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In this field trial, a new monitoring technique using distributed strain sensing known as Brillouin optical time-domain reflectometry (BOTDR) was introduced to monitor the behavior of bolted-concrete linings of a recently completed tunnel when a second bored tunnel was constructed side by side at a distance less than one tunnel diameter apart. This was done by measuring circumferential strains in 12 rings using optical fiber that was installed using the point-fixing method. The strain distributions around the circumference of the rings show a generally similar profile. Maximum compressive strains measured below the tunnel springline nearest to the excavated tunnel were larger than the maximum tensile strains measured at the tunnel crown, distorting the circular tunnel into an oval/ellipsoid that was about symmetrical to the horizontal axis. Several methods were introduced to compare strain measurements made by BOTDR and diameter changes recorded by tape extensometer. This involves the use of a symmetrical tunnel distortion model and the basic differential equation for a circular arch. The calculated results showed some degree of similarity between the two methods. The analysis highlighted the importance of measuring the axial strain in the tunnel ring and subtracting the axial strain component to calculate the actual deflection of the lining as a result of bending.

This paper examines the effect that tunnel size, depth and volume loss have on greenfield soil displacements above tunnels in sandy ground. The results of a series of plane-strain centrifuge tests performed on tunnels in a dry silica sand are examined. The cover-to-diameter ratio, C/D, of the tunnels ranged from 1·3 to 4·4. Features of greenfield settlement trough shape, both surface and subsurface, are illustrated by examining soil displacement data obtained using an image-based deformation measurement technique. The effects of tunnel size, depth and volume loss are demonstrated, and the suitability of typical fitting curves is discussed. The complex volumetric behaviour of drained soil is illustrated by comparing tunnel volume loss with the volume loss experienced by the soil. A set of equations is developed that provide a method of evaluating the change of settlement trough shape with tunnel size, depth and volume loss.

Excavation of a tunnel induces small movements at the surface of the ground above. Those movements are often estimated by empirical methods. This paper presents a simple derivation of formulas for elastic ground, based on the reciprocal theorem. It confirms that the effect of removal of the weight of the soil in the tunnel is not negligible.

The paper examines the problem of tunneling beneath buried pipelines and the relationship between soil strains and pipeline bending behavior. Data are presented from centrifuge tests in which tunnel volume loss was induced in sand beneath pipelines of varying stiffness properties. The model tunnel and pipelines were all placed at a Perspex wall of the centrifuge strong box such that image-based deformation analyses could be performed. The method provided detailed data of subsurface soil and pipe displacements and illustrated the soil-pipe interaction mechanisms that occurred during tunnel volume loss, including the formation of a gap beneath the pipes. The relationship between tunnel volume loss, soil strain, and pipe bending behavior is illustrated. Experimental results of pipe bending moments are compared against predictions: (1) assuming the pipe simply follows greenfield displacements; (2) using an elastic continuum solution; and (3) using a new method in which an "out-of-plane" shear argument, due to soil-pipe interaction, is introduced into the elastic continuum solution. It is shown that the new method gives the best prediction of experimental pipe bending moments.

A novel technique of distributed strain sensing is introduced using Brillouin optical time-domain reflectometry to examine the performance of an old masonry tunnel during the construction of a new tunnel beneath it in London. Optical fibres attached along the intrados of the tunnel lining at five circumferential sections recorded the relative strains of tunnel deformation between the fixing points as well as detecting localised strain such as cracking in the masonry. The results indicated where cracking might have occurred and were confirmed with visual inspection. Measurements were compared with the data obtained by surveying using total station units and the results show close agreement between the two systems. Flexural behaviour along the longitudinal section of the tunnel was also examined by measuring strain along the springlines and crown.

Within the framework aiming at assessing the potential risk of the use of wood ash amended composts to tropical acid soils, a greenhouse experiment was conducted with two acid soils (Oxisol and Ultisol) collected from Cameroon and amended with three types of compost 3:1 (w/w) prepared with 0, 8 and 16% wood ash prior to composting, respectively. They were planted with soybean ( Glycine max L.) for 100 d. Addition of organic waste composts increased soil pH, SOM, WHC, EC, total C and N. Concentrations of exchangeable Al and NH 4 + –N decreased while those of NO 3 − –N and phosphorous increased. The exchangeable cation (Ca, Mg, Na and K) and micronutrient (Zn and Cu) concentrations increased while concentrations of Fe and Mn decreased. The C/N ratio of treated soils ranged from 12 to 14. Soil pH, concentrations of Fe and Mn were higher; EC and nitrate concentration were lower under ash compost amendment. Eight percent ash amendment to compost yielded best results in many aspects. Concentration of exchangeable Al was most decreased in soils treated with compost without ash. Plant biomass production was not significantly enhanced by compost amendment. This lack of an effect may be attributed to a soil pH (> 7.7) beyond the optimum for soybean (6.2). Summarising the results, composts with ash addition could serve the purpose of ameliorating acid tropical soils, albeit the optimal amendment rates still need to be addressed in future research.

New developments in both the theory and the practice of tunnelling are covered in the lecture. The important relationship between tunnelling and geotechnics is highlighted, and recent advances in research and practice are described, drawing on model studies, theoretical developments and field measurements from case histories from around the world. Simplified plasticity models are presented that can be used by designers to assess ground movements and tunnel lining loads in complex ground conditions. The important role of pilot tunnels and in situ measurements to validate such models, drawing on a case history from Bolu, Turkey, and on other tunnelling projects, is described. Recent technical advances in earth pressure balance tunnelling are considered, illustrated by measurements from the Channel Tunnel Rail Link project, with emphasis on key factors influencing volume loss, such as face pressure, soil conditioning and effective screw conveyor operation. A recent case history in Bologna is described, in which the innovative use of directional drilling to install curved grout tubes was employed for a compensation grouting project in granular soils. Time-dependent ground movements and tunnel lining distortions occurring after tunnelling are discussed, their magnitude depending on the relative permeability of the tunnel lining and soil, the degree of anisotropy of the soil permeability, and the initial pore pressure prior to tunnelling. The effects of tunnelling-induced settlements on pipelines are considered, drawing on centrifuge tests and analytical solutions, and a new design approach is presented, taking into account the reduction of soil stiffness with increasing shear strain as a result of tunnel volume loss. The lecture concludes with a description of a distributed strain sensing technique using fibre optic technology, based on Brillouin optical time domain reflectometry (BOTDR), and its innovative application to field monitoring of a masonry tunnel subjected to new tunnel construction beneath it.

The progressive response of two–three storey masonry buildings to bored tunnelling on the Jubilee Line Extension in London is investigated in order to determine the effect of building stiffness on tunnelling-induced ground movement. The masonry buildings, at Moodkee Street and Keetons Estate, were affected by tunnelling with earth pressure balance machines on Contract 105 of the Jubilee Line Extension. Bending deformations and axial strain induced in these structures are compared to greenfield ground deformations and strain in order to infer the effect of building stiffness. The modifying influence of the stiffness of these buildings on ground movement is interpreted using the Potts and Addenbrooke [Potts D.M., Addenbrooke, T.I., 1997. A structure’s influence on tunnelling induced ground movements. Proc. Inst. Civ. Eng. Geotech. Eng. 125 (2), 109–125] method, which is based on a series of finite element analyses. The inferred building stiffness that can be used for design purposes with the Potts and Addenbrooke method is compared to an estimation for a Class A [Lambe, T.W., 1973. Predictions in geotechnical engineering. Geotechnique 23 (2), 149–202] prediction exercise by Mair and Taylor [Mair, R.J., Taylor, R.N., 2001. Settlement predictions for Neptune, Murdoch and Clegg Houses and adjacent masonry walls. Building response to tunnelling – case studies from construction of the Jubilee Line Extension, London. In: Burland, J.B., Standing, J.R., Jardine, F.M. (Eds.), Projects and Methods, vol. 1. CIRIA SP200, pp. 217–228 (CIRIA and Thomas Telford, 2001). ISBN: 0 7277 30177] using the same method. As a result an alternative approach is proposed for estimating the relative bending stiffness of masonry structures for future use with the Potts and Addenbrooke method when making simple predictions.

The problem of tunneling effects on existing jointed pipelines is studied using the boundary integral method. Normalized solutions to evaluate the maximum bending moments and rotations are presented. They depend on tunnel-induced ground settlements at pipeline level, relative soil–pipe stiffness, relative pipe-joint stiffness, and the location of the joints in relation to the tunnel centerline. A jointed pipeline generally experiences smaller bending moments than a continuous one owing to the joint rotation. The solutions indicate that there are certain cases where hinged systems result in greater bending moments than continuous ones. However, these cases rarely occur in reality.

Recently, the International Parkinson and Movement Disorder Society has defined research criteria for prodromal Parkinson's disease (PD), but to date their predictive value has not yet been tested in population-based cohorts.We retrospectively applied these criteria to the longitudinal Bruneck Study cohort aged 55-94 years using recorded data on all included risk and prodromal markers that are quick and easily assessable.After excluding participants with idiopathic PD or secondary parkinsonism, prevalence of probable prodromal PD in the remaining 539 participants was 2.2% (95% confidence interval, 1.2%-3.9%). Of 488 participants followed up over 5 years, 11 developed incident PD. Sensitivity of "probable prodromal PD" status for incident PD was 54.6% (95% confidence interval, 28.0%-78.8%), specificity was 99.2% (97.8%-99.8%), positive predictive value was 60.0% (31.2%-83.3%), and negative predictive value was 99.0% (97.5%-99.6%).Our findings suggest that the new research criteria for prodromal PD are a promising tool to identify cases of incident PD over 5 years, arguing for their usefulness in defining target populations for disease-prevention trials. © 2016 International Parkinson and Movement Disorder Society.

Diaphragm walls are used to support the sides of deep excavations, and they are often installed close to existing buildings. Construction of these cast-in-place permanent retaining structures can result in substantial soil deformations and potential damage to adjacent structures. A better understanding of this soil–structure interaction problem would greatly benefit safe and economic design. There is particular uncertainty about the interaction and response of piled foundations to diaphragm wall construction, particularly where there could be trench instability at depth. A series of small-scale model tests has been conducted using the 8 m diameter geotechnical centrifuge at Cambridge University to study the installation effects of diaphragm walls on a single adjacent pile in dense fine sand. An instrumented model pile was installed and loaded at various offsets from a slurry-filled model trench. Two trench lengths were investigated. The tests have provided a detailed insight into the movements of the pile and the progressive redistribution of loads along the pile. A generalised mechanism for the pile–trench interaction is also proposed. The main factors affecting the severity of pile response are slurry level (trench pressure), pile offset distance (α) and trench length (L). The experiments showed that the risk of system instability reduced significantly with x/L values above 1·15.

Solutions for the problem of tunneling effects on existing pipelines are given. The solution utilizes a boundary integral formulation for describing the elastic continuum, in conjunction with a limiting force to consider relative pullout failure. The solution requires estimation of soil and pipe elastic properties, relative pipe-soil uplift capacity, and the green field soil settlement profile given in the current paper as a modified Gaussian curve. Normalized graphs for the solution are given as a function of these input parameters. The solution method is compared and evaluated against a limited number of finite-element analysis.

This paper presents an experimental study of the effects of soil loading on large-diameter, close-fitting, non-bonded, flexible sewer liners as typified by ‘cured-in-place pipes’ (CIPP). CIPP is the process whereby a polymeric pipe lining is cast directly against the wall of a deteriorating sewer pipe. The transfer of soil loading to CIPP liners is strongly influenced by the interaction between the existing host pipe and the surrounding soil. In adjusting to deterioration events of the host pipe and possible void formation in the soil, the existing pipe-soil structure deforms and interacts with the liner inside it. By monitoring deformations of the liner and host structure the magnitude of load transfer can be inferred. The paper describes 1/30th scale physical models tested in dry sand under 30g of centrifugal acceleration. The models included: (a) a host pipe with two simulated modes of deterioration; (b) an instrumented close-fitting, non-bonded, flexible liner; (c) voids in the soil; and (d) moving, heavy traffic loading. The tests showed that, even under extreme loading conditions, the deformations of the liner are relatively small (2–3% of diameter), implying that the presence of a thin, flexible non-bonded and close-fitting liner has an important stiffening effect on the response of the deteriorating host pipe. The important influence of void position in the surrounding soil was also demonstrated.

Following a tunnel excavation in low-permeability soil, it is commonly observed that the ground surface continues to settle and ground loading on the tunnel lining changes, as the pore pressures in the ground approach a new equilibrium condition. The monitored ground response following the tunnelling under St James's Park, London, shows that the mechanism of subsurface deformation is composed of three different zones: swelling, consolidation and rigid body movement. The swelling took place in a confined zone above the tunnel crown, extending vertically to approximately 5 m above it. On the sides of the tunnel, the consolidation of the soil occurred in the zone primarily within the tunnel horizon, from the shoulder to just beneath the invert, and extending laterally to a large offset from the tunnel centreline. Above these swelling and consolidation zones the soil moved downward as a rigid body. In this study, soil–fluid coupled three-dimensional finite element analyses were performed to simulate the mechanism of long-term ground response monitored at St James's Park. An advanced critical state soil model, which can simulate the behaviour of London Clay in both drained and undrained conditions, was adopted for the analyses. The analysis results are discussed and compared with the field monitoring data. It is found that the observed mechanism of long-term subsurface ground and tunnel lining response at St James's Park can be simulated accurately only when stiffness anisotropy, the variation of permeability between different units within the London Clay and non-uniform drainage conditions for the tunnel lining are considered. This has important implications for future prediction of the long-term behaviour of tunnels in clays.

This paper describes the nature of ground movement observed during construction of the Jubilee Line Extension at St James's Park and beneath Elizabeth House for different stages of tunnelling in London Clay, using open-face shield construction and sprayed concrete linings respectively. Volume loss is defined as the volume of ground loss as a proportion of the final tunnel volume and is measured in the plane of the tunnel. Volume losses corresponding to different phases of tunnelling at St James's Park and beneath Elizabeth House are identified in the paper. A companion paper presents a new approach to estimating volume losses for each phase of open-face tunnelling in London Clay.

A modification to the load factor approach to estimating undrained volume loss for open-face tunnelling in London Clay is proposed. The modified approach is based on the nature of ground movement observed during construction of the Jubilee Line Extension at St James's Park and Elizabeth House for different stages of open-face shield tunnel construction and tunnelling using sprayed concrete linings, described in a companion paper. The new approach is shown to provide good estimates of the volume loss observed for open-face shield tunnelling in London Clay at Green Park and Regents Park.

