TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Experimental soil parameters by different evaluation methods for impulsive, train and ambient excitation T2 - 5th Int. Symp. on Environmental Vibration (ISEV) CY - Chengdu, China DA - 2011-10-20 PY - 2011 AN - OPUS4-24738 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Schmid, Wolfgang A1 - Wuttke, Wilfried T1 - Messung von Neigungen zur Ermittlung der Einflusslinie der Gärtnerplatzbrücke in Kassel T2 - Seminar: Monitoring Gärtnerplatzbrücke, Universität Kassel CY - Kassel, Germany DA - 2008-05-27 PY - 2008 AN - OPUS4-18142 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Environmental vibration due to normal and extreme extreme excitation: railway traffic, explosions and heavy mass drop tests T2 - ISEV 2007, Intern. Symposium on Environmental Vibration CY - Taipei, Taiwan DA - 2007-11-28 PY - 2007 AN - OPUS4-18239 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Environmental vibrations due to different technical sources, amplitude-distance laws in experiment and theory T2 - ISEV 2009 - International Symposium Environmental Vibration: Prediction, Monitoring and Evaluation CY - Beijing, China DA - 2009-10-28 PY - 2009 AN - OPUS4-20421 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Vibration measurements for the control of damaged and repaired railway tracks N2 - Measurements comparing the damaged and the repaired status of the same track section at different times, or a damaged and an intact track section at the same time have been successfully performed and compared with the theoretical behavior of intact and damaged tracks. The loose of contact between the sleeper and the plate, between the plate and the base layer, due to train passages and hammer impacts, have been investigated. T2 - 7th International Symposium on Environmental Vibration and Transportation Geodynamics CY - Hangzhou, China DA - 28.10.2016 KW - Railway track KW - Slab track KW - Field tests KW - Track damage monitoring KW - Finite element method KW - Boundary element method PY - 2016 AN - OPUS4-38275 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir T1 - Structural health monitoring by division 7.2, buildings and structures N2 - BAM is one of the pioneers in Germany and Europe regarding the monitoring of civil structures. BAM-Division 7.2 operates its monitoring systems with sophisticated components for data acquisition and data analysis, which can be flexibly adapt to the respective structure and measuring tasks. The BAM monitoring systems have been operated on numerous bridges (steel, concrete, pre-stressed concrete and masonry), buildings, towers, masts, monuments, wind turbines and other structures. In 1999, BAM established a national standard 'Automated continuous monitoring in civil engineering'. This has been internationalized within the framework of the EU research project SAMCO "F08b Guideline for Structural Health Monitoring". BAM-Division 7.2 is interested in international cooperation with Chinese partners. T2 - SEMINARS AT SHENZHEN GRADUATE SCHOOL OF HIT CY - Shenzhen, China DA - 02.11.2016 KW - Structural health monitoring (SHM) KW - Load-carrying capacity KW - Structural analyses KW - Damage detection PY - 2016 AN - OPUS4-38277 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir T1 - Brückenmonitoring 7.2 T2 - 20 jährige Dauerüberwachung der Westendbrücke CY - Berlin, Deutschland DA - 2015-09-23 PY - 2015 AN - OPUS4-34340 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Prediction of explosion-induced ground and building vibrations - measured wave velocities, transfer functions and attenuation N2 - Explosion-induced ground vibrations have been measured at several places. Results about the wave propagation are shown in this contribution. The particle velocities of the soil have been measured at up to 1000 m distance from the explosion and are presented as time records (seismograms) and one-third octave band spectra (transfer functions). The results are compared with the results of hammer impacts. The seismograms clearly show different wave types, compressional waves of the air, the water and the soil, and the Rayleigh wave. The hammer impacts yield good results up to 100 m and incorporate higher frequencies at about 50 Hz, whereas the explosion results in a ground vibration with frequencies around 10 Hz and a longer range of influence. Explosion and hammer excitations are evaluated for the wave velocities of the soil by using the wavenumber and the spatial auto-correlation method. The attenuation of the ground vibration amplitudes A with distance r can well be presented by a power law A ~ r -q. This type of amplitude-distance law and the corresponding power q > 1 are substantiated in the contribution. The influence of the charge weight W is evaluated as an additional power law A ~ W -p for each measuring site. The power is found quite similarly around q  0.6 as all sites have a medium soft soil such as sand and clay. The obtained amplitude-charge-distance law can be used to predict the explosion-induced ground and building vibrations at other sites. T2 - International Congress on Sound and Vibration (ICSV25) CY - Hiroshima, Japan DA - 08.07.2018 KW - Soil properties KW - Amplitude-charge weight laws KW - Amplitude-distance laws KW - Explosion-induced ground vibrations KW - Hammer impact KW - Prediction of explosion induced ground and building vibration PY - 2018 AN - OPUS4-45508 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Said, Samir A1 - Auersch, Lutz T1 - Measurement of slab track behaviour at different sites N2 - Measured train passages and hammer impacts in combination with track-soil calculation have been successfully used for the detection of damaged slab tracks. This approach is now extended to intact slab and ballast tracks. The vibrations of many tracks have been measured at several levels from rail, sleeper, track plate, base plate, base layer to the subsoil by velocity or acceleration sensors. The time histories have to be integrated once or twice to get the displacements. The displacement signals include an arbitrary time-dependent shift which must be eliminated or respected in the interpretation. On the other hand, the calculation of slab and ballast tracks have been done in frequency-wavenumber domain. The displacements along the track and the frequency-dependent compliance transfer functions can be calculated. The latter can be compared with the results of the hammer impacts on the track. The deformation of the track can be transformed to time histories for a whole train and compared to the measured train passages. Many slab (and ballast) tracks have been measured at different sites. The displacements of the tracks are presented, and the following parameters have been analysed in the measurement results: slab track vs. ballast track, different types of slab tracks, damaged slab tracks, different trains, switches at different measuring points, an elastic layer, the mortar layer, different soils at different places. The soil should have the dominant influence on the track-plate displacements. Slab and ballast track yield also big differences in maximum displacement and width of deformation. Some of the preceding aspects will be analysed in comparison of measurement and theory. T2 - 26th International Congress on Sound and Vibration (ICSV26) CY - Montreal, Canada DA - 07.07.2019 KW - Displacements KW - Train passage KW - Slab track KW - Hammer impact KW - Vibration measurements PY - 2019 AN - OPUS4-48495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Said, Samir A1 - Zhu, Shaocheng T1 - Dynamic testing of track damage before and after construction, after damage and after repair N2 - The Federal Institute of Material Research and Testing (BAM) has collected some experience with the testing of damaged, repaired and newly constructed railway tracks. The experimental methods are hammer testing of the track at different positions, hammer testing of the soil, measurement of train passages, and in all cases, measurements with geophones at different positions. The measured signals are evaluated for wave velocities (dispersion of the soil or the track-soil system), for transfer functions (transfer admittances of the soil, compliances of the track in amplitude and phase), and one-third octave band spectra of the track response to hammer and train excitation. These methods are applied at different stages of the track construction. Before track construction, wave velocities and transfer functions of the sub-soil can indicate problems with soft soils. After track construction, a check of the acceptable state of the track can be done by comparison of many excitation positions and track sites. After a track damage (a lose sleeper or a lose plate of a slab track) and after its repair, the sensitivity of the different measurement quantities to different track errors and the achieved improvement of the repair can be determined. The contribution shows examples of all these track situations T2 - Int. Conf. on Rail Transportation CY - Chengdu, China DA - 10.07.2017 KW - Track damage KW - Dynamic testing KW - Hammer tests KW - Train passages PY - 2017 AN - OPUS4-42490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -