Measuring and Modelling the Reverberation of a Bare Rock Tunnel
نویسندگان
چکیده
Acoustic impulse responses of an excavated tunnel were measured. Analysis of the impulse responses shows that they are very diffuse from the start. A reverberator suitable for reproducing this type of response is proposed. The input signal is first comb-filtered and then convolved with a sparse noise sequence of the same length as the filter’s delay line. An IIR loop filter inside the comb filter determines the decay rate of the response and is derived from the Yule-Walker approximation of the measured frequency-dependent reverberation time. The particular sparse noise sequence proposed in this work combines three velvet noise sequences, two of which have time-varying weights. To simulate the directional soundfield in a tunnel, the use of multiple such reverberators, each associated with a virtual source distributed evenly around the listener, is suggested. The proposed tunnel acoustics simulation can be employed in gaming, in film sound, or in working machine simulators.
منابع مشابه
Application of Geostatistical Modelling to Study the Exploration Adequacy of Uniaxial Compressive Strength of Intact Rock alongthe Behesht-Abad Tunnel Route
Uniaxial compressive strength (UCS) is one of the most significant factors on the stability of underground excavation projects. Most of the time, this factor can be obtained by exploratory boreholes evaluation. Due to the large distance between exploratory boreholes in the majority of geotechnical projects, the application of geostatistical methods has increased as an estimator of rock mass pro...
متن کاملThe effect of engineering geology on the rock load and squeezing potential in Lot2 of Imamzadeh-Hashem tunnel
The load entering from the ground surrounding on the tunnel’s lining is one of the effective parameters in the designation of a tunnel. The amount of this parameter, which is called Rock load in a rocky environment, depends on several factors such as the overburden thickness, geological and geomechanical conditions and the depth of tunnel. In the present study, the amount of rock load for the L...
متن کاملCalculation of tunnel behavior in viscoelastic rock mass
Wall displacements and ground pressure acting on the lining of a tunnel increase with time. These time-dependent deformations are both due to face advance effect and to the time-dependent behavior of the rock mass. Viscoelastic materials exhibit both viscous and elastic behaviors. Thorough this study, the effect of different linear viscoelastic models including Maxwell, Kelvin and Kelvin-Voigt...
متن کاملEffects of statistical distribution of joint trace length on the stability of tunnel excavated in jointed rock mass
The rock masses in a construction site of underground cavern are generally not continuous, due to the presence of discontinuities, such as bedding, joints, faults, and fractures. The performance of an underground cavern is principally ruled by the mechanical behaviors of the discontinuities in the vicinity of the cavern. During underground excavation, many surrounding rock failures have close r...
متن کاملBehavior of a Tunnel and its Neighboring Joint with and without Presence of Rock Bolt under Biaxial Loads; Particle Flow Code Approach
In this work, the interaction between the semi-circular space and the neighboring joint with and without the presence of rock bolts was investigated using the particle flow code (PFC) approach. For this purpose, firstly, the calibration of PFC was performed using both the Brazilian experimental test and the uniaxial compression test. Secondly, a numerical model with the dimension of 100 m...
متن کامل