Control of the excavation process of an earth pressure balance (EPB) tunnelling machine depends on control of the soil flow through the screw conveyor. An instrumented 1:10 scale model screw conveyor was designed and commissioned, and tests were performed with consolidated kaolin and compacted London Clay and Lambeth Group samples pre-conditioned with soil conditioning agents commonly used in EPB tunnelling machines. During steady-state operation, the measured shear stress acting on the conveyor casing was found to be constant along the conveyor, leading to a linear total pressure gradient. The casing shear stress was approximately equal to the un-drained shear strength of the soil, and the screw torque increased linearly with the casing shear stress. Effects of varying sample strengths, screw speeds, screw geometry and the discharge outlet restriction on the total pressure gradient, casing shear stress, and screw torque are illustrated by the test results. The tests provide new insight into the behaviour of soil flow through screw conveyors.

Brain imaging studies as well as neuropsychological case studies suggest an important role for basal ganglia in arithmetic processing. Aim of this study was to assess possible numerical deficits in PD and functional relations between numerical and other cognitive deficits. Fifteen non-demented patients with early PD (stable responders treated by l-dopa) were compared to 28 healthy age and education matched controls. Both groups underwent a neuropsychological assessment focussing on numerical abilities (quantity processing, arithmetic fact retrieval, complex mental and written calculation, transcoding, arithmetic set-shifting, calculation span), working memory and executive functions. Patients with PD showed deficits in complex mental calculation and calculation span tasks. Results of this study suggest that impairments in working memory as well as in executive functions, such as inhibition of interference, lead to secondary deficits in numerical processing. The study contributes to better understanding the specific cognitive deficits in early PD and the neurocognitive architecture of arithmetic processing.

Summary Chorea is one of the major types of involuntary movement disorders originating from dysfunctional neuronal networks interconnecting the basal ganglia and frontal cortical motor areas. The syndrome is characterised by a continuous flow of random, brief, involuntary muscle contractions and can result from a wide variety of causes. Diagnostic work-up can be straightforward in patients with a positive family history of Huntington's disease or acute-onset hemichorea in patients with lacunar stroke, but it can be a challenging and complex task in rare autoimmune or genetic choreas. Principles of management focus on establishing an aetiological classification and, if possible, removal of the cause. Preventive strategies may be possible in Huntington's disease where genetic counselling plays a major part. In this review we summarise the current understanding of the neuroanatomy and pathophysiology of chorea, its major aetiological classes, and principles of diagnostic work-up and management.

Recent advances in strain measurement using optical fibres provide new opportunities for monitoring the performance of piles. Brillouin optical time-domain reflectometry (BOTDR) is an innovative technique that allows measurement of full strain profiles using standard optical fibres. Distributed optical fibre strain sensors were installed at two sites, and the details of the installation methods are presented. A theoretical analysis that compares pile behaviour evaluated from localised strain measurement at discrete locations and from distributed strain measurements is conducted for the case of a vertically loaded pile in layered soil. Two problems are considered: a load test aiming to establish the load transfer function, and changes in pile–soil interface stress due to nearby tunnelling. Advantages of such a distributed reading for monitoring the performance of pile foundations in layered soils are demonstrated from the results of both cases. Cost analysis results show that the BOTDR measurement is a cost-effective pile monitoring method compared with discrete strain measurement methods such as vibrating-wire strain gauges and fibre Bragg gratings.

Huntington's disease (HD) is an autosomal dominant progressive neurodegenerative disorder that results from an expanded trinucleotide (CAG) repeat on the huntingtin gene. Neurodegeneration in HD affects most prominently the basal ganglia. Therefore, diffusivity was obtained in the basal ganglia and thalamus of 29 patients with early HD and 27 healthy volunteers by means of the trace of the diffusion tensor (Trace(D)). Putaminal, caudate, pallidal, and thalamic Trace(D) values were increased in patients with HD compared with controls. Increased diffusivity in the putamen and caudate nucleus correlated with global functional impairment, CAG repeat length, as well as bicaudate ratio. Diffusion-weighted imaging appears to be a promising surrogate marker for disease severity in HD. Sensitivity to change remains to be established longitudinally.

A method is presented for estimating the maximum bending moment for continuous (or rigidly jointed) pipelines affected by tunnel-induced ground movement. The estimation can be made based on the knowledge of tunnel and pipeline geometries, the stiffness of soil and pipeline, and tunnel-induced ground deformation at the pipeline level. The method takes account of soil nonlinearity by an equivalent linear approach, in which the stiffness of the soil is evaluated based on an average deviatoric strain developed along the pipeline. The approach is conservative and promises that the bending moment is not underestimated. The validity of the method as an upper bound approximation is evaluated against centrifuge test results.

