Shellac dan Gelatin untuk Konsolidasi Artefak Kayu

Wood is a hygroscopic organic material, prone to damage and weathering, especially by humidity. The moisture in the wood will trigger biotic activities such as fungus, which can decompose of wood materials, that is, cellulose. Moreover, wood is susceptible to insect attacks such as termites. This condition will cause the wood to become brittle so that the strength of the wood will decrease. To strengthen brittle wood, consolidation treatments are needed. Material for wood consolidation that has been used is Paraloid B72 with acetone solvent, which is not easy to find everywhere Materials tested for wood artifacts consolidations were shellac and gelatin with a concentration of 5%, 7,5%, and 10%. As a comparison, the material used for wood consolidation is Paraloid B72 10%. Test parameters used include SEM test, density test, compressive strength test, color change test, fungal growth observation, and FTIR test. Test results have shown that shellac 7,5% and 10% can be an alternative to Paraloid B72 as a wood artifacts consolidation material. Shellac 7,5% is the optimum concentration for wood artifacts consolidation because materials will be more efficient. This material can fill the wood pores and increase the density by 13,89%. The resulting compressive strength value reached 248,01 kg/cm2 or increased by 43,18%, higher than Paraloid B72 10%. Shellac 7,5% does not change the color of the wood and safe from fungal growth when applied to wood. This material also does not change the chemical composition of wood. Keywords: wood, artifact, consolidation, shellac, gelatin, Paraloid B72

Restauración y conservación de un conjunto de estelas de falsa puerta hallado en Heracleópolis Magna (Ehnasya el-Medina. Beni Suef)

An important set of false door stelae with polychrome and hieroglyphic inscriptions have been found, throughout several excavation campaigns, in the necropolis of the First Intermediate Period/Early Middle Kingdom at Herakleopolis Magna. A part of this set is preserved in the National Archaeological Museum (Madrid), while other stelae are stored in the Cairo Museum and in the warehouses of the Ministry of Antiquities located at Ehnasya el-Medina. The conservation and restoration of these objects was undertaken following the criteria recommended by national and international regulations and institutions. The works have been carried out in the National Archaeological Museum and the workshop of the Spanish Archaeological Mission in Ehnasya el-Medina. The stelae presented a heterogeneous and different state of conservation; while some were complete, others were in a fragmentary state. With the purpose of returning the stelae to their original morphology and identity, the treatments applied have essentially consisted of: cleaning, consolidation, material reintegration and volumetric recovery. After restoration, new interesting aspects about the necropolis and the people buried there have come to light.

Experimental Studies on Earthen Architecture Sites Consolidated with BS Materials in Arid Regions

This paper takes the preservation works on the archaeological sites of Gaochang Ruins, Xinjiang, as background. Based on the soil characteristics analysis on the archaeological sites, experimental studies were conducted on the consolidation effect of the BS-10 consolidation material on the archaeological sites of adobe and rammed earth. The results showed the following:, after consolidation, the wind erosion resistance of the soil on the archaeological sites was substantially increased, and the wind erosion modulus was reduced by 5~8 times; the soil exhibited fine grid structure and significantly reduced degree of permeability, while still maintaining the moisture exchange between inside and outside the soil; there is excellent ageing resistance; the resistance to freezing and thawing was closely related to the soil water content and had little influence in arid regions; the water resistance was improved and could satisfy the requirements for consolidating the sites in arid regions; the unconfined compressive strength was improved moderately, which was the key direction of improvement in the future, and the consolidated soil did not form duricrust on the surface and had good bonding strength with the internal parts. The BS-10 material can meet the consolidation requirements for the earthen archaeological sites in arid regions of northwest China.

Functional state of blood circulation and neuromuscular system of the lower limb of patients with congenital pseudarthrosis of the tibia after consolidation of the nonunion

The aim of this study was to evaluate the clinical and functional state of the neuromuscular system and the blood supply to the lower limbs of children with congenital pseudarthrosis of the tibia (CPT) after consolidation. Material and Methods. A total of 100 patients with CPT were analyzed. We performed a clinical examination of patients, panoramic X-ray of the lower extremities, electroneuromyogram, and reovasography. Results and Conclusions. The primary complaints of patients with CPT after the consolidation of the non-union were lameness, deformations of lower extremities, and pain in the local joints. The electromyoneuromyogram data of the lower limbs of patients with CPT exhibited a decrease of the contractility of the muscles of the lower limbs, and neuropathy of the peroneal nerves of both lower limbs. The reovasography data of the lower limbs of patients with CPT displayed improvement in blood circulation in the lower extremities after the consolidation of the tibia. These data promote the current methods of treatment of patients with CPT; however, the temperature, degree of limb lengthening, and deformity correction should be considered in the future.

Excavation Mechanics Analyses for Shield Tunnels Considering Consolidation Material Property Impacts

Current researches of material engineering give little investigations on the construction impacts of soil consolidation material property. Based on the Shanghai tunneling case, the excavation mechanics analyses for shield tunnels are conducted considering soil consolidation material property using 3D (three-dimensional) finite element numerical simulation method. The longitudinal deformation behaviors for existing tunnel after the completion of shield tunnel excavation are obtained under several typical cases of soil consolidation, including one month later, one year later, and ten years later. It is shown that the consolidation material property has a significant post-construction time effects on the vertical displacements of existing tunnels. The stringent stipulations on controlling the deformation for buried structures and strengthened monitoring measures are necessary and substantial for reducing potential service risks according to the post-construction state.

Microstructure Analysis of Soil Consolidation Material

Polymer modified straw fiber-reinforced cementitious composition（PSFC） prepared by polyacrylamide, straw fiber, industrial solid waste and cement, was a new type of and soil consolidation material. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to identify major chemical composition and structure of the matrix-fiber interface. The results show that the polyacrylamide can efficiently improve the structure of matrix-fiber transition zone, and water-soluble polymer mixing amount acts significantly on its existing morphology.

The Effect of Modified Straw on Microstructure of Soil Consolidation Material

The application of wheat straw fiber reinforced cement-based composites (WFCC) was restricted because of the poor mechanical properties and lots of extractives of wheat straw in cement paste. In order to overcome the natural defects, the wheat straw was modified respectively by different mass fractions of NaOH, Na2SiO3and H3PO4solutions. The results show that, the various indexes of wheat straw fiber soaked by NaOH solutions (mass fraction 5%) for 12 hours were optimal. Moreover, its ultimate tensile strength and fracture elongation were respectively increased by 104.81% and 78.57%. Meanwhile, the modified fiber bundles arranged densely without damage phenomenon in WFCC, and surface of fiber was covered in massive cement hydration products, and the interfacial adhesion between fiber and hardened cement paste was improved.