整理和后续使用有很大的帮助。