An elastic continuum solution and a Winkler solution of the problem of tunnelling effects on existing pipelines are given. A comparison is made between an elastic continuum solution and a closed-form Winkler solution with Vesic subgrade modulus. Although applying the Vesic expression results in the same moments and displacements under external loading in a Winkler system and the elastic continuum, it is found that its use is not necessarily adequate for the problem of tunnelling effects on pipelines and may not be conservative owing to possible underestimation of bending moments. An alternative expression for the subgrade modulus is provided, resulting in similar maximum bending moments in the Winkler and elastic continuum systems.

This paper reports the findings of a field study of the ground conditions around an old tunnel in London Clay at a greenfield site in Kennington, South London. Ground conditions were identified from a borehole investigation incorporating a programme of in situ pore water pressure monitoring, geotechnical testing and sampling. Additionally, laboratory classification of the samples and a suite of high-quality triaxial tests were carried out. The results of this investigation are presented and discussed in conjunction with published London Clay data. The presence of a tunnel beneath the site allowed the investigation of its influence on the local soil and groundwater conditions.

Purpose To evaluate the technical feasibility of the implantation of the monorail RX Herculink system into the renal arteries without pre-dilatation. Materials and methods Forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink stent. The mean grade of the stenosis was 83.8 %, the mean length 7.5 mm. The stenoses were ostial in 38 cases and in immediate proximity to the ostium in 6 cases. The mean follow-up-period was 57 weeks (24 - 176 weeks). Results In 42 cases, the implantation was successful without pre-dilatation. In 2 cases, pre-dilatation was carried out. In none of the cases, detachment of the stent from the balloon was observed. In one stenosis with a length of 17 mm, implantation of two stents was performed. In 9 cases, post-dilatation with a larger balloon or higher balloon pressure was necessary. Residual stenoses exceeding 30 % were not observed. Two patients developed local bleeding at the puncture site. During the follow-up, restenoses were observed in 5 stents after 26 to 126 weeks, which necessitated a second intervention in 3 cases (PTA in 2 cases, re-stenting in 1 case). The primary patency rate after 6 and 12 months was 0.92 +/- 0.056 according to Kaplan-Meier, the secondary patency rate after 6 and 12 months was 1.0 +/- 0.0. Conclusion Implantation of the RX Herculink stent system into the renal arteries without pre-dilatation is technically feasible and safe. Even without pre-dilatation, the stent-system can be advanced through the stenosis without detachment. The complication rate is low. Our clinical results are comparable to previous studies.

A centrifuge model study was carried out to investigate the effects of tunnelling on nearby single piles in dense dry sand. This paper presents a description of the centrifuge model and the test procedures followed. The surface settlement profiles recorded during tunnelling-induced volume loss are discussed, as well as the settlement of piles installed at various distances from the tunnel. A zone was identified around the tunnel in which a potential for large settlement exists. Changes in the load distribution on individual piles at various locations during increasing volume loss are presented.

Objective— To compare single versus double semitubular plate fixation for scapular body fractures. Study Design— Ex vivo mechanical study. Sample Population— Eighteen paired cadaveric canine scapulae. Methods— Transverse scapular body osteotomies were created in the distal third of 18 pairs of scapulae. One scapula of each pair was repaired with a single plate, whereas the contralateral scapula was repaired with 2 plates. Initial strength and stiffness of the constructs were measured in 10 pairs of scapulae. Eight pairs of scapulae underwent cyclic loading and then were subjected to failure testing. Results— Double-plate fixation was significantly stronger (3,899 ± 632 N) but not stiffer (614 ± 130 N/mm) than the single-plate fixation (3,238 ± 935 N and 537 ± 202 N/mm, respectively). Cyclic loading variables were not significantly different between the 2 methods of fixation. After cyclic loading, double-plate fixation was significantly stronger (2,916 ± 618 N) than single-plate fixation (2,347 ± 495 N). There was no significant difference (P= .11) in stiffness between double- versus single-plate fixations: 734 ± 247 N/mm and 595 ± 139 N/mm, respectively. Conclusions— Double-plate fixation was generally stronger and stiffer than single-plate fixation. Because all constructs failed at loads that greatly exceeded those estimated to occur clinically, any difference between the 2 methods of fixation probably is not clinically relevant. Clinical Relevance— Single-plate fixation may be of sufficient strength for fixation of scapular body fractures.

Many claims have been made in recent years regarding the utility of plasma B-type natriuretic peptide (BNP) concentration measurements in the diagnosis, risk stratification and monitoring of patients with heart failure. This paper summarizes the current evidence and provides guidance for practising clinicians. Overall, plasma BNP testing appears to be of most value in the diagnostic arena, where it is likely to improve the performance of non-specialist physicians in diagnosing heart failure. In clinical practice, BNP testing is best used as a 'rule out' test for suspected cases of new heart failure in breathless patients presenting to either the outpatient or emergency care settings; it is not a replacement for echocardiography and full cardiological assessment, which will be required for patients with an elevated BNP concentration. Although work is ongoing in establishing the 'normal' values of BNP, heart failure appears to be highly unlikely below a plasma concentration of 100 pg/ml. However, as BNP levels rise with age and are affected by gender, comorbidity and drug therapy, the plasma BNP measurement should not be used in isolation from the clinical context.

