scholarly journals Installation of stainless metal reinforcements in stone cultural monuments

St open ◽  
2021 ◽  
Vol 2 ◽  
pp. 1-17
Author(s):  
Jure Balić ◽  
Siniša Bizjak
Keyword(s):  
Stainless Steel ◽  
Structural Stability ◽  
Chemical Properties ◽  
Steel Structure ◽  
Standing Position ◽  
Steel Reinforcement ◽  
Basic Material ◽  
Free Standing ◽  
Stone Monuments ◽  
Cultural Monuments

Objective: To provide examples of the installation of stainless-steel reinforcements in a stone cultural monument as part of conservation and restoration work. Methods: During conservation and restoration works, metal elements in stone monuments are replaced by stainless steel, which shares the same physical properties as, for example, iron, but its chemical properties are much superior. Estimates of appropriate reinforcement, technical drawings and a detailed plan are drafted before the installation of stainless-steel reinforcements in the stonework itself. For more demanding calculations and designs, structural and other engineers and architects were consulted to obtain the optimal dimensions of structural elements. Results: The presented examples of stone monuments (an ancient stone sarcophagus, two ancient sculptures, one medieval portal, two baroque baptismal fonts and a baroque bell gable) were reinforced with stainless steel. A reinforcing mesh was utilized to connect fragments of the sarcophagus and reconstruct the missing parts. The sculptures were found in fragments and required steel reinforcement to be set up in a free-standing position. The baptismal fonts were also found in fragments due to the corrosion of their iron clamps; they were furnished with a detachable, externally invisible steel reinforcement. The medieval portal was at risk of collapse due to the static instability caused by the rupture of its load-bearing lintel. The lintel was reinforced with a steel bar, which absorbs compression forces acting on the stone superstructure. The baroque bell gable was a prime example of a monument damaged by its iron clamps. These were completely removed and the structural stability was secured by embedding a reversible steel structure in the stonework. Conclusion: Good physical and chemical properties make stainless steel the basic material in the reinforcement of stone cultural monuments. Its application in the conservation and restoration of stone monuments is currently the best and most efficient solution for restoring sustainable structural stability, original appearance and optimal positioning of monuments, as well as preventing further deterioration.

Body balance in a free-standing position in road and off-road cyclists

2014 ◽  
Vol 6 (4) ◽  
Author(s):  
Paulina Hebisz ◽  
Rafal Hebisz ◽  
Marek Zaton
Keyword(s):  
Sagittal Plane ◽  
Standing Position ◽  
The Body ◽  
Free Standing ◽  
Body Balance ◽  
Eyes Closed ◽  
Road Cycling ◽  
Progressive Exercise ◽  
Before And After ◽  
Road Cyclists

AbstractBackground: The purpose of this study was to compare body balance in road and off-road cyclists, immediately before and after the racing season.Material/Methods: Twenty individuals participated in the study and they were divided into two groups: specialists in road-cycling (n = 10) and in off-road cycling (n = 10). Immediately before and after the five-month racing season stabilographic trials were carried out (at rest and after progressive exercise). In assessing body balance the distance and velocity of the centre shifts (in the anterior-posterior and left-right direction) were analysed. The tests were performed with the cyclists’ eyes open, eyes closed, and in feedback.Results: After the racing season, in the off-road cyclists’ group, distance and velocity of the centre of pressure shifts increased after a progressive exercise.Conclusions: In the off-road cyclists’ group the balance of the body in the sagittal plane deteriorated after the racing season. Moreover, after the racing season off-road cyclists were characterized by a worse balance of the body, compared to road cyclists

Effects of galvanic mastoid stimulation in seated human subjects

2009 ◽  
Vol 106 (3) ◽  
pp. 893-903 ◽  
Author(s):  
Z. Ghanim ◽  
J. C. Lamy ◽  
A. Lackmy ◽  
V. Achache ◽  
N. Roche ◽  
...  
Keyword(s):  
Human Subjects ◽  
Normal Subjects ◽  
Standing Position ◽  
Reflex Response ◽  
Emg Activity ◽  
Free Standing ◽  
Vestibular Response ◽  
Vestibular Reflex ◽  
Tendon Jerk ◽  
Biphasic Responses

The vestibular responses evoked by transmastoid galvanic stimulation (GS) in the rectified soleus electromyogram (EMG) in freely standing human subjects disappear when seated. However, a GS-induced facilitation of the soleus monosynaptic (H and tendon jerk) reflex has been described in few experiments in subjects lying prone or seated. This study addresses the issue of whether this reflex facilitation while seated is of vestibulospinal origin. GS-induced responses in the soleus (modulation of the rectified ongoing EMG and of the monosynaptic reflexes) were compared in the same normal subjects while freely standing and sitting with back and head support. The polarity-dependent biphasic responses in the free-standing position were replaced by a non-polarity-dependent twofold facilitation while seated. The effects of GS were hardly detectable in the rectified ongoing voluntary EMG activity, weak for the H reflex, but large and constant for the tendon jerk. They were subject to habituation. Anesthesia of the skin beneath the GS electrodes markedly reduced the reflex facilitation, while a similar, although weaker, facilitation of the tendon jerk was observed when GS was replaced with purely cutaneous stimulation, a tap to the tendon of the sternomastoid muscle, or an auditory click. The stimulation polarity independence of the GS-induced reflex facilitation argues strongly against a vestibular response. However, the vestibular afferent volley, insufficient to produce a vestibular reflex response while seated, could summate with the GS-induced tactile or proprioceptive volley to produce a startle-like response responsible for the reflex facilitation.

