The injection of large volumes of natural gas into geological formations,as is required for underground gas storage,leads to alterations in the effective stress exerted on adjacent faults.This increases the potential ...The injection of large volumes of natural gas into geological formations,as is required for underground gas storage,leads to alterations in the effective stress exerted on adjacent faults.This increases the potential for their reactivation and subsequent earthquake triggering.Most measurements of the frictional properties of rock fractures have been conducted under normal and shear stresses.However,faults in gas storage facilities exist within a true three-dimensional(3D)stress state.A double-direct shear experiment on rock fractures under both lateral and normal stresses was conducted using a true triaxial loading system.It was observed that the friction coefficient increases with increasing lateral stress,but decreases with increasing normal stress.The impact of lateral and normal stresses on the response is primarily mediated through their influence on the initial friction coefficient.This allows for an empirical modification of the rate-state friction model that considers the influence of lateral and normal stresses.The impact of lateral and normal stresses on observed friction coefficients is related to the propensity for the production of wear products on the fracture surfaces.Lateral stresses enhance the shear strength of rock(e.g.Mogi criterion).This reduces asperity breakage and the generation of wear products,and consequently augments the friction coefficient of the surface.Conversely,increased normal stresses inhibit dilatancy on the fracture surface,increasing the breakage of asperities and the concomitant production of wear products that promote rolling deformation.This ultimately reduces the friction coefficient.展开更多
Severe well interference through complex fracture networks(CFNs)can be observed among multi-well pads in low permeability reservoirs.The well interference analysis between multi-fractured horizontal wells(MFHWs)is vit...Severe well interference through complex fracture networks(CFNs)can be observed among multi-well pads in low permeability reservoirs.The well interference analysis between multi-fractured horizontal wells(MFHWs)is vitally important for reservoir effective development.Well interference has been historically investigated by pressure transient analysis,while it has shown that rate transient analysis has great potential in well interference diagnosis.However,the impact of complex fracture networks(CFNs)on rate transient behavior of parent well and child well in unconventional reservoirs is still not clear.To further investigate,this paper develops an integrated approach combining pressure and rate transient analysis for well interference diagnosis considering CFNs.To perform multi-well simulation considering CFNs,non-intrusive embedded discrete fracture model approach was applied for coupling fracture with reservoir models.The impact of CFN including natural fractures and frac-hits on pressure and rate transient behavior in multi-well system was investigated.On a logelog plot,interference flow and compound linear flow are two new flow regimes caused by nearby producers.When both NFs and frac-hits are present in the reservoir,frac-hits have a greater impact on well#1 which contains frac-hits,and NFs have greater impact on well#3 which does not have frac-hits.For all well producing circumstances,it might be challenging to see divergence during pseudosteady state flow brought on by frac-hits on the logelog plot.Besides,when NFs occur,reservoir depletion becomes noticeable in comparison to frac-hits in pressure distribution.Application of this integrated approach demonstrates that it works well to characterize the well interference among different multi-fractured horizontal wells in a well pad.Better reservoir evaluation can be acquired based on the new features observed in the novel model,demonstrating the practicability of the proposed approach.The findings of this study can help for better evaluating well interference degree in multi-well systems combing PTA and RTA,which can reduce the uncertainty and improve the accuracy of the well interference analysis based on both field pressure and rate data.展开更多
In order to understand the mechanical properties and the fracture surface roughness characteristics of thermally damaged granite under dynamic splitting,dynamic Brazilian splitting tests were conducted on granite samp...In order to understand the mechanical properties and the fracture surface roughness characteristics of thermally damaged granite under dynamic splitting,dynamic Brazilian splitting tests were conducted on granite samples after thermal treatment at 25,200,400,and 600℃.Results show that the dynamic peak splitting strength of thermally damaged granite samples increases with increasing strain rate,showing obvious strain‐rate sensitivity.With increasing temperature,thermally induced cracks in granite transform from intergranular cracks to intragranular cracks,and to a transgranular crack network.Thermally induced damages reduce the dynamic peak splitting strength and the maximum absorbed energy while increasing the peak radial strain.The fracture mode of the thermally damaged granite under dynamic loads is mode Ⅱ splitting failure.By using the axial roughness index Z2 a,the distribution ranges of the wedge‐shaped failure zones and the tensile failure zones in the fracture surfaces under dynamic Brazilian splitting can be effectively identified.The radial roughness index Z_(2)^(r)is sensitive to the strain rate and temperature.It shows a linear correlation with the peak splitting strength and the maximum absorbed energy and a linear negative correlation with the peak radial strain.Z_(2)^(r)can be used to quantitatively estimate the dynamic parameters based on the models proposed.展开更多
In the last years,shale gas has gradually substituted oil and coal as the main sources of energy in the world.Compared with shallow shale gas reservoirs,deep shale is characterized by low permeability,low porosity,str...In the last years,shale gas has gradually substituted oil and coal as the main sources of energy in the world.Compared with shallow shale gas reservoirs,deep shale is characterized by low permeability,low porosity,strong heterogeneity,and strong anisotropy.In the process of multi-cluster fracturing of horizontal wells,the whole deformation process and destruction modes are significantly influenced by loading rates.In this investigation,the servo press was used to carry out semi-circular bend(SCB)mixedmode fracture experiments in deep shales(130,160,190℃)with prefabricated fractures under different loading rates(0.02,0.05,0.1,0.2 mm/min).The fracture propagation process was monitored using acoustic emission.The deformation characteristics,displacementeload curve,and acoustic emission parameters of shale under different loading rates were studied during the mixed-mode fracture propagation.Our results showed that during the deformation and fracture of the specimen,the acoustic emission energy and charge significantly increased near the stress peak,showing at this point the most intense acoustic emission activity.With the increase in loading rate,the fracture peak load of the deep shale specimen also increased.However,the maximum displacement decreased to different extents.With the increase in temperature,the effective fracture toughness of the deep shale gradually decreased.Also,the maximum displacement decreased.Under different loading rates,the deformation of the prefabricated cracks showed a nonlinear slow growthelinear growth trend.The slope of the linear growth stage increased with the increase in loading rate.In addition,as the loading rate increased,an increase in tension failure and a decrease in shear failure were observed.Moreover,the control chart showing the relationship between tension and the shear failure under different temperatures and loading rates was determined.展开更多