From the early days of tunnelling, developments in lining technology relied on laboratory testing and analyses of field monitoring data. This approach is still commonly implemented by designers to enhance their knowledge on lining performance and to, ultimately, develop, validate and optimise their assumptions, methods and solutions. Novel structural health monitoring techniques such as distributed fibre-optic strain sensing bring an excellent opportunity to capture global behaviour of concrete segmental lining by embedding fibre-optic strain sensors during the segment cast. Cambridge University, in collaboration with Hochtief (UK) Construction and Crossrail Ltd., has instrumented four rings in the newly constructed Thames tunnel. This has provided a complete set of in situ monitoring data on ring deformations sensed by both conventional and fibre-optic instrumentation. The monitoring regime was purposely designed to capture measurements during the construction process, including tunnelling and cross passage construction. The results will be used in the future to describe the real history of deformations, stresses and forces developed in concrete segmental lining in shallow tunnels excavated in chalk. In this paper, Brillouin Optical Time Domain Reflectometry (BOTDR) and vibrating wire strain gauge (VWSG) strain measurements are compared and discussed to validate the use of the distributed optical fibre sensing technique for concrete segmental linings.

In many cases, new tunnels in highly populated urban cities like London will need to be constructed underneath a dense network of existing tunnels to avoid them. The construction of new tunnels, however, inevitably results in ground deformations, which are transmitted to adjacent existing structures. The response of existing cast iron tunnels to tunnelling-induced deformation is not well understood and practicing engineers are faced with significant uncertainties about their response. The first part of this paper presents a case study in which distributed fibre optic strain sensing (DFOSS) have been deployed in a section at an existing cast iron tunnel in London underneath which a new, much larger tunnel was being constructed. The DFOSS deployment in this case study provided a detailed response for the cast iron tunnel in a holistic manner that is not encountered in practice. In the second part of the paper, one of the latest case studies being conducted at the Cambridge Centre for Smart Infrastructure and Construction (CSIC), associated with the instrumentation and monitoring of cross-passages in sprayed concrete tunnel linings (SCL) is presented and discussed. The DOFSS provided new data and hence new insights into SCL behaviour that was not available before. doi: 10.12783/SHM2015/197

Uneven loading resulting from asymmetrical grout injections near a tunnel poses a risk of damaging tunnel linings. Counter-rotation of lining segments at joints concentrates the increase of lining stress and strain at the joints. The damage of lining joints will be more significant if the joints are not constructed properly. This paper discusses results from four centrifuge tests investigating the behaviour of a segmental lining when subjected to nearby asymmetrical injections. The tests were carried out in dense dry sand. Cavity expansion analytical solutions and finite element analysis are also presented to envisage the transfer of the injection pressure to the tunnel and the pattern of the lining deformation. Both analytical and numerical solutions show reasonable agreement with the observed tunnel lining deformation.

Compensation grouting involves making grout injections at close neighboring locations so as to replace ground loss, due to tunnelling for example. Since the objective of the technology is to match volume changes so as to eliminate subsidence, the tendency of ground to dilate or compress around the injection becomes a very significant consideration. Furthermore, the effects of different sequences of grout injection, and the zoning of injection relative to the tunnel centreline, are of interest when devising grouting schemes. This paper investigates these issues using centrifuge and numerical modelling in dense and loose dry sand. It is found that the profile of surface heave and the tunnel lining deformation is dependent on the relative injection position, as well as injection history. Ground stiffening due to the compaction arising from previous injection permits larger pressures to be developed from a given injection volume. These larger pressures eventually cause upward heaving and lining deformation. In conclusion, the most favourable and unfavourable injection sequence are identified in relationship to the induced centre surface heave and tunnel lining deformation.

Centrifuge modelling was carried out to simulate the effect of compensation grouting on segmental tunnel lining and ground surface movement in dry sand. Two types of injection were investigated, namely strip injection and multi-point simultaneous injection. For strip injection, the investigated parameters are injection depth, injection distance to tunnel crown (separation), and injection width. The surface heave and lining deformation are found to follow the ratios of injection depth/injection width, and separation/injection width, respectively. To predict the ultimate uplift resistance of soil, two failure mechanisms are proposed for dense and loose sand conditions. In addition, a simple grout pressure transfer mechanism is also suggested to clarify the relationship between the maximum lining deformation and the parameters investigated. The multi-point simultaneous injection tests were conducted to investigate the effect of distributing the injection area. It was found that the sparseness of the injection points has brought beneficial effect to the surface heave and to the lining deformation. In all tests, dense sand shows dilation while loose sand undergoes compression as injected volume increases.