scholarly journals Impact of Marine Bacterial Adhesion on the Physico-chemical Properties of Stainless Steel Surfaces

2019 ◽  
Vol 13 (1) ◽  
pp. 50-57
Author(s):  
Douaae Ou-yahia ◽  
Kawtar Fikri-Benb ◽  
Yassir Lekbach ◽  
Fadoua Bennouna ◽  
Hassan Barkai ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Bacterial Adhesion ◽  
Chemical Properties ◽  
Physico Chemical ◽  
Steel Surfaces

scholarly journals Free-standing spider silk webs of the thomisid Saccodomus formivorus are made of composites comprising micro- and submicron fibers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Christian Haynl ◽  
Jitraporn Vongsvivut ◽  
Kai R. H. Mayer ◽  
Hendrik Bargel ◽  
Vanessa J. Neubauer ◽  
...  
Keyword(s):  
Spider Silk ◽  
Structural Integrity ◽  
Chemical Properties ◽  
Free Standing ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
Crab Spiders ◽  
Ambush Predators ◽  
The Web ◽  
And Chemical Properties

Abstract Our understanding of the extraordinary mechanical and physico-chemical properties of spider silk is largely confined to the fibers produced by orb-weaving spiders, despite the diversity of foraging webs that occur across numerous spider families. Crab spiders (Thomisidae) are described as ambush predators that do not build webs, but nevertheless use silk for draglines, egg cases and assembling leaf-nests. A little-known exception is the Australian thomisid Saccodomus formivorus, which constructs a basket-like silk web of extraordinary dimensional stability and structural integrity that facilitates the capture of its ant prey. We examined the physical and chemical properties of this unusual web and revealed that the web threads comprise microfibers that are embedded within a biopolymeric matrix containing additionally longitudinally-oriented submicron fibers. We showed that the micro- and submicron fibers differ in their chemical composition and that the web threads show a remarkable lateral resilience compared with that of the major ampullate silk of a well-investigated orb weaver. Our novel analyses of these unusual web and silk characteristics highlight how investigations of non-model species can broaden our understanding of silks and the evolution of foraging webs.

scholarly journals Effect of no tillage on the physico-chemical properties of soils of the El Koudia region, Rabat (Morocco)

2020 ◽  
Vol 150 ◽  
pp. 03010
Author(s):  
Hassnae Maher ◽  
Rachid Moussadek ◽  
Abdelmjid Zouahri ◽  
Ahmed Douaik ◽  
Houria Dakak ◽  
...  
Keyword(s):  
Organic Matter ◽  
Structural Stability ◽  
Plant Cover ◽  
Chemical Properties ◽  
Aggregate Stability ◽  
Agricultural Practices ◽  
Conventional Tillage ◽  
No Tillage ◽  
Physico Chemical ◽  
Chemical Properties Of Soils

In Morocco, agriculture is an important sector of the economy, accounting for 15 to 20% of Gross Domestic Product. However, it has faced several challenges: intensive tillage of land that has accelerated water erosion, seriously threatening water and soil potential, low plant cover density and misuse of traditional agricultural practices, causing a decrease in organic matter levels and destroying aggregate stability. Climate change is making water and soil management in agriculture more and more complicated. The major challenge for Moroccan agriculture is to increase agricultural production while preserving natural resources. The objective of our study is to evaluate the effect of no tillage (NT) on the physico- chemical properties of soil in the El Koudia experimental station, Rabat, Morocco. The crop is durum wheat, Arrehane variety. Soil samples are pre-dried, ground and screened to 0.2mm for organic matter (OM) analysis and 2mm for the remainder of the analyses. Plugs, canned, are then sintered, screened and dried for structural stability tests. The results show that no tillage (NT) favours the accumulation of surface OM, particularly at the 0-5cm horizon unlike conventional tillage (CT). The NT promotes structural stability, with a mean weight diameter (MWD) = 0.94mm for the NT compared to 0.83mm for the CT. These results show that soils ploughed in CT are more exposed to erosion degradation than soils not ploughed (NT). In addition, NT preserves soil moisture and promotes additional water retention of 5 to 10%.

The stainless steel structure of a sport stadium in Quart

2002 ◽  
pp. 1: 547-556 ◽  
Author(s):  
Luis Sanchez Cuenca
Keyword(s):  
Stainless Steel ◽  
Steel Structure
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