The frictional rupture mechanisms of rock discontinuities considering the dynamic load disturbance still remain unclear.This paper investigates the transitional behaviors of slip events happened on a planar granite fr...The frictional rupture mechanisms of rock discontinuities considering the dynamic load disturbance still remain unclear.This paper investigates the transitional behaviors of slip events happened on a planar granite fracture under cyclic normal stress with diferent oscillation amplitudes.The experimental results show that the activations of fast slips always correlate with unloading of normal stress.Besides,the intensive normal stress oscillation can weaken the shear strength which is recoverable when the normal stress return to constant.The rupture patterns are quantifed by stress drop,slip length and slip velocity.With the efect of small oscillation amplitudes,the slip events show chaotic shapes,compared to the regular and predictable style under constant normal stress.When the amplitude is large enough,the big and small slip events emerge alternately,showing a compound slip style.Large amplitude of the cyclic normal stress also widens the interval diferences of the slip events.This work provides experimental supports for a convincible link between the dynamic stress disturbance and the slip behavior of rock fractures.展开更多
This paper investigates the frictional behavior of the infilled rock fracture under dynamic normal stress.A series of direct shear tests were conducted on saw-cut granite fractures infilled with quartz using a selfdev...This paper investigates the frictional behavior of the infilled rock fracture under dynamic normal stress.A series of direct shear tests were conducted on saw-cut granite fractures infilled with quartz using a selfdeveloped dynamic shear apparatus,and the effects of normal load oscillation amplitude,normal load oscillation period and sliding velocity were studied.The test results reveal that the shear response can be divided into three stages over a whole loading-unloading process,characterized by different time spans and stress variations.Generally,a smaller oscillation amplitude,a longer oscillation period and a fast shear velocity promote the stability of the friction system,which is also confirmed by the Coulomb failure criterion calculated based on the observed periodic apparent friction coefficient.The dynamic strengthening/weakening phenomenon is dependent on the oscillation amplitude and product of sliding velocity and oscillation period(vT).Also,the rate and state friction law incorporating the parameter a that characterizes the normal stress variation is employed to describe the dynamic friction coefficient but exhibits an incompetent performance when handling intensive variation in normal stress.Finally,the potential seismicity induced by oscillating normal stress based on the observed stress drop is analyzed.This work helps us understand the sliding process and stability evolution of natural faults,and its benefits for relative hazard mitigation.展开更多
The effect of loading rate on the dynamic fracture properties and the failure mechanisms of glass fiber-reinforced composite materials under mode I fracture is studied. Dynamic reflective caustic experiments are carr...The effect of loading rate on the dynamic fracture properties and the failure mechanisms of glass fiber-reinforced composite materials under mode I fracture is studied. Dynamic reflective caustic experiments are carried out for two loading rates. By measuring the characteristic dimensions of the shadow spots during the caustic experiments, the dynamic SIFs are calculated for different loading rates. The experimental results indicate that the dynamic fracture toughness Kid increases remarkably with increasing loading rate, and the crack grows faster under the high-velocity impact. Moreover, by examining the crack growth routes and the fracture surfaces, it is shown that the loading rate also greatly affects the failure mechanisms at micro-scale.展开更多
In this study,the effect of loading rate on shale fracture behaviors was investigated under dynamic and static loading conditions.Cracked straight through Brazilian disc(CSTBD)shale specimens were tested with a split ...In this study,the effect of loading rate on shale fracture behaviors was investigated under dynamic and static loading conditions.Cracked straight through Brazilian disc(CSTBD)shale specimens were tested with a split Hopkinson pressure bar(SHPB)setup and INSTRON1346 servo-testing machine under pure mode I loading conditions.During the test,the crack propagation process was recorded by high-speed(HS)camera,and the acoustic emission(AE)signal generated by the fracture was collected by acoustic emission(AE)system.At the same time,crack propagation gauge(CPG)was used to measure the crack propagation velocity of the specimen.The results show that the crack propagation velocity and fracture toughness of shale have a positive correlation with the loading rate.The relationship among the crack propagation velocity,the fracture toughness and the loading rate is established under the static loading condition.In addition,the characteristics of AE signals with different loading rates are analyzed.It is found that the AE signals generated by microcrack growth decrease with the increase of loading rates.Meanwhile,the turning point of cumulative counting moves forward as the loading rate increases,which shows that the AE signal generated by shale fracture at low loading rate mainly comes from the initiation and propagation of microcracks,while at high loading rate it mainly comes from the formation of macro large-scale cracks.The fracture mechanism that causes shale fracture toughness and crack propagation velocity to vary with loading rate is also discussed based on the analysis results of AE signals.展开更多
The three-point bending experiments were applied to investigating effects of loading rates on fracture toughness of Huanglong limestone. The fracture toughness of Huanglong limestone was measured over a wide range of ...The three-point bending experiments were applied to investigating effects of loading rates on fracture toughness of Huanglong limestone. The fracture toughness of Huanglong limestone was measured over a wide range of loading rates from 9 × 10-4 to 1.537 MPa.m1/2/s. According to the approximate relationship between static and dynamic fracture toughness of Huanglong limestone, relationship between the growth velocity of crack and dynamic fracture toughness was obtained. The main conclusions are summarized as follows. （1） When the loading rate is higher than 0.027 MPa-ml/2/s, the fracture toughness of Huanglong limestone increases markedly with increasing loading rate. However, when loading rate is lower than 0.027 MPa-ml/2/s, fracture toughness slightly increases with an increase in loading rate. （2） It is found from experimental results that fracture toughness is linearly proportional to the logarithmic expression of loading rate. （3） For Huanglong limestone, when the growth velocity of crack is lower than 100 m/s, the energy release rate slightly decreases with increasing the growth velocity of crack. However, when the growth velocity of crack is higher than 1 000 m/s, the energy release rate dramatically decreases with an increase in the crack growth velocity.展开更多
The former studies indicate that loading rates significantly affect dynamic behavior of brittle materials,for instance,the dynamic compressive and tensile strength increase with loading rates.However,there still are m...The former studies indicate that loading rates significantly affect dynamic behavior of brittle materials,for instance,the dynamic compressive and tensile strength increase with loading rates.However,there still are many unknown or partially unknown aspects.For example,whether loading rates have effect on crack dynamic propagating behavior(propagation toughness,velocity and arrest,etc).To further explore the effect of loading rates on crack dynamic responses,a large-size single-cleavage trapezoidal open(SCTO)specimen was proposed,and impacting tests using the SCTO specimen under drop plate impact were conducted.Crack propagation gauges(CPGs)were employed in measuring impact loads,crack propagation time and velocities.In order to verify the testing result,the corresponding numerical model was established using explicit dynamic software AUTODYN,and the simulation result is basically consistent with the experimental results.The ABAQUS software was used to calculate the dynamic SIFs.The universal function was calculated by fractal method.The experimental-numerical method was employed in determining initiation toughness and propagation toughness.The results indicate that crack propagating velocities,dynamic fracture toughness and energy release rates increase with loading rates;crack delayed initiation time decreases with loading rates.展开更多
