Tunnel Area Research Articles

Determination of 2,4,6 – trinitrotoluene in the soil samples around the Cu Chi Tunnel area by gas chromatography – mass spectrometry

During Vietnam War, nitroaromatic compounds such as 2,4,6-trinitrotoluene (TNT) have been widely used many kinds of explosive which bombed the immense network of connecting underground tunnels in Cu Chi District, Ho Chi Minh City, Vietnam. This study aims to optimize the method of using gas chromatography − mass spectrometry (GC-MS) to analyze TNT and then apply it to determine TNT in soil samples which collected around the Cu Chi area tunnels. In this experiment, ultrasonic was used to extract TNT from the soil samples to Acetonitrile before injecting 1µL sample solution into GC-MS. This method had linear concentration range of TNT from (5.0 to 500) ng/ g with limit of detection was 2.0 ng/g, the relative standard deviations of peak area were under 2.0 % and the recovery was from 80 % to 103 %. The results showed that TNT contamination in studied soil samples were not detected.
 ® 2023 Journal of Science and Technology - NTTU

Clinical features and surgical treatment of combination of pronator teres syndrome and carpal tunnel syndrome

Objective: To determine the effectiveness of surgical interventions aimed at decompression of the median nerve (MN) in the carpal tunnel and pronator teres canal, in combination with carpal tunnel syndrome (CTS) and pronator teres syndrome (PTS). Materials and methods: The results of surgical treatment of patients with a combination of CTS and PTS were analyzed, a total of 20 observations. The analysis of the results was evaluated according to: the Boston Questionnaire (BCTQ), namely, symptoms severity scale - SSS (minimum 1 point, maximum 5 points) and functional severity scale - FSS (minimum 1 point, maximum 5 points), the Bishop Score, visual analogue scale (VAS). Results: All operated patients (100%) experienced a significant regression of the main manifestations of the disease on the first day after the operation. Paresthesia in the fingers of the hand decreased, the sensitivity in the MN dermatome improved significantly, and sleep improved. The average indicators after surgery on symptoms severity scale (SSS) were 1.3 points, on functional severity scale (FSS) - 1.4 points, visual analogue scale - 2 points. The assessment of treatment results according to the Bishop Score in the postoperative period, that is, at the time of discharge (3 days after surgery), was an average of 10 points. Conclusions: Decompression of the MN in the area of the carpal tunnel and pronator teres is an effective method of treatment for the combination of CTS and PTS. A positive effect in the form of a regression of pain syndrome, sensitivity disorders and an increase in strength in the hand is observed already in the early postoperative period. Scores on BCTQ and VAS improve by more than 50%.

Carpal Tunnel Syndrome: Neuropathic Pain Associated or Not with a Nociplastic Condition.

Carpal tunnel syndrome (CTS) has been traditionally classified as primarily a neuropathic condition with or without pain. Precision medicine refers to an evidence-based method of grouping patients based on their susceptibility to biology, prognosis of a particular disease, or in their response to a specific treatment, and tailoring specific treatments accordingly. In 2021, the International Association for the Study of Pain (IASP) proposed a grading system for classifying patients into nociceptive, neuropathic, or nociplastic phenotypes. This position paper presents data supporting the possibility of subgrouping individuals with specific CTS related-pain into nociceptive, neuropathic, nociplastic or mixed-type phenotypes. Carpal tunnel syndrome is a neuropathic condition but can also be comorbid with a nociplastic pain condition. The presence of extra-median symptoms and the development of facilitated pain processing seem to be signs suggesting that specific CTS cases can be classified as the nociplastic pain phenotype. The clinical responses of therapeutic approaches for the management of CTS are inconclusive. Accordingly, the ability to identify the predominant pain phenotype in patients with CTS could likely be problematic for producing efficient treatment outcomes. In fact, the presence of a nociplastic or mixed-type pain phenotype would explain the lack of clinical effect of treatment interventions targeting the carpal tunnel area selectively. We propose a clinical decision tree by using the 2021 IASP classification criteria for identifying the predominant pain phenotype in people with CTS-related pain, albeit CTS being a priori a neuropathic pain condition. The identification of a nociplastic-associated condition requires a more nuanced multimodal treatment approach to achieve better treatment outcomes.

