In-situ Testing

This paper describes the instrumental methods for evaluating timber quality and condition, applied in the preparation for the White Tower belfry renovation in Hradec Králové. The belfry holds the third largest bell (8t) in the Czech Republic. Latest diagnostic equipment and methods (grips pushed apart in a borehole, resistance drilling and endoscopy) were used for the evaluation of the condition of individual structural elements made of oak. The evaluation of the current state of the historic structure primarily aimed to determine the position and dimensions of potential hidden defects (e.g. ends of binders or hidden pins of diagonal struts and posts). The outputs obtained using partially invasive instrumental methods could later be verified during the repairs of the belfry, which took place in 2014. The results of the methods used were found to be sufficiently accurate and appropriate for the diagnostics of potential damage as well as the determination of the mechanical properties of historically valuable timber elements. The repairs themselves used the knowledge and skills of traditional manual carpentry to a maximum possible degree. The project also benefited from the results obtained by the diagnostic methods, thanks to which oak wood could be prepared in advance. Wooden variations of traditional lap joints found their application in the extensions of partially damaged beams. The required quality of the newly used timber was achieved by hewing or manual cutting. The process of manual working was continuously monitored and the results are subjected to discussion in the paper. In order to reduce the costs of manipulation with the constructional elements at the site, a replica of a period winch with a roller was used to lift the material to the third floor of the tower.

Increasing use of the ground as a thermal reservoir is expected in the near future. Shallow geothermal energy (SGE) systems have proved to be sustainable alternative solutions for buildings and infrastructure conditioning in many areas across the globe in the past decades. Recently novel solutions, including energy geostructures, where SGE systems are coupled with foundation heat exchangers, have also been developed. The performance of these systems is dependent on a series of factors, among which the thermal properties of the soil play a major role. The purpose of this paper is to present, in an integrated manner, the main methods and procedures to assess ground thermal properties for SGE systems and to carry out a critical review of the methods. In particular, laboratory testing through either steady-state or transient methods are discussed and a new synthesis comparing results for different techniques is presented. In situ testing including all variations of the thermal response test is presented in detail, including a first comparison between new and traditional approaches. The issue of different scales between laboratory and in situ
measurements is then analysed in detail. Finally, the thermo-hydro-mechanical behaviour of soil is introduced and discussed. These coupled processes are important for confirming the structural integrity of energy geostructures, but routine methods for parameter determination are still lacking.

The East Port Said region, one of the most vibrant areas in the East Nile Delta, is a strategic economic zone that is receiving growing local and global investments. The near surface formations, however, typically comprise very soft clays deposited during the Holocene epoch. Collecting undisturbed samples and conducting laboratory evaluation of these sensitive soils could be cumbersome, inaccurate, and uneconomical. Therefore, the use of in-situ cone penetration test (CPT) provides a viable and convenient characterization alternative. This study attempts to establish site-specific correlations between the measurements of the static CPT and shear wave velocities (Vs) furnished by seismic piezocone soundings. The mathematical regressions were developed utilizing a number of measurements and factors, namely, tip resistance, sleeve friction, effective stress, depth, voids ratio, and soil behavior type index. The proposed correlations demonstrate different levels of predictability, with a few warranting confidence in employing static CPT for estimation of Vs profile in this region. Two correlations, one utilizing void ratio and tip resistance and the other employing sleeve friction solely, have shown to provide the most reliable Vs predictions for the soft clay in the East Nile Delta.