BACKGROUND Evidence-based guidance on return to sport following toe phalanx fractures is limited.AIM To systemically review all studies recording return to sport following toe phalanx fractures(both acute fractures an...BACKGROUND Evidence-based guidance on return to sport following toe phalanx fractures is limited.AIM To systemically review all studies recording return to sport following toe phalanx fractures(both acute fractures and stress fractures),and to collate information on return rates to sport(RRS)and mean return times(RTS)to the sport.METHODS A systematic search of PubMed,MEDLINE,EMBASE,CINAHL,Cochrane Library,Physiotherapy Evidence Database,and Google Scholar was performed in December 2022 using the keywords‘Toe’,‘Phalanx’,‘Fracture’,‘injury’,‘athletes’,‘sports’,‘non-operative’,‘conservative’,‘operative’,‘return to sport’.All studies which recorded RRS and RTS following toe phalanx fractures were included.RESULTS Thirteen studies were included:one retrospective cohort study and twelve case series.Seven studies reported on acute fractures.Six studies reported on stress fractures.For the acute fractures(n=156),63 were treated with primary conservative management(PCM),6 with primary surgical management(PSM)(all displaced intra-articular(physeal)fractures of the great toe base of the proximal phalanx),1 with secondary surgical management(SSM)and 87 did not specify treatment modality.For the stress fractures(n=26),23 were treated with PCM,3 with PSM,and 6 with SSM.For acute fractures,RRS with PCM ranged from 0 to 100%,and RTS with PCM ranged from 1.2 to 24 wk.For acute fractures,RRS with PSM were all 100%,and RTS with PSM ranged from 12 to 24 wk.One case of an undisplaced intra-articular(physeal)fracture treated conservatively required conversion to SSM on refracture with a return to sport.For stress fractures,RRS with PCM ranged from 0%to 100%,and RTS with PCM ranged from 5 to 10 wk.For stress fractures,RRS with PSM were all 100%,and RTS with surgical management ranged from 10 to 16 wk.Six cases of conservatively-managed stress fractures required conversion to SSM.Two of these cases were associated with a prolonged delay to diagnosis(1 year,2 years)and four cases with an underlying deformity[hallux valgus(n=3),claw toe(n=1)].All six cases returned to the sport after SSM.CONCLUSION The majority of sport-related toe phalanx fractures(acute and stress)are managed conservatively with overall satisfactory RRS and RTS.For acute fractures,surgical management is indicated for displaced,intra-articular(physeal)fractures,which offers satisfactory RRS and RTS.For stress fractures,surgical management is indicated for cases with delayed diagnosis and established nonunion at presentation,or with significant underlying deformity:both can expect satisfactory RRS and RTS.展开更多
Friction stir welding （FSW） was performed on 2024-T351 aluminum alloy plates. Metallographic analysis, Vickers microhardness and XRD tests were conducted to determine the properties of the welded zone. FE simulatio...Friction stir welding （FSW） was performed on 2024-T351 aluminum alloy plates. Metallographic analysis, Vickers microhardness and XRD tests were conducted to determine the properties of the welded zone. FE simulation of the FSW process was implemented for the different welding conditions to extract the residual stress and stress intensity factor （SIF）. Fracture and fatigue behaviors of the welds which have the initial crack in the nugget zone and the crack orientation along the welding direction, were studied based on standard test methods. Fracture behavior of the welds was also evaluated by shearography method. The results showed that the tool rotational and traverse speeds affect the fracture toughness and fatigue crack growth rate. FSW provides 18%-49% reductions in maximum fracture load and fracture toughness. A slight diminution in fracture toughness of the joints was observed for lower traverse speed of the tool, and at higher traverse or rotational speeds, increasing the probability of defects may contribute to low fracture toughness. Fatigue crack propagation rate of all welds was slower than that of the base metal for low values of stress intensity factor range ΔK （ΔK〈13 MPa·m^1/2）, but is much faster for high values of ΔK.展开更多
A numerical model of hydraulic fracture propagation is introduced for a representative reservoir(Yuanba continental tight sandstone gas reservoir in Northeast Sichuan).Different parameters are considered,i.e.,the inte...A numerical model of hydraulic fracture propagation is introduced for a representative reservoir(Yuanba continental tight sandstone gas reservoir in Northeast Sichuan).Different parameters are considered,i.e.,the interlayer stress difference,the fracturing discharge rate and the fracturing fluid viscosity.The results show that these factors affect the gas and water production by influencing the fracture size.The interlayer stress difference can effectively control the fracture height.The greater the stress difference,the smaller the dimensionless reconstruction volume of the reservoir,while the flowback rate and gas production are lower.A large displacement fracturing construction increases the fracture-forming efficiency and expands the fracture size.The larger the displacement of fracturing construction,the larger the dimensionless reconstruction volume of the reservoir,and the higher the fracture-forming efficiency of fracturing fluid,the flowback rate,and the gas production.Low viscosity fracturing fluid is suitable for long fractures,while high viscosity fracturing fluid is suitable for wide fractures.With an increase in the fracturing fluid viscosity,the dimensionless reconstruction volume and flowback rate of the reservoir display a non-monotonic behavior,however,their changes are relatively small.展开更多
Densification is a major feature of silica glass that has received widespread attention.This work investigates the fracture behavior of densified silica glass upon uniaxial tension based on atomistic simulations.It is...Densification is a major feature of silica glass that has received widespread attention.This work investigates the fracture behavior of densified silica glass upon uniaxial tension based on atomistic simulations.It is shown that the tensile strength of the silica glass approximately experiences a parabolic reduction with the initial density,while the densified samples show a faster power growth with the increase of strain rate.Meanwhile,the fracture strain and strain energy increase significantly when the densification exceeds a certain threshold,but fracture strain tends to the same value and strain energy becomes closer for different densified samples at extreme high strain rate.Microscopic views indicate that all the cracks are formed by the aggregation of nanoscale voids.The transition from brittleness fracture to ductility fracture can be found with the increase of strain rate,as a few fracture cracks change into a network distribution of many small cracks.Strikingly,for the high densified sample,there appears an evident plastic flow before fracture,which leads to the crack number less than the normal silica glass at the high strain rate.Furthermore,the coordinated silicon analysis suggests that high strain rate tension will especially lead to the transition from 4-to 3-fold Si when the high densified sample is in plastic flow.展开更多