Analysis and Prediction of the Factors Influencing Postconstruction Surface Deformation of Pipe-Jacking Tunnel in Soft Clay Strata in China

During the postconstruction operation period, the engineering structure and operation safety of a pipe-jacking tunnel are more likely to be threatened by the surrounding environment and groundwater when it is located in a soft clay stratum. Surface settlement data related to the construction of 24 rectangular pipe-jacking tunnels in a soft clay stratum in China were collected and analyzed to determine the effect of pipe-jacking tunnel engineering on its deformation based on factors such as structural section form, geotechnical condition, groundwater condition, and buried depth. The postmaximum surface settlement and postformation loss rate were obtained, the correlation coefficients between the postsurface deformation of soft clay strata and various influencing factors were calculated using a software for correlation analysis, and the variation rules for each influencing factor were explored in depth. Subsequently, multiple linear regression methods were used to predict the maximum surface deformation of the pipe-jacking tunnel project in soft clay strata during the postoperation period, and actual engineering cases were verified and analyzed. The results show that the relative buried depth of the pipe-jacking tunnel in soft clay stratum has the greatest influence on the postmaximum ground settlement, followed by the section area of the pipe-jacking tunnel, and the relative height coefficient of groundwater level has the least influence. Under the reduction coefficient of 0.937 − 0.846, a new prediction formula for surface settlement deformation after the construction of the soft clay layer was derived. The error between the formula and the measured data was 9.05%, which can be used as a reference for controlling design parameters to predict the settlement after construction of pipe-jacking engineering.

Influence of Rock Layer Thickness on the Penetration Resistance of a Composite Target

To describe the influence of rock thickness on the penetration resistance of rock-concrete composite targets, a three-dimensional model was simulated using the nonlinear dynamic simulation software LS-DYNA. The penetration of four composite targets with rock-concrete thicknesses of 10-20, 20-20 cm, 30-20 and 40-20 cm by a projectile at a target angle of 75 degrees is investigated in this study. A damage cloud diagram of the target plate is obtained, and the curves of penetration speed and overload in the X and Y directions of the projectile with time are analysed. During penetration, the rock and concrete layers tend to restrain each other from destroying the target’s back and surface, and the projectile directly enters the tunnel area of the concrete layer from the tunnel area of the rock layer. When the ratio of rock thickness to shot length is less than 1.5, the attitude of the projectile after penetrating the composite target is relatively stable.

Experimental Research on the Settlement Feature of Two Ground Deformation Modes Induced by Tunnelling

Two ground deformation modes, i.e., the arching mode and collapsing mode, may be caused by tunnel excavation. However, the development of the ground deformation corresponding to the two modes is unclear. A piece of a model test facility is designed to study the ground settlement induced by tunnel excavation. Tunnel excavation is realized by decreasing the area of the model tunnel. Two model tests with different soil cohesion are conducted, and the two ground deformation modes form in the two tests, respectively. The former mode is observed at higher soil cohesion while the latter is found to develop at lower soil cohesion. Whether the failure surface develops to the ground surface or not is the most significant difference between the two ground deformation modes. In the two modes, the failure surface occurs at the position where the ground settlement contours distribute densely, and the shape of the failure surface can be described by the semi-oval for both modes. Meanwhile, for both the arching mode and the collapsing mode, Gaussian curves can reasonably describe the ground settlement troughs before the ground surface settlement becomes stable or increases sharply, and distribution of the trough width parameter is similar.

