scholarly journals POSSIBLE DEFECTS IN WOOD, WOOD PARAMETERS VARIABILITY AND SOME OF ITS INFLUENCE ON QUALITY OF BUILDING STRUCTURE

2015 ◽  
Vol 7 (2) ◽  
pp. 67-80
Author(s):  
Jaroslaw Malesza

Paper specifies the wood-framed with sheathing construction including phases of realization and exploitation. Methods of investigation based on practice and theory has been employed where practical identification of processes and their phases were presented with theoretical description of structure deformation within the exploitation period. Obtained results of investigations are presented in the form of technologic and mechanic of structure diagrams for buildings with adequate algorithms of analysis. Paper presents practical systematic of construction stages, technological problems and hazards in respect of loading and construction technology with method of computation of vertical deformations of building. Paper presents evaluation of contribution of wood defects in response to loading in the wood-framed residential building in exploitation process. Location of knots, allocation of pith in the elements cross section, defects of slope of grain and influence of moisture decreasing is examined in the paper. The wood-framed with sheathing in the form of large panel or modular three dimensional 3D elements are the most often used technology. This kind of buildings are actually constructed up to four story as a multifamily or varying universal buildings like school, kid-garden or offices. Low dead load from 0.30 to 1.00 kN/m2 and its favorable proportion to the live load increase energy saving factor in realization and within the exploitation time. Low own weight of structure enables complete prefabrication of wall, floor and roof panels, improving quality of construction and shortening time of construction. Process of prefabrication, wide assortment and variety of factory production does not require time consuming processes and complicated moulds or shuttering indispensable in precast RC structural elements.

Author(s):  
U. Herbig ◽  
I. Mayer ◽  
H. Mortada ◽  
S. Rasztovits

3D Laser scanning technology gained more and more importance for the recording and documentation of architectural heritage. Especially for the survey of heterogeneous surfaces and complex structures it is a fast and reliable option for survey and so appreciated sources for research in architecture. Therefore the integration of laser scanning as a part of the building survey became a kind of standard procedure for objects of different scale, shape, age and origin. <br><br> In some cases more than one team records an object with different devices using altering approaches. For example a client provides existing data from a part of the object that can't be accessed anymore, but is important to be integrated into the overall survey. The merging of the datasets may become challenging, especially if one survey is not documented in detail, in particular when it comes to the quality of the result. <br><br> For a research about the traditional architecture of Saudi Arabia a building in the historic part of Jeddah has been surveyed in detail by a team of researchers of the Vienna University of Technology. Within this frame a workshop for students of the King Abdul Aziz about building archaeological research has been conducted. As part of the results consists of two sets of laserscan data, recorded with different laser scanners. Using these data a possible approach for the registration of scan data from different and/or unknown provenance has been developed which will be outlined in this paper.


2021 ◽  
Vol 264 ◽  
pp. 02066
Author(s):  
Rustem Mukhametrakhimov ◽  
Indira Aliullova

Expansion joints play an important role in the operation of bridge construction. The reliability and durability of most of the other structural elements of the bridge depend on its quality and have a significant impact on road safety. One of the most effective types of expansion joints is rubber compensators, the service life of which directly depends on the quality of its installation. In this work, the types and classifications of expansion joints of bridge construction are studied, their defects and causes of their appearance are analyzed, a visual inspection of the state of expansion joints of the bridge is performed. The technology and quality control system of technological processes for constructing s single-profile expansion joints with rubber compensators during the repair of bridge construction is proposed.


Author(s):  
S. Khadpe ◽  
R. Faryniak

The Scanning Electron Microscope (SEM) is an important tool in Thick Film Hybrid Microcircuits Manufacturing because of its large depth of focus and three dimensional capability. This paper discusses some of the important areas in which the SEM is used to monitor process control and component failure modes during the various stages of manufacture of a typical hybrid microcircuit.Figure 1 shows a thick film hybrid microcircuit used in a Motorola Paging Receiver. The circuit consists of thick film resistors and conductors screened and fired on a ceramic (aluminum oxide) substrate. Two integrated circuit dice are bonded to the conductors by means of conductive epoxy and electrical connections from each integrated circuit to the substrate are made by ultrasonically bonding 1 mil aluminum wires from the die pads to appropriate conductor pads on the substrate. In addition to the integrated circuits and the resistors, the circuit includes seven chip capacitors soldered onto the substrate. Some of the important considerations involved in the selection and reliability aspects of the hybrid circuit components are: (a) the quality of the substrate; (b) the surface structure of the thick film conductors; (c) the metallization characteristics of the integrated circuit; and (d) the quality of the wire bond interconnections.