Deep and ultra-deep reservoirs have dense matrix and high fracture pressure, which leads to high pressure and difficulty in fracturing construction. Conventional aggravated fracturing fluids have the problems of low a...Deep and ultra-deep reservoirs have dense matrix and high fracture pressure, which leads to high pressure and difficulty in fracturing construction. Conventional aggravated fracturing fluids have the problems of low aggravation efficiency, high friction resistance, etc., and the reduction of construction pressure cannot reach the theoretical effect. In view of the above problems, this paper adopts the weighting agent HD160 and the drag reducing agent JHFR-2 to form a new type of weighted slippery water fracturing fluid system. And the weighting performance, drag reduction performance, corrosion performance, anti-expansion performance and reservoir damage of this system were studied. The results show that the density of the system is adjustable within 1.1 - 1.6 g·cm−3, and the drag reduction rate can be up to 68% at 1.5 g·cm−3, with low corrosion rate, surface tension less than 28 mN·m−1, anti-expansion rate as high as 94.5%, and the damage rate of the reservoir permeability is less than 10%, which is of good application prospect.展开更多
The relation between loading rate and fracture velocity is the key to determining the fracture toughness of rock mass under dynamic loading.While designing an optimal blast design for any limestone mines,understanding...The relation between loading rate and fracture velocity is the key to determining the fracture toughness of rock mass under dynamic loading.While designing an optimal blast design for any limestone mines,understanding the relationship between blast detonation pressure and rock fragmentation can increase the energy utilisation in any limestone mine blast.The detonation pressure is directly related to dynamic loading rate and fracture velocity is directly related to stress wave propagation speed during blasting.This paper discusses the relationship between dynamic loading rate and fracture velocity for limestone samples.It was observed that crack propagation velocity increases with fracture toughness of rock samples.It may be concluded that as the dynamic loading increases,the fracture velocity increases.展开更多
Objective:To analyze the effect of locking compression plate on the success rate of operation and the time of postoperative recovery.Methods:120 patients with limb fractures from March 2018 to March 2020 were randomly...Objective:To analyze the effect of locking compression plate on the success rate of operation and the time of postoperative recovery.Methods:120 patients with limb fractures from March 2018 to March 2020 were randomly divided into control group(60 cases)and observation group(60 cases).The control group was treated with plate screw internal fixation,The observation group used locking compression plate internal fixation,Compare the effect of treatment,the success rate of operation and the time of postoperative recovery.results:compared the effective rate of the two groups,the observation group(93.33%)was significantly higher than the control group(75.00%).Compared with the two groups,the success rate of operation and the time of postoperative recovery,the observed composition power was higher than that of the control group,and the postoperative recovery time was lower than that of the control group,P<0.05.Conclusion:The use of locking compression plate for the treatment of limb fracture can significantly increase the probability of successful operation,shorten the recovery time after operation,the overall curative effect is ideal,and the clinical popularization value is high.展开更多
By means of reasonable assumption and mathematical derivation, a theoretic expression of flow rate for a single fracture with linearly varying width was obtained. The mathematical derivation was based on the cubic law...By means of reasonable assumption and mathematical derivation, a theoretic expression of flow rate for a single fracture with linearly varying width was obtained. The mathematical derivation was based on the cubic law and the new theoretic expression was an extention of traditional parallel plate model. This study may help to analyze seepage in fractured rock mass.展开更多
Experimental studies were conducted on the tensile behaviors and fracture modes of TiAl（Ti-46.5Al-2Nb-2Cr） alloys with near gamma（NG） equiaxed and near lamellar（NL） microstructures over a temperature range from ...Experimental studies were conducted on the tensile behaviors and fracture modes of TiAl（Ti-46.5Al-2Nb-2Cr） alloys with near gamma（NG） equiaxed and near lamellar（NL） microstructures over a temperature range from room temperature to 840 ℃ and a strain rate range of 0.001-1 350 s-1.The results indicate that the alloys are both temperature and strain rate dependent and they have a similar dependence.The dynamic strength is higher than the quasi-static strength but almost insensitive to high strain rate range of 320-1 350 s-1.The brittle-to-ductile transition temperature（BDTT） increases with increasing strain rates.NG TiAl yields obviously,while NL TiAl does not.Below BDTT,as the temperature increases,the fracture modes of the two alloys change from planar cleavage fracture to a mixture of transgranular and intergranular fractures,and finally to totally intergranular fracture.展开更多
AIM To systemically review all studies reporting return to sport following tibial plateau fracture, in order to provide information on return rates and times to sport, and to assess variations in sporting outcome for ...AIM To systemically review all studies reporting return to sport following tibial plateau fracture, in order to provide information on return rates and times to sport, and to assess variations in sporting outcome for different treatment methods.METHODS A systematic search of CINAHAL, Cochrane, EMBASE, Google Scholar, MEDLINE, PEDro, Scopus, SPORTDiscus and Web of Science was performed in January 2017 using the keywords "tibial", "plateau", "fractures", "knee", "athletes", "sports", "non-operative", "conservative", "operative", "return to sport". All studies which recorded return rates and times to sport following tibial plateau fractures were included. RESULTS Twenty-seven studies were included: 1 was a randomised controlled trial, 7 were prospective cohort studies, 16 were retrospective cohort studies, 3 were case series. One study reported on the outcome of conservative management(n = 3); 27 reported on the outcome of surgical management(n = 917). Nine studies reported on Open Reduction Internal Fixation(ORIF)(n = 193), 11 on Arthroscopic-Assisted Reduction Internal Fixation(ARIF)(n = 253) and 7 on Frame-Assisted Fixation(FRAME)(n = 262). All studies recorded "return to sport"rates. Only one study recorded a "return to sport" time. The return rate to sport for the total cohort was 70%. For the conservatively-managed fractures, the return rate was 100%. For the surgically-managed fractures, the return rate was 70%. For fractures managed with ORIF, the return rate was 60%. For fractures managed with ARIF, the return rate was 83%. For fractures managed with FRAME was 52%. The return rate for ARIF was found to be significantly greater than that for ORIF(OR 3.22, 95%CI: 2.09-4.97, P < 0.001) and for FRAME(OR 4.33, 95%CI: 2.89-6.50, P < 0.001). No difference was found between the return rates for ORIF and FRAME(OR 1.35, 95%CI: 0.92-1.96, P = 0.122). The recorded return time was 6.9 mo(median), from a study reporting on ORIF.CONCLUSION Return rates to sport for tibial plateau fractures remain limited compared to other fractures. ARIF provides the best return rates. There is limited data regarding return times to sport. Further research is required to determine return times to sport, and to improve return rates to sport, through treatment and rehabilitation optimisation.展开更多
基金supported by National Nature Science Foundation of China (Grant No.42177157)the Science and Technology Program of Liaoning Province (Grant No.2023JH1/10400003)the Applied Basic Research Programof Liaoning Province (Grant No.2023JH2/101300153).