DIAGNOSTIC VALUE OF MEDIAN NERVE CONDUCTION VELOCITY ACROSS WRIST AMONG PATIENTS WITH SUSPECTED CARPAL TUNNEL SYNDROME

Background: Carpal Tunnel Syndrome (CTS) is the most prevalent type of compressive neuropathy. At present, electrodiagnosis is considered the gold standard in diagnosing CTS. However, no clear cutoff point has been established regarding the diagnostic value of the median nerve conduction velocity, across the carpal tunnel area, among patients with CTS.
 Objectives: This study aimed to determine the cutoff point for patients’ median nerve conduction velocity (NCV), to diagnose CTS among suspected patients, which is determined using electrical stimulations conducted across the carpal tunnel area. The present study also aimed to determine the diagnostic value of the median nerve conduction velocity across the carpal tunnel area, compared with the standard method.
 Methods: This cross-sectional study was conducted among 56 participants (106 wrists) suspected of CTS. Motor and sensory NCV across the carpal tunnel was investigated to yield diagnostic value of CTS compared with the standard technique.
 Results: The optimal cutoff point in diagnosing CTS using the wrist to midpalm conduction velocity, was 40 m/s (with a sensitivity of 87.04% and specificity of 87.18%) for the sensory nerve conduction study, and 35 m/s (with a sensitivity of 88.06% and specificity of 89.74%) for the motor nerve conduction study.
 Conclusion: Our study determined that the optimal cutoff conduction velocities for CTS diagnosis, using the wrist-to-midpalm electrical stimulation method, was 40 m/s for the sensory nerve, and 35 m/s for the motor nerve.

Single-Use Negative Pressure Wound Therapy Applied on Various Wound Types: An Interventional Case Series.

The purpose of this study was to determine whether a single-use negative pressure wound therapy (NPWT) system achieves individualized goals of therapy when used to treat patients with a variety of wound types. Multiple case series. The same comprised 25 participants; their mean age was 51.2 years (SD: 18.2; range: 19-79 years); 14 were male (56%) and 11 were female (44%). Seven study participants withdrew from study participation. Wound etiologies vary; 4 had diabetic foot ulcers; 1 had a full-thickness pressure injury; 7 were treated for management of an abscess or cyst; 4 had necrotizing fasciitis, 5 had nonhealing postsurgical wounds, and 4 had wounds of other etiologies. Data were collected at 2 ambulatory wound care clinics located in the Southeastern United States (Augusta and Austell, Georgia). A single-outcome measure was selected for each participant by his or her attending physician at a baseline visit. Selected end points were (1) decrease in wound volume, (2) decrease in size of the tunneling area, (3) decrease in size of the undermining, (4) decrease in the amount of slough, (5) increase in granulation tissue formation, (6) decrease in periwound swelling, and (7) wound bed progression toward transition to another treatment modality (such as standard dressing, surgical closure, flap, or graft). Progress toward the individualized goal was monitored until the goal was achieved (study end point) or a maximum of 4 weeks following initiation of treatment. The most common primary treatment goal was to achieve a decrease in wound volume (22 of 25 study participants), and the goal to increase granulation tissue was chosen for the remaining 3 study participants. A majority of participants (18 of 23, 78.3%) reached their individualized treatment outcome. The remaining 5 participants (21.7%) were withdrawn during the study (for reasons not related to the therapy). The median (interquartile range [IQR]) duration of NPWT therapy was 19 days (IQR: 14-21 days). Between baseline and the final assessment, median reductions in wound area and volume were 42.7% (IQR: 25.7-71.5) and 87.5% (IQR: 30.7-94.6). The single-use NPWT system achieved multiple individualized treatment objectives in a variety of wound types. Individually selected goals of therapy were met by all study participants who completed the study.

Influence of Blasting Disturbance on the Dynamic Stress Distribution and Fracture Area of Rock Tunnels

In order to study the dynamic stress distribution and the fracture area of rock around the tunnel under different orientations of blasting disturbance, AUTODYN finite difference method software was used to conduct numerical simulation research. Gauge monitoring points were set around the numerical model of the tunnel to conduct real-time monitoring of the stress distribution, displacement and fracture area of the tunnel. Based on the analysis of the stress wave propagation law, the following conclusions are obtained: (1) under the condition of the same blasting loads, the stress and displacement of the tunnel is relatively small when the blasting disturbance source is located above the roof, i.e., the stress state of the tunnel is relatively stable and the fracture area around the tunnel is minimal; (2) from the uniaxial stress around the tunnel and the tunnel peripheral displacement, it can be seen that the displacement caused by horizontal direction stress of the tunnel is the largest, and the deformation is mainly concentrated above the floor and at the shoulder, while the vertical wall part has almost no deformation; (3) for brittle materials such as rock, the arch-shaped stress-bearing surface is more likely to disperse stress, while the straight wall and flat floor of the tunnel cannot well disperse stress, resulting in uneven stress on the stress-bearing surface, uncoordinated deformation and ultimately, failure.