Author(s):  
B. Carragher ◽  
M. Whittaker

Techniques for three-dimensional reconstruction of macromolecular complexes from electron micrographs have been successfully used for many years. These include methods which take advantage of the natural symmetry properties of the structure (for example helical or icosahedral) as well as those that use single axis or other tilting geometries to reconstruct from a set of projection images. These techniques have traditionally relied on a very experienced operator to manually perform the often numerous and time consuming steps required to obtain the final reconstruction. While the guidance and oversight of an experienced and critical operator will always be an essential component of these techniques, recent advances in computer technology, microprocessor controlled microscopes and the availability of high quality CCD cameras have provided the means to automate many of the individual steps.During the acquisition of data automation provides benefits not only in terms of convenience and time saving but also in circumstances where manual procedures limit the quality of the final reconstruction.


2003 ◽  
Vol 70 ◽  
pp. 201-212 ◽  
Author(s):  
Hideaki Nagase ◽  
Keith Brew

The tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of the matrix metalloproteinases (MMPs), enzymes that play central roles in the degradation of extracellular matrix components. The balance between MMPs and TIMPs is important in the maintenance of tissues, and its disruption affects tissue homoeostasis. Four related TIMPs (TIMP-1 to TIMP-4) can each form a complex with MMPs in a 1:1 stoichiometry with high affinity, but their inhibitory activities towards different MMPs are not particularly selective. The three-dimensional structures of TIMP-MMP complexes reveal that TIMPs have an extended ridge structure that slots into the active site of MMPs. Mutation of three separate residues in the ridge, at positions 2, 4 and 68 in the amino acid sequence of the N-terminal inhibitory domain of TIMP-1 (N-TIMP-1), separately and in combination has produced N-TIMP-1 variants with higher binding affinity and specificity for individual MMPs. TIMP-3 is unique in that it inhibits not only MMPs, but also several ADAM (a disintegrin and metalloproteinase) and ADAMTS (ADAM with thrombospondin motifs) metalloproteinases. Inhibition of the latter groups of metalloproteinases, as exemplified with ADAMTS-4 (aggrecanase 1), requires additional structural elements in TIMP-3 that have not yet been identified. Knowledge of the structural basis of the inhibitory action of TIMPs will facilitate the design of selective TIMP variants for investigating the biological roles of specific MMPs and for developing therapeutic interventions for MMP-associated diseases.


1990 ◽  
Vol 18 (4) ◽  
pp. 216-235 ◽  
Author(s):  
J. De Eskinazi ◽  
K. Ishihara ◽  
H. Volk ◽  
T. C. Warholic

Abstract The paper describes the intention of the authors to determine whether it is possible to predict relative belt edge endurance for radial passenger car tires using the finite element method. Three groups of tires with different belt edge configurations were tested on a fleet test in an attempt to validate predictions from the finite element results. A two-dimensional, axisymmetric finite element analysis was first used to determine if the results from such an analysis, with emphasis on the shear deformations between the belts, could be used to predict a relative ranking for belt edge endurance. It is shown that such an analysis can lead to erroneous conclusions. A three-dimensional analysis in which tires are modeled under free rotation and static vertical loading was performed next. This approach resulted in an improvement in the quality of the correlations. The differences in the predicted values of various stress analysis parameters for the three belt edge configurations are studied and their implication on predicting belt edge endurance is discussed.


Author(s):  
Radhika Theagarajan ◽  
Shubham Nimbkar ◽  
Jeyan Arthur Moses ◽  
Chinnaswamy Anandharamakrishnan

1991 ◽  
Vol 28 (2) ◽  
pp. 257-265 ◽  
Author(s):  
D. F. Graham ◽  
D. R. Grant

Side-looking, C-band synthetic-aperture radar (SAR) penetrates cloud and fog, and operates day or night, to produce pseudo-three-dimensional terrain images with enhanced topography and surface roughness. The images, which have a 20 m resolution and cover large areas, have been used to map the regional trends, patterns of lineaments, and terrain types over a 6200 km2 area of complex lithology, structure, and drift cover. Four lineament classes are differentiated. Glacial trends are clear, and bedrock structures (faults, fractures, joints, foliation, and folded bedding) with relief expression at the surface show through the drift as lineaments. They accurately reproduce most known features when compared with bedrock and Quatenary geology maps. Hitherto unrecognized structural elements are revealed. Tones and textures reflect minute surface roughness variations useful in terrain classification. SAR wide-swath-mode imagery is thus a valuable complement to aerial photography, and is superior in revealing hummocky moraine, ribbed moraine, boulder fields and stony till. Wider use of this imagery is encouraged.


2019 ◽  
Vol 136 ◽  
pp. 04080
Author(s):  
Guohui Cao ◽  
Reqiang Liu ◽  
Jing Liu ◽  
Xiang Gao ◽  
Peng Wang

The complex three-dimensional traffic construction often occur when the lower structure cannot bear the construction load and other special cases, indicating the need for temporary reinforcement of the lower structure. In this paper, combined with a project construction example, various temporary reinforcement technologies are adopted to solve the insufficient bearing capacity during understructure construction, which poses a serious danger, to ensure synchronous construction of the understructure and viaduct. Compared with the traditional construction technology, the temporary reinforcement technology proposed in this paper features the advantages of saving project cost and time and has achieved better economic and social benefits.


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