文摘The injection of large volumes of natural gas into geological formations,as is required for underground gas storage,leads to alterations in the effective stress exerted on adjacent faults.This increases the potential for their reactivation and subsequent earthquake triggering.Most measurements of the frictional properties of rock fractures have been conducted under normal and shear stresses.However,faults in gas storage facilities exist within a true three-dimensional(3D)stress state.A double-direct shear experiment on rock fractures under both lateral and normal stresses was conducted using a true triaxial loading system.It was observed that the friction coefficient increases with increasing lateral stress,but decreases with increasing normal stress.The impact of lateral and normal stresses on the response is primarily mediated through their influence on the initial friction coefficient.This allows for an empirical modification of the rate-state friction model that considers the influence of lateral and normal stresses.The impact of lateral and normal stresses on observed friction coefficients is related to the propensity for the production of wear products on the fracture surfaces.Lateral stresses enhance the shear strength of rock(e.g.Mogi criterion).This reduces asperity breakage and the generation of wear products,and consequently augments the friction coefficient of the surface.Conversely,increased normal stresses inhibit dilatancy on the fracture surface,increasing the breakage of asperities and the concomitant production of wear products that promote rolling deformation.This ultimately reduces the friction coefficient.
基金The authors are grateful to the financial support from China Postdoctoral Science Foundation(2022M712645)Opening Fund of Key Laboratory of Enhanced Oil Recovery(Northeast Petroleum University),Ministry of Education(NEPU-EOR-2021-03).
文摘Severe well interference through complex fracture networks(CFNs)can be observed among multi-well pads in low permeability reservoirs.The well interference analysis between multi-fractured horizontal wells(MFHWs)is vitally important for reservoir effective development.Well interference has been historically investigated by pressure transient analysis,while it has shown that rate transient analysis has great potential in well interference diagnosis.However,the impact of complex fracture networks(CFNs)on rate transient behavior of parent well and child well in unconventional reservoirs is still not clear.To further investigate,this paper develops an integrated approach combining pressure and rate transient analysis for well interference diagnosis considering CFNs.To perform multi-well simulation considering CFNs,non-intrusive embedded discrete fracture model approach was applied for coupling fracture with reservoir models.The impact of CFN including natural fractures and frac-hits on pressure and rate transient behavior in multi-well system was investigated.On a logelog plot,interference flow and compound linear flow are two new flow regimes caused by nearby producers.When both NFs and frac-hits are present in the reservoir,frac-hits have a greater impact on well#1 which contains frac-hits,and NFs have greater impact on well#3 which does not have frac-hits.For all well producing circumstances,it might be challenging to see divergence during pseudosteady state flow brought on by frac-hits on the logelog plot.Besides,when NFs occur,reservoir depletion becomes noticeable in comparison to frac-hits in pressure distribution.Application of this integrated approach demonstrates that it works well to characterize the well interference among different multi-fractured horizontal wells in a well pad.Better reservoir evaluation can be acquired based on the new features observed in the novel model,demonstrating the practicability of the proposed approach.The findings of this study can help for better evaluating well interference degree in multi-well systems combing PTA and RTA,which can reduce the uncertainty and improve the accuracy of the well interference analysis based on both field pressure and rate data.
基金supported by the National Natural Science Foundation of China(52174071,U1903216,52004052)the National Key R&D Program of China(2022YFC2903903).
文摘In order to understand the mechanical properties and the fracture surface roughness characteristics of thermally damaged granite under dynamic splitting,dynamic Brazilian splitting tests were conducted on granite samples after thermal treatment at 25,200,400,and 600℃.Results show that the dynamic peak splitting strength of thermally damaged granite samples increases with increasing strain rate,showing obvious strain‐rate sensitivity.With increasing temperature,thermally induced cracks in granite transform from intergranular cracks to intragranular cracks,and to a transgranular crack network.Thermally induced damages reduce the dynamic peak splitting strength and the maximum absorbed energy while increasing the peak radial strain.The fracture mode of the thermally damaged granite under dynamic loads is mode Ⅱ splitting failure.By using the axial roughness index Z2 a,the distribution ranges of the wedge‐shaped failure zones and the tensile failure zones in the fracture surfaces under dynamic Brazilian splitting can be effectively identified.The radial roughness index Z_(2)^(r)is sensitive to the strain rate and temperature.It shows a linear correlation with the peak splitting strength and the maximum absorbed energy and a linear negative correlation with the peak radial strain.Z_(2)^(r)can be used to quantitatively estimate the dynamic parameters based on the models proposed.
基金supported by the National Natural Science Foundation of China(No.52204007)the Natural Science Foundation of Heilongjiang Province of China(YQ2021E005)+1 种基金New Era Longjiang Outstanding Master's and Doctoral Thesis Project(LJYXL2022-002)Key Laboratory of Enhanced Oil and Gas Recovery,Ministry of Education(NEPU-EOR-2022-04).
文摘In the last years,shale gas has gradually substituted oil and coal as the main sources of energy in the world.Compared with shallow shale gas reservoirs,deep shale is characterized by low permeability,low porosity,strong heterogeneity,and strong anisotropy.In the process of multi-cluster fracturing of horizontal wells,the whole deformation process and destruction modes are significantly influenced by loading rates.In this investigation,the servo press was used to carry out semi-circular bend(SCB)mixedmode fracture experiments in deep shales(130,160,190℃)with prefabricated fractures under different loading rates(0.02,0.05,0.1,0.2 mm/min).The fracture propagation process was monitored using acoustic emission.The deformation characteristics,displacementeload curve,and acoustic emission parameters of shale under different loading rates were studied during the mixed-mode fracture propagation.Our results showed that during the deformation and fracture of the specimen,the acoustic emission energy and charge significantly increased near the stress peak,showing at this point the most intense acoustic emission activity.With the increase in loading rate,the fracture peak load of the deep shale specimen also increased.However,the maximum displacement decreased to different extents.With the increase in temperature,the effective fracture toughness of the deep shale gradually decreased.Also,the maximum displacement decreased.Under different loading rates,the deformation of the prefabricated cracks showed a nonlinear slow growthelinear growth trend.The slope of the linear growth stage increased with the increase in loading rate.In addition,as the loading rate increased,an increase in tension failure and a decrease in shear failure were observed.Moreover,the control chart showing the relationship between tension and the shear failure under different temperatures and loading rates was determined.