Geophysical research of underground hydraulic structures, old Glubochinsky water tunnel case study

Research objective is to study the features of geophysical fields and parameters in the area of the artificial underground water tunnel and estimate the capabilities of geophysical methods of identifying hidden underground industrial facilities. Methods of research. Measurements of self-potential signals (SP) were carried out using nonpolarizing electrodes and an electrical exploration receiver. The magnetic exploration was carried out by a proton magnetometer. Electrotomography was carried out using multielectrode electrical survey equipment with a Schlumberger symmetrical scheme of surveys. The microseismic background was recorded using an autonomous seismic station. The georadar survey was carried out using the SIR-3000 ground penetrating radar and antennas with the frequencies of 100 MHz and 270 MHz. Results. Based on the survey results, graphs of magnetic and self-potential fields, electrotomographic and microseismic sections, and radarogram were built on the research profile. The research has shown different levels of the magnetic field and the SP in the area of volcanic rocks and dikes of gabbro-dolerites occurrence. A significant increase in microseismic noise was observed with an increase in the weathering crust thickness. A local decrease in the SP potential, abnormally high values of specific electrical resistivity and intensive reflections of radio waves from the tunnel top were recorded above the underground water tunnel. Conclusions. Qualitative and quantitative geophysical characteristics were obtained in the area of the old underground water tunnel. The research showed different levels of the magnetic field and spontaneous polarization potentials in the occurrence area of rocks of different composition. A significant increase in microseismic noise was recorded with an increase in the weathering crust thickness. Geophysical signs of the boundaries between geological structures and artificial underground objects are revealed. The exact position and depth of the old underground tunnel of Glubochinsky hydraulic structures was determined.

Comparison of 4 weeks of cupping and Kinesio-taping on clinical and ultrasound outcomes of carpal tunnel syndrome during pregnancy

ObjectiveTo explore effect of cupping and Kinesio-taping techniques on clinical and ultrasound outcomes of carpal tunnel syndrome (CTS) during pregnancy. MethodsThirty pregnant women suffering from CTS were randomly assigned into Kinesio-taping (n = 15) and cupping (n = 15) groups. In Kinesio-taping group, individuals underwent Kinesio-taping for three days, one day with no treatment, and three days with Kinesio-taping, continuing this procedure for four weeks. In cupping group, cupping was moved for 5 min with pressure of 50 mm-Hg on the carpal tunnel area. This procedure continued longitudinally in forearm area for 2 min. The therapeutic intervention of cupping group continued with eight sessions, two days a week for 4 weeks. Ultrasound outcomes including median nerve cross-sectional area through ultrasonography, and clinical outcomes including pain through visual analog scale and severity of symptoms and functional status through Boston questionnaire were measured in both groups before and after therapeutic program. ResultsIn both groups, a significant reduction was observed in all variables after treatment compared to pre-treatment (P < 0.001). In inter-group comparison, a significant improvement was found in outcomes of Boston questionnaire and ultrasound results about median nerve cross-sectional area at pisiform and hook of hamate in cupping group compared to Kinesio-taping at end of four weeks (P < 0.001). ConclusionBoth cupping and Kinesio-taping improved clinical and ultrasound outcomes of CTS. However, efficacy of cupping compared to Kinesio-taping was better in improvement of median nerve cross-sectional area at hamate hook and pisiform levels, symptoms severity scale, and functional status scale, which makes the results clinically more applicable.

Median Nerve Recovery and Morphological Change on MRI at 24 Months after Open Carpal Tunnel Release.