This paper describes monitoring results of ground movements due to slurry shield tunnelling on the Docklands Light Railway Lewisham Extension (hereinafter referred to as DLR). The DLR tunnels (twin bored tunnels) run from Island Gardens Station to Greenwich Station in East London, passing under the River Thames, a distance of around 4.2 km. The construction of the tunnels, which were at shallow depth, needed an extensive appraisal of the potential damage induced by ground movements to the overlying and underground structures. Therefore, in order to effectively minimize the ground movements, a slurry shield machine with a diameter of 5.85 m was employed. Careful control of excavation was carried out during shield tunnel construction. As a result, the slurry shield tunnelling method in Woolwich and Reading Beds by well controlled monitoring was successfully conducted, leading to volume losses less than 1.0%. This paper focuses on the ground surface movements, particularly the transverse and longitudinal settlement profiles, and volume losses during shield tunnel construction, in relation to the ground conditions. Based on the monitoring results, combined with previous centrifuge model test results and other field monitoring data, practical methods to appropriately predict ground movements due to shield tunnelling are proposed.

A 64-year-old man suffering from an acute posterior wall myocardial infarction underwent primary percutaneous coronary intervention. After several aspiration attempts, tirofiban infusion and pre- and post-dilatation, a bare-metal stent was successfully implanted in the culprit right coronary artery. While the patient did not show any neurological symptoms before or during the procedure, he exhibited hemiplegia and loss of spontaneous speech. Additional magnetic resonance imaging showed an extensive brain stem infarction. This is the first report of a brain stem infarction as a complication of percutaneous coronary intervention. Electronic supplementary material The online version of this article (doi:10.1007/s12471-015-0717-2) contains supplementary material, which is available to authorized users.

Major cities in the world are experiencing a rapid growth in population while becoming increasingly overcrowded and congested. In recent years, this has created a huge demand for underground infrastructure, which often involves the design of major mass transit tunnel systems; these tunnel systems (underground tunnels and metro stations) are becoming increasingly necessary to construct in very close proximity to existing buildings. The prediction of excavation-induced deformations, therefore, becomes a key issue in the planning and design process for these schemes. However, current design approaches are conservative and often lead to unnecessary concern and expenditure in the design and provision of protective measures. A better understanding of the mechanisms involved in the excavation soil–structure interaction could reduce costs and help avoid potential problems. A series of small-scale model tests was carried out in the geotechnical centrifuge at Cambridge University to investigate the interaction between excavations and model buildings. Excavations (simulated by adopting a novel two-fluid technique) in a “free field” were also undertaken to assess the difference between free-field ground movements and those affected by a stiff model building. A detailed description of the centrifuge models and test procedures is presented in this paper, followed by the presentation of test results that demonstrate the effect of the stiffness of the model building on the excavation-induced displacements.

The aim of this study was to investigate the distribution and the degree of asymmetric putaminal dopamine transporter availability in right-handed patients with Parkinson’s disease and its association with the severity of lateralized motor signs. Asymmetry of motor symptoms was defined by the difference between right- and left-sided scores for lateralized items assessed by the Unified Parkinson’s Disease Rating Scale Motor Score in a series of 68 patients with Parkinson’s disease (disease duration 2.1 ± 1.5 years; Unified Parkinson’s Disease Rating Scale Motor Score 22.7 ± 9). Putaminal dopamine transporter availability was measured with the radioligand [123I]β-carboxymethyoxy-3 -β-(4-iodophenyl) tropane ([123I]β-CIT) and single photon emission computed tomography. We found that in the right-handed Parkinson’s disease cohort, the number of patients who had lower dopamine transporter uptake in the left posterior putamen was significantly greater compared with those with lower uptake in the right posterior putamen (Parkinson’s disease-left group, n = 49; Parkinson’s disease-right group, n = 19; P < 0.001). In addition, one-way analysis of variance revealed significant reductions of mean total putaminal [123I]β-CIT binding of the Parkinson’s disease-right patients compared with Parkinson’s disease-left patients ( P < 0.05).The preponderance of reduced left putaminal dopamine transporter availability strengthens clinical observations of a greater proportion of right-handed patients with Parkinson’s disease with predominantly right-sided motor signs and argues against a randomly distributed asymmetric vulnerability of substantia nigra dopaminergic neurons. The coexistence of a subgroup of right-handed patients with Parkinson’s disease with more severe and predominant ipsilateral putaminal dopamine transporter decline suggests that asymmetry of dopaminergic denervation and motor dysfunction in Parkinson’s disease cannot be fully explained by hemispheric dominance alone, but that other factors must be involved. * Abbreviations : [123I]β-CIT : [123I]-2β-carbomethoxy-3β-(4-iodophenyl)tropane Bmax : maximum receptor concentration BPND : binding potential PD-LEFT : patients with Parkinson’s Disease with lower [123I]β-CIT BPND values in their left putamen PD-RIGHT : patients with Parkinson’s Disease with lower [123I]β-CIT BPND values in their right putamen SPECT : single photon emission computed tomography UPDRS : Unified Parkinson’s Disease Rating Scale VND : radioligand distribution volume of non-displaceable compartment VT : radioligand distribution volume of total ligand uptake in tissue