基金supported by Fundamental Research Funds for the Central Universities(22dfx06)Natural Science Foundation of Guangdong Province-Joint Program for Ofshore Wind Power(2022A1515240009).
文摘The frictional rupture mechanisms of rock discontinuities considering the dynamic load disturbance still remain unclear.This paper investigates the transitional behaviors of slip events happened on a planar granite fracture under cyclic normal stress with diferent oscillation amplitudes.The experimental results show that the activations of fast slips always correlate with unloading of normal stress.Besides,the intensive normal stress oscillation can weaken the shear strength which is recoverable when the normal stress return to constant.The rupture patterns are quantifed by stress drop,slip length and slip velocity.With the efect of small oscillation amplitudes,the slip events show chaotic shapes,compared to the regular and predictable style under constant normal stress.When the amplitude is large enough,the big and small slip events emerge alternately,showing a compound slip style.Large amplitude of the cyclic normal stress also widens the interval diferences of the slip events.This work provides experimental supports for a convincible link between the dynamic stress disturbance and the slip behavior of rock fractures.
基金the National Natural Science Foundation of China(Nos.51904359,51978677 and 52111530089)the Guangdong Provincial Department of Science and Technology(No.2019ZT08G090)+2 种基金the Enhanced National Key Basic Research Program(No.2019-JCJQ-ZD-352-00-04)the Science and Technology Program for Sustainable Development of Shenzhen(No.KCXFZ202002011008532)the Open Research Fund of the State Key Laboratory of Coal Resources and Safe Mining,CUMT(No.SKLCRSM20KF002).
文摘This paper investigates the frictional behavior of the infilled rock fracture under dynamic normal stress.A series of direct shear tests were conducted on saw-cut granite fractures infilled with quartz using a selfdeveloped dynamic shear apparatus,and the effects of normal load oscillation amplitude,normal load oscillation period and sliding velocity were studied.The test results reveal that the shear response can be divided into three stages over a whole loading-unloading process,characterized by different time spans and stress variations.Generally,a smaller oscillation amplitude,a longer oscillation period and a fast shear velocity promote the stability of the friction system,which is also confirmed by the Coulomb failure criterion calculated based on the observed periodic apparent friction coefficient.The dynamic strengthening/weakening phenomenon is dependent on the oscillation amplitude and product of sliding velocity and oscillation period(vT).Also,the rate and state friction law incorporating the parameter a that characterizes the normal stress variation is employed to describe the dynamic friction coefficient but exhibits an incompetent performance when handling intensive variation in normal stress.Finally,the potential seismicity induced by oscillating normal stress based on the observed stress drop is analyzed.This work helps us understand the sliding process and stability evolution of natural faults,and its benefits for relative hazard mitigation.
基金supported by the National Natural Science Foundation of China (No.10672002).
文摘The effect of loading rate on the dynamic fracture properties and the failure mechanisms of glass fiber-reinforced composite materials under mode I fracture is studied. Dynamic reflective caustic experiments are carried out for two loading rates. By measuring the characteristic dimensions of the shadow spots during the caustic experiments, the dynamic SIFs are calculated for different loading rates. The experimental results indicate that the dynamic fracture toughness Kid increases remarkably with increasing loading rate, and the crack grows faster under the high-velocity impact. Moreover, by examining the crack growth routes and the fracture surfaces, it is shown that the loading rate also greatly affects the failure mechanisms at micro-scale.
基金Project(41630642)supported by the National Natural Science Foundation of China。
文摘In this study,the effect of loading rate on shale fracture behaviors was investigated under dynamic and static loading conditions.Cracked straight through Brazilian disc(CSTBD)shale specimens were tested with a split Hopkinson pressure bar(SHPB)setup and INSTRON1346 servo-testing machine under pure mode I loading conditions.During the test,the crack propagation process was recorded by high-speed(HS)camera,and the acoustic emission(AE)signal generated by the fracture was collected by acoustic emission(AE)system.At the same time,crack propagation gauge(CPG)was used to measure the crack propagation velocity of the specimen.The results show that the crack propagation velocity and fracture toughness of shale have a positive correlation with the loading rate.The relationship among the crack propagation velocity,the fracture toughness and the loading rate is established under the static loading condition.In addition,the characteristics of AE signals with different loading rates are analyzed.It is found that the AE signals generated by microcrack growth decrease with the increase of loading rates.Meanwhile,the turning point of cumulative counting moves forward as the loading rate increases,which shows that the AE signal generated by shale fracture at low loading rate mainly comes from the initiation and propagation of microcracks,while at high loading rate it mainly comes from the formation of macro large-scale cracks.The fracture mechanism that causes shale fracture toughness and crack propagation velocity to vary with loading rate is also discussed based on the analysis results of AE signals.
基金Projects(50490275, 50621403, 50778184) supported by the National Natural Science Foundation of ChinaProject(NCET-07-0911) supported by Program of New Century Talents of Ministry of EducationProject(CSTC, 2009BA4046) supported by the Natural Science Foundation of CQ CSTC
文摘The three-point bending experiments were applied to investigating effects of loading rates on fracture toughness of Huanglong limestone. The fracture toughness of Huanglong limestone was measured over a wide range of loading rates from 9 × 10-4 to 1.537 MPa.m1/2/s. According to the approximate relationship between static and dynamic fracture toughness of Huanglong limestone, relationship between the growth velocity of crack and dynamic fracture toughness was obtained. The main conclusions are summarized as follows. （1） When the loading rate is higher than 0.027 MPa-ml/2/s, the fracture toughness of Huanglong limestone increases markedly with increasing loading rate. However, when loading rate is lower than 0.027 MPa-ml/2/s, fracture toughness slightly increases with an increase in loading rate. （2） It is found from experimental results that fracture toughness is linearly proportional to the logarithmic expression of loading rate. （3） For Huanglong limestone, when the growth velocity of crack is lower than 100 m/s, the energy release rate slightly decreases with increasing the growth velocity of crack. However, when the growth velocity of crack is higher than 1 000 m/s, the energy release rate dramatically decreases with an increase in the crack growth velocity.