Background: This study aimed to investigate the relationship between postoperative clinical results and long-term morphological changes in patients with carpal tunnel syndrome (CTS) as observed on magnetic resonance imaging (MRI) before and after open carpal tunnel release (OCTR). Methods: We retrospectively analysed data for 28 hands that had undergone OCTR with at least 24 months of follow-up data. Two-point discrimination (2PD) test results were examined for the first three fingers, as were the distal motor latency (DML) and sensory conduction velocity (SCV) of the median nerve. We also calculated the cross-sectional area (CSA) of the carpal tunnel and the distance from the median nerve to the volar carpal bone at the hamate and the pisiform levels using MRI images. Variables were compared before and 24 months after OCTR. Results: Significant improvements in all variables were observed, including average 2PD scores (Finger I: 13.1 ± 6.2 vs. 7.7 ± 4.3, p < 0.01, Finger II: 11.9 ± 6.6 vs. 7.0 ± 3.5, p < 0.01, Finger III: 13.6 ± 6.1 vs. 7.8 ± 4.5, p < 0.01), average DML (8.3 ± 3.3 vs. 4.3 ± 0.6 m/s, p < 0.01), average SCV (30.8 ± 11.0 vs. 41.3 ± 5.3 m/s, p < 0.01), CSA of the carpal tunnel (hamate level: 194.9 ± 30.6 vs. 254.2 ± 47.6 mm2, p < 0.01, pisiform level: 244.2 ± 46.5 vs. 274.7 ± 75.1 mm2, p = 0.01) and the distance between the median nerve and volar carpal bone (hamate level: 8.7 ± 1.4 vs. 11.2 ± 1.6 mm, p < 0.01, pisiform level: 11.8 ± 1.7 vs. 13.8 ± 2.5 mm, p < 0.01). Conclusions: Our results demonstrate that OCTR is successful in achieving long-term decompression and recovery of the median nerve in patients with CTS. Level of Evidence: Level III (Therapeutic).

Carpal Tunnel Anthropometrics Using Acrylic Casts: A Cadaveric Study With Implications for Carpal Tunnel Release.

Abundant literature exists on the morphology of the carpal tunnel. Despite this, the shape of the carpal tunnel has been reported erratically, and most studies did not attempt to correlate findings with measurements taken from cadavers. The objective of this study was to perform a morphological analysis, determine the shape and mean dimensions of the carpal tunnel, determine the level of the narrowest area of the tunnel, and establish a set of values capable of serving as a reference for carpal tunnel release. The carpal tunnels of 20 fresh cadaveric hands were dissected, and acrylic casts were created and measured using industrial computed tomography. Of the 20 casts, 19 were shaped like elliptic cylinders, with little variation in their measurements along the length. The location of the narrowest section of the carpal tunnel is very different among casts, and the length of the roof of the carpal tunnel ranged from 21.26 to 29.86 mm. The most common shape of the carpal tunnel is an elliptic cylinder. Because of the unpredictability of the location of the narrowest area of the carpal tunnel, carpal tunnel release must continue through all extension of its roof. We advise that the release should rarely be extended distally more than 30 mm from the distal palmar wrist crease, which corresponds, in most cases, to the middle of the pisiform.

Highway Tunnel Fire Traffic Control Plan

Tunnel fire accidents occur from time to time, due to its special structure, will cause huge losses, this paper by studying the division of tunnel fire, put forward the principles and specific measures of traffic control, and carry out zoning control of tunnel fire traffic, and prepare a plan for the traffic control of the affected area and the fire tunnel area.

Quantitative evaluation of attraction intensity of highway landscape visual elements based on dynamic perception