A new escalator tunnel and associated passageways have been constructed at Waterloo station in London, passing only a few metres beneath two sensitive masonry structures. Compensation grouting was undertaken in the ground between the tunnels and the overlying structures to limit settlements to acceptably small levels. This comprised injections of grout during tunnelling in response to detailed observations of ground and structure movements. The observational method was used in the control of the compensation grouting operations. This was achieved by comparison of field observations with defined limits of acceptable behaviour, and by planned contingencies in the event that these limits were approached. The extensive instrumentation installed to monitor the movements of the ground and the structures during tunnelling is described. Details are given of the performance of the instrumentation, of the measurements made and of the interpretation of the observations required to evaluate the soil-structure interaction behaviour. The specified requirements for compensation grouting and a summary of the grouting operations are presented. Settlements of the structures due to tunnelling were restricted to less than 15 mm. The relatively novel technique of compensation grouting has proved very successful in limiting settlements. Un nouveau tunnel d'escalator et les couloirs associés ont été construits à la gare de Waterloo, à Londres. Ils passent quelques mètres seulement au dessous de deux structures de maçonnerie particulièrement sensibles. Un coulis compensateur a été injecté dans le terrain entre les tunnels et les structures sus-jacentes pour limiter le tassement à des valeurs faibles acceptables. Ceci consiste à injecter du coulis lors du percement du tunnel en fonction d'observations minutieuses de mise en mouvement du terrain ou des structures. La méthode d'observation a été utilisée pour contrôler la mise en place du coulis compensateur. Ceci a été réalisé en comparant les observations de terrain à des limites définies de comportement acceptable, et en parant à l'imprévu au cas où ces limites seraient approchées. On décrit l'instrumentation mise en place pour enregistrer à la fois les mouvements du terrain et ceux des structures. On détaille les performances de cette instrumentation, les mesures réalisées et l'interprétation des observations permettant d'évaluer l'interaction sol-structure. On présente également les conditions requises et le résumé des opérations de mise en place du coulis compensateur. Le tassement des structures dû au tunnel a été inférieur à 15 mm. La technique du coulis compensateur s'est donc révélée efficace pour limiter les tassements.

Resume Un dosage immunoenzymometrique (IEMA) de la troponine I cardiaque (Tnl c) humaine a ete utilise dans deux situations cliniques principales: 1) chez des patients (pts) admis en unites de soins intensifs pour infarctus aigu du myocarde (IAM); 2) chez des pts beneficiant d'une chirurgie de ravascularisation coronaire chez lesquels est recherchee une necrose perioperatoire. Tnl c est detectee chez tous les pts presentant un IAM. La detection est relativement precoce, 4,3±2,4 heures (moyenne ± DS) apres le debut de la douleur. La cinetique observee de Tnl c est parallele a celle de CKMB; la survenue du pic maximum se situe environ 12,2±4,6 heures apres le debut de la douleur chez les pts traites par fibrinolytiques. La disparition plasmatique de Tnl c est observee generalement entre 5 et 9 jours apres le debut de la douleur. Chez 50 pts admis pour IAM, tous traites par fibrinolyse, la sensibilite globale du test est de 92,9% (au seuil 0,1 ng/ml), la specificite de 100%. Tnl c n'est pas detectee dans le plasma de 145 sujets normaux. Tnl c n'est retrouvee chez aucun des six pts avec traumatisme musculaire severe ou rhabdomyolyse. Le dosage de Tnl c a ete utilise egalement pour etablir le diagnostic d'infarctus du myocarde perioperatoire chez des pts beneficiant d'une chirurgie de pontage coronaire. Des valeurs de concentrations de Tnl c au pic

From criminal complaint records all incidents of sexual misbehaviour resulting in charges in three North East Scotland courts during 1981 and 1982 were traced. Of the 80 alleged offenders, 75 were followed up for 10 years using current criminal records. Offending behaviour ranged from obscene telephone calls to rape. Half the offenders made no physical contact with their victims. These “hands-off” offenders were compared with “hands-on” offenders and were found to show a higher prevalence of sexual convictions both before the index offence and in the follow-up period. Those offenders who removed their victims clothes or had sexual intercourse with their victims were found to have the lowest prevalence of sexual reoffending. Degree of intrusiveness was inversely related to sexual recidivism in this sample and there was no evidence of progression over time to more intrusive offending.

One of the obstacles to widespread deployment of phase-resolved partial discharge (PD) diagnostics is the complexity of deploying and operating new monitoring systems. Typically, these rely upon synchronization with the electrical system frequency via a power line connection, introducing cost, inconvenience and risk into the system. For utilities to exploit partial discharge monitoring on a wide scale, a new approach is required that can work asynchronously which, looking forward, can be combined with wireless sensor network technology.