基金Projects(11672194,U19A2098)supported by the National Natural Science Foundation of ChinaProject(2018SCU12047)supported by Fundamental Research Funds for the Central Universities,ChinaProject(2018JZ0036)supported by the Project of Science and Technology of Sichuan Province,China。
文摘The former studies indicate that loading rates significantly affect dynamic behavior of brittle materials,for instance,the dynamic compressive and tensile strength increase with loading rates.However,there still are many unknown or partially unknown aspects.For example,whether loading rates have effect on crack dynamic propagating behavior(propagation toughness,velocity and arrest,etc).To further explore the effect of loading rates on crack dynamic responses,a large-size single-cleavage trapezoidal open(SCTO)specimen was proposed,and impacting tests using the SCTO specimen under drop plate impact were conducted.Crack propagation gauges(CPGs)were employed in measuring impact loads,crack propagation time and velocities.In order to verify the testing result,the corresponding numerical model was established using explicit dynamic software AUTODYN,and the simulation result is basically consistent with the experimental results.The ABAQUS software was used to calculate the dynamic SIFs.The universal function was calculated by fractal method.The experimental-numerical method was employed in determining initiation toughness and propagation toughness.The results indicate that crack propagating velocities,dynamic fracture toughness and energy release rates increase with loading rates;crack delayed initiation time decreases with loading rates.
文摘BACKGROUND Evidence-based guidance on return to sport following toe phalanx fractures is limited.AIM To systemically review all studies recording return to sport following toe phalanx fractures(both acute fractures and stress fractures),and to collate information on return rates to sport(RRS)and mean return times(RTS)to the sport.METHODS A systematic search of PubMed,MEDLINE,EMBASE,CINAHL,Cochrane Library,Physiotherapy Evidence Database,and Google Scholar was performed in December 2022 using the keywords‘Toe’,‘Phalanx’,‘Fracture’,‘injury’,‘athletes’,‘sports’,‘non-operative’,‘conservative’,‘operative’,‘return to sport’.All studies which recorded RRS and RTS following toe phalanx fractures were included.RESULTS Thirteen studies were included:one retrospective cohort study and twelve case series.Seven studies reported on acute fractures.Six studies reported on stress fractures.For the acute fractures(n=156),63 were treated with primary conservative management(PCM),6 with primary surgical management(PSM)(all displaced intra-articular(physeal)fractures of the great toe base of the proximal phalanx),1 with secondary surgical management(SSM)and 87 did not specify treatment modality.For the stress fractures(n=26),23 were treated with PCM,3 with PSM,and 6 with SSM.For acute fractures,RRS with PCM ranged from 0 to 100%,and RTS with PCM ranged from 1.2 to 24 wk.For acute fractures,RRS with PSM were all 100%,and RTS with PSM ranged from 12 to 24 wk.One case of an undisplaced intra-articular(physeal)fracture treated conservatively required conversion to SSM on refracture with a return to sport.For stress fractures,RRS with PCM ranged from 0%to 100%,and RTS with PCM ranged from 5 to 10 wk.For stress fractures,RRS with PSM were all 100%,and RTS with surgical management ranged from 10 to 16 wk.Six cases of conservatively-managed stress fractures required conversion to SSM.Two of these cases were associated with a prolonged delay to diagnosis(1 year,2 years)and four cases with an underlying deformity[hallux valgus(n=3),claw toe(n=1)].All six cases returned to the sport after SSM.CONCLUSION The majority of sport-related toe phalanx fractures(acute and stress)are managed conservatively with overall satisfactory RRS and RTS.For acute fractures,surgical management is indicated for displaced,intra-articular(physeal)fractures,which offers satisfactory RRS and RTS.For stress fractures,surgical management is indicated for cases with delayed diagnosis and established nonunion at presentation,or with significant underlying deformity:both can expect satisfactory RRS and RTS.
文摘Friction stir welding （FSW） was performed on 2024-T351 aluminum alloy plates. Metallographic analysis, Vickers microhardness and XRD tests were conducted to determine the properties of the welded zone. FE simulation of the FSW process was implemented for the different welding conditions to extract the residual stress and stress intensity factor （SIF）. Fracture and fatigue behaviors of the welds which have the initial crack in the nugget zone and the crack orientation along the welding direction, were studied based on standard test methods. Fracture behavior of the welds was also evaluated by shearography method. The results showed that the tool rotational and traverse speeds affect the fracture toughness and fatigue crack growth rate. FSW provides 18%-49% reductions in maximum fracture load and fracture toughness. A slight diminution in fracture toughness of the joints was observed for lower traverse speed of the tool, and at higher traverse or rotational speeds, increasing the probability of defects may contribute to low fracture toughness. Fatigue crack propagation rate of all welds was slower than that of the base metal for low values of stress intensity factor range ΔK （ΔK〈13 MPa·m^1/2）, but is much faster for high values of ΔK.
文摘A numerical model of hydraulic fracture propagation is introduced for a representative reservoir(Yuanba continental tight sandstone gas reservoir in Northeast Sichuan).Different parameters are considered,i.e.,the interlayer stress difference,the fracturing discharge rate and the fracturing fluid viscosity.The results show that these factors affect the gas and water production by influencing the fracture size.The interlayer stress difference can effectively control the fracture height.The greater the stress difference,the smaller the dimensionless reconstruction volume of the reservoir,while the flowback rate and gas production are lower.A large displacement fracturing construction increases the fracture-forming efficiency and expands the fracture size.The larger the displacement of fracturing construction,the larger the dimensionless reconstruction volume of the reservoir,and the higher the fracture-forming efficiency of fracturing fluid,the flowback rate,and the gas production.Low viscosity fracturing fluid is suitable for long fractures,while high viscosity fracturing fluid is suitable for wide fractures.With an increase in the fracturing fluid viscosity,the dimensionless reconstruction volume and flowback rate of the reservoir display a non-monotonic behavior,however,their changes are relatively small.
基金Project supported by Beijing Institute of Technology Research Fund Program for Young Scholars.