In order to quantify the aesthetic attraction of visual elements of highway landscape space, the concept of visual attraction intensity of highway landscape space is proposed, and the factors and indicators of visual attraction elements are clarified. Based on the perspective of human factors, taking passengers as the main attraction, taking 30 landscape elements from three typical highway landscape scenes, namely mountain highway landscape, plain highway landscape and elevated highway landscape, as the research object. The real-time evaluation and data processing system of subjective landscape preference has been independently developed, and combined with the processing and analysis of human-machine-environment synchronous quantitative analysis technology and in-depth learning, a “subjective+objective” quantitative evaluation model of highway landscape visual element attraction intensity based on dynamic perception has been constructed, revealing the quantitative relationship between highway landscape visual attraction elements and attraction intensity, The quantitative method and action law of the attraction intensity of highway landscape and the dynamic aesthetic perception of the attraction subject is clarified. It is found that the change of highway planning alignment, high green view rate and low enclosure have positive effects on the subjective preference score of the landscape (0.690), and there is a significant positive correlation between green view rate and enclosure; the richer the landscape elements such as mountains, trees and water bodies, the stronger the visual attraction, but the complexity of the landscape elements increases the cognitive load of the area of interest. Among the physiological indicators, there are significant correlations between EEG and ECG (0.790), EDA and ECG (0.632), and subjective preference and passengers' eye-movement behavior and EDA; as well as the change pattern of attraction intensity based on the dynamic perception of tunnel area. The results show that the attraction intensity of visual elements of highway landscape space based on dynamic perception is consistent with human aesthetic preference, visual perception and physiological response, which verifies the scientificity, appropriateness and accuracy of eye-movement analysis method and physiological analysis method for quantitative evaluation of aesthetic preference of highway landscape.

Lane Changing in a Vehicle-to-Everything Environment: Research on a Vehicle Lane-Changing Model in the Tunnel Area by Considering the Influence of Brightness and Noise Under a Vehicle-to-Everything Environment

As there are many factors affecting vehicle lane changes in a tunnel, which leads to the unstable state of vehicles during lane changes and an increase of collision events, a new vehicle lane-changing model is proposed by considering the influence of typical factors such as noise and brightness in a tunnel under a vehicle-to-everything (V2X) environment. First, V2X-based technology enables real-time access to a target vehicle surrounding information characteristics in a tunnel, establishing a lane-changing decision model to quantify the willingness of vehicles to change lanes. Second, considering safety as a prerequisite for a lane change, establishing a vehicle safety lane-change-distance model and a minimum safe-distance model was introduced for comparison to evaluate the safety of lane changing. On this basis, considering the noise and brightness effects of a tunnel, the relationship between brightness, noise, and response time of human-driven vehicles, hybrid driving vehicles, and autonomous vehicles is quantitatively analyzed, and then a new vehicle lane-changing model in a tunnel is established. The results of the research show that brightness in a tunnel has a more significant effect on the driver than noise. At the same time, autonomous driving, as well as hybrid driving, has better stability and comfort with less change in velocity, acceleration, and other states during lane changing in a tunnel compared to manned driving, which proves the reasonableness of the model and helps to provide a model basis for research of real vehicle lane changing under a V2X environment.

Injectable FHE+BP composites hydrogel with enhanced regenerative capacity of tendon-bone interface for anterior cruciate ligament reconstruction.

Features of black phosphorous (BP) nano sheets such as enhancing mineralization and reducing cytotoxicity in bone regeneration field have been reported. Thermo-responsive FHE hydrogel (mainly composed of oxidized hyaluronic acid (OHA), poly-ε-L-lysine (ε-EPL) and F127) also showed a desired outcome in skin regeneration due to its stability and antibacterial benefits. This study investigated the application of BP-FHE hydrogel in anterior cruciate ligament reconstruction (ACLR) both in in vitro and in vivo, and addressed its effects on tendon and bone healing. This BP-FHE hydrogel is expected to bring the benefits of both components (thermo-sensitivity, induced osteogenesis and easy delivery) to optimize the clinical application of ACLR and enhance the recovery. Our in vitro results confirmed the potential role of BP-FHE via significantly increased rBMSC attachment, proliferation and osteogenic differentiation with ARS and PCR analysis. Moreover, In vivo results indicated that BP-FHE hydrogels can successfully optimize the recovery of ACLR through enhancing osteogenesis and improving the integration of tendon and bone interface. Further results of Biomechanical testing and Micro-CT analysis [bone tunnel area (mm2) and bone volume/total volume (%)] demonstrated that BP can indeed accelerate bone ingrowth. Additionally, histological staining (H&E, Masson and Safranin O/fast green) and immunohistochemical analysis (COL I, COL III and BMP-2) strongly supported the ability of BP to promote tendon-bone healing after ACLR in murine animal models.