文摘Densification is a major feature of silica glass that has received widespread attention.This work investigates the fracture behavior of densified silica glass upon uniaxial tension based on atomistic simulations.It is shown that the tensile strength of the silica glass approximately experiences a parabolic reduction with the initial density,while the densified samples show a faster power growth with the increase of strain rate.Meanwhile,the fracture strain and strain energy increase significantly when the densification exceeds a certain threshold,but fracture strain tends to the same value and strain energy becomes closer for different densified samples at extreme high strain rate.Microscopic views indicate that all the cracks are formed by the aggregation of nanoscale voids.The transition from brittleness fracture to ductility fracture can be found with the increase of strain rate,as a few fracture cracks change into a network distribution of many small cracks.Strikingly,for the high densified sample,there appears an evident plastic flow before fracture,which leads to the crack number less than the normal silica glass at the high strain rate.Furthermore,the coordinated silicon analysis suggests that high strain rate tension will especially lead to the transition from 4-to 3-fold Si when the high densified sample is in plastic flow.
文摘Deep and ultra-deep reservoirs have dense matrix and high fracture pressure, which leads to high pressure and difficulty in fracturing construction. Conventional aggravated fracturing fluids have the problems of low aggravation efficiency, high friction resistance, etc., and the reduction of construction pressure cannot reach the theoretical effect. In view of the above problems, this paper adopts the weighting agent HD160 and the drag reducing agent JHFR-2 to form a new type of weighted slippery water fracturing fluid system. And the weighting performance, drag reduction performance, corrosion performance, anti-expansion performance and reservoir damage of this system were studied. The results show that the density of the system is adjustable within 1.1 - 1.6 g·cm−3, and the drag reduction rate can be up to 68% at 1.5 g·cm−3, with low corrosion rate, surface tension less than 28 mN·m−1, anti-expansion rate as high as 94.5%, and the damage rate of the reservoir permeability is less than 10%, which is of good application prospect.
文摘The relation between loading rate and fracture velocity is the key to determining the fracture toughness of rock mass under dynamic loading.While designing an optimal blast design for any limestone mines,understanding the relationship between blast detonation pressure and rock fragmentation can increase the energy utilisation in any limestone mine blast.The detonation pressure is directly related to dynamic loading rate and fracture velocity is directly related to stress wave propagation speed during blasting.This paper discusses the relationship between dynamic loading rate and fracture velocity for limestone samples.It was observed that crack propagation velocity increases with fracture toughness of rock samples.It may be concluded that as the dynamic loading increases,the fracture velocity increases.
文摘Objective:To analyze the effect of locking compression plate on the success rate of operation and the time of postoperative recovery.Methods:120 patients with limb fractures from March 2018 to March 2020 were randomly divided into control group(60 cases)and observation group(60 cases).The control group was treated with plate screw internal fixation,The observation group used locking compression plate internal fixation,Compare the effect of treatment,the success rate of operation and the time of postoperative recovery.results:compared the effective rate of the two groups,the observation group(93.33%)was significantly higher than the control group(75.00%).Compared with the two groups,the success rate of operation and the time of postoperative recovery,the observed composition power was higher than that of the control group,and the postoperative recovery time was lower than that of the control group,P<0.05.Conclusion:The use of locking compression plate for the treatment of limb fracture can significantly increase the probability of successful operation,shorten the recovery time after operation,the overall curative effect is ideal,and the clinical popularization value is high.
基金supported by the National Basic Research Program of China(2009CB219605)the National Natural Science Foundation of China(41074040)
文摘By means of reasonable assumption and mathematical derivation, a theoretic expression of flow rate for a single fracture with linearly varying width was obtained. The mathematical derivation was based on the cubic law and the new theoretic expression was an extention of traditional parallel plate model. This study may help to analyze seepage in fractured rock mass.
基金Projects(10902106,90505002)supported by the National Natural Science Foundation of China
文摘Experimental studies were conducted on the tensile behaviors and fracture modes of TiAl（Ti-46.5Al-2Nb-2Cr） alloys with near gamma（NG） equiaxed and near lamellar（NL） microstructures over a temperature range from room temperature to 840 ℃ and a strain rate range of 0.001-1 350 s-1.The results indicate that the alloys are both temperature and strain rate dependent and they have a similar dependence.The dynamic strength is higher than the quasi-static strength but almost insensitive to high strain rate range of 320-1 350 s-1.The brittle-to-ductile transition temperature（BDTT） increases with increasing strain rates.NG TiAl yields obviously,while NL TiAl does not.Below BDTT,as the temperature increases,the fracture modes of the two alloys change from planar cleavage fracture to a mixture of transgranular and intergranular fractures,and finally to totally intergranular fracture.
文摘AIM To systemically review all studies reporting return to sport following tibial plateau fracture, in order to provide information on return rates and times to sport, and to assess variations in sporting outcome for different treatment methods.METHODS A systematic search of CINAHAL, Cochrane, EMBASE, Google Scholar, MEDLINE, PEDro, Scopus, SPORTDiscus and Web of Science was performed in January 2017 using the keywords "tibial", "plateau", "fractures", "knee", "athletes", "sports", "non-operative", "conservative", "operative", "return to sport". All studies which recorded return rates and times to sport following tibial plateau fractures were included. RESULTS Twenty-seven studies were included: 1 was a randomised controlled trial, 7 were prospective cohort studies, 16 were retrospective cohort studies, 3 were case series. One study reported on the outcome of conservative management(n = 3); 27 reported on the outcome of surgical management(n = 917). Nine studies reported on Open Reduction Internal Fixation(ORIF)(n = 193), 11 on Arthroscopic-Assisted Reduction Internal Fixation(ARIF)(n = 253) and 7 on Frame-Assisted Fixation(FRAME)(n = 262). All studies recorded "return to sport"rates. Only one study recorded a "return to sport" time. The return rate to sport for the total cohort was 70%. For the conservatively-managed fractures, the return rate was 100%. For the surgically-managed fractures, the return rate was 70%. For fractures managed with ORIF, the return rate was 60%. For fractures managed with ARIF, the return rate was 83%. For fractures managed with FRAME was 52%. The return rate for ARIF was found to be significantly greater than that for ORIF(OR 3.22, 95%CI: 2.09-4.97, P < 0.001) and for FRAME(OR 4.33, 95%CI: 2.89-6.50, P < 0.001). No difference was found between the return rates for ORIF and FRAME(OR 1.35, 95%CI: 0.92-1.96, P = 0.122). The recorded return time was 6.9 mo(median), from a study reporting on ORIF.CONCLUSION Return rates to sport for tibial plateau fractures remain limited compared to other fractures. ARIF provides the best return rates. There is limited data regarding return times to sport. Further research is required to determine return times to sport, and to improve return rates to sport, through treatment and rehabilitation optimisation.