Research on evolution characteristics of multi-information and stability of goaf under deep tunnel

In order to ensure the safety of construction and operation of the tunnel near the goaf. Based on dynamic numerical analysis, three-dimensional finite difference numerical simulation software was developed by FISH programming. Then, on basis of the construction of practical engineering, the safety distance and energy evolution mechanism in an underlying mining goaf area of deep tunnel are studied. The results show that according to the different safe distance in an underlying mining goaf area of deep tunnel, the tunnel structure is divided into danger zone, influence zone and safe zone. The relationship between the cumulative horizontal energy and stress ratio can be divided into three stages: acceleration, average stability and deceleration. The energy evolution of the three stages can also better reflect the damage and failure mechanism inside the surrounding rock mass. The measured field curve shows that when the safety distance is 12 m, the goaf has limited influence on the stability of the tunnel, and the construction in an underlying mining goaf area of deep tunnel is stable on the whole and meets the safety requirements. The best safe distance between the tunnel and goaf is about one time of the tunnel span.

Impact study of beam losses in TRIUMF’s BL4N proton cave and ARIEL tunnel

As part of the ARIEL project, currently under construction at TRIUMF, a new proton beam line will be installed to transport up to 100 µA of nominal beam energy 480 MeV protons from the main cyclotron extraction port to an isotope separator on-line (ISOL) proton target station. This new beam line, approximately 80 m long, designated beam line 4-North (BL4N), will connect the cyclotron to the ARIEL facility via a tunnel. The proton beam line is designed for beam losses lower than 1 nAm−1 and will feature a collimator to remove the beam halo produced by large-angle scattering in the cyclotron extraction foil.The tunnel will be shared with an electron beam line with its own specific requirements for beam loss mitigation and machine protection, leading to another ISOL electron target station. The electron beam is generated by an e-linac with capacity for 500 kW beam power operation, but is ultimately expected to operate at 100 kW with losses not exceeding 20 nAm−1. After an initial stage of operation at 25 MeV the beam energy will be upgraded to 50 MeV.In this work, the effect of the beam losses, both chronic and catastrophic, in the tunnel and adjacent areas were studied. The FLUKA particle transport and interaction code was employed to estimate the impact of the combined proton and electron beam losses to the shielding, including as well the reflection of radiation from the target stations into the tunnel during ARIEL operation. This analysis resulted into a better assessment of the damage to equipment in the tunnel and the impact on maintenance due to activation of elements of the beam line. Maximum credible accidental scenarios were also detailed to validate the shielding configuration and the safety systems location.

Creation of geomechanical block model of Severomuysky Tunnel area in Micromine Origin &amp; Beyond

In 2016 Russian Railways made a decision to reconstruct the upper structure of the track and drainageand-transport adit in Severomuysky Tunnel in order to mitigate the impacts of adverse factors and to increase the tunnel capacity. As a rule, such work goes with the creation of a 3D model of subsoil in the area of reconstruction. The area of Severomuysky Tunnel features difficult geological and geotectonic conditions. The seismically active zones, subvertical tectonic delamination of granitoid rock mass in the Baikal Mega Dome, as well as the thermal and cold groundwater complicate operation and require special control activities to be undertaken. Creation of the geomechanical model is discussed, the modeling stages are described, the source data of the modeling are given, and the calculation procedure to find geomechanical determinants for the modeling is delineated. The modeling is performed in geological and mining information system Micromine Origin &amp; Beyond. Visualization of distribution of quantitative data on rock mass quality and real-time updating of the model when new geomechanical observations arrive allow enhancing quality of project solutions, including designs of tunnel lining and new underground openings. With the block model at hand, it is possible to identify hazardous areas in rock mass and to predict rock mass damages in three and in two dimensions. The geological and mining information systems are usable both in solid mineral mining and in construction / reconstruction of various-purpose underground structures. At the comparatively low labor cost of modeling, specialists gain an offing to improve essentially the computational accuracy and to minimize the risks associated with construction and operation of objects in difficult geotechnical conditions.