2017, 45(10):1415-1420. DOI: 10.11908/j.issn.0253-374x.2017.10.001 CSTR:
Abstract:Seven thousand seven hundred and seventy eight ground motion records were collected. For each group of seismic ground motion, the spectral characteristics were analyzed. A type of ground motion clustering method based on energy distribution was introduced. According to this method, the records belonging to the same site type can be divided into three parts. For each group of seismic ground motion, the characteristic periods were proposed based on the Chinese seismic resistance code. Besides, the differences between the proposed value and the code value were analyzed. The research shows that, compared with the proposed values, the code characteristic periods of group 1 and group 2 are bigger, while the values of group 3 are smaller.
KE Shitang , WANG Hao , YU Wei
2017, 45(10):1421-1428. DOI: 10.11908/j.issn.0253-374x.2017.10.002 CSTR:
Abstract:With the world’s highest cooling tower (220 m) which is being built as the engineering background, the wind tunnel tests of pressure measurement under single tower condition and six typical group towers combinations were conducted. The influence laws of static, dynamic and extreme interference effects of different typical four towers combinations were discussed. The mathematical statistics method and frequency spectrum method were used for analyzing different influencing factors and mechanisms. Then, the formulas of interference factors for typical four towers combinations considering wind directions were given. Finally, based on comprehensive assessment of the interference effects of overall wind loads, the best scheme for the arrangement of the four towers in a row was proposed, which followed the arrangements in oblique Lshaped pattern, Lshaped pattern, rhombic pattern, and rectangular pattern successively. A strong linear correlation was found to exist between the characteristic angle α and the maximum FE of five typical fourtower arrangements.
SUN Feifei , TANG Zhiming , SUN Mi , LI Guoqiang
2017, 45(10):1429-1436. DOI: 10.11908/j.issn.0253-374x.2017.10.003 CSTR:
Abstract:In order to meet the requirements of fine and simplified hysteretic behavior simulation analysis of highstrength steel flush endplate connection, simulation methods based on solid element and zeroLength element were studied. Based on the solid element, implicit analysis and explicit analysis were conducted. The implicit analysis suffered from inability to converge. In the explicit analysis model, the rule of loading step was improved, and for each amplitude an independent loading step is assigned to minimize large discrepancy occurred in a single step with different amplitudes. Aimed at the zeroLength element, a modified quadrilinear line model was proposed. Two factors, i.e. the bending deformation of the bolts and the rotation of the beam flanges, which cannot be neglected for the highstrength steel flush endplate connection, were considered. The damage indices of the highstrength steel connection and the normal steel connection were different for the unloading stiffness and a simplified model based on the Pinching4 Model was established. The numerical simulation of the flushend plate connection shows that the simplified analysis model can well simulate the slip effect and the pinching effect in the experimental hysteresis behavior.
YUAN Juyun , JIANG Mingjing , LIAO Youbin , SUN Ya
2017, 45(10):1437-1445. DOI: 10.11908/j.issn.0253-374x.2017.10.004 CSTR:
Abstract:In order to guide indoor model experiments or numerical simulation directly and engineering practice indirectly, the process of rock cutting was simulated by using the DEM software where the reasonable contact model for rock summarized from the micro bond contact experiment was implanted. The influence of cutter width and rock sample size on the rock fragmentation was investigated. The results show that cutter width is too small to keep the stability of the actual TBM construction. However, large cutter width in small sample size has a significant boundary effect which affects the test result. In the indoor model test, there exists a critical ratio of the cutter width and the rock sample width (relative ratio). If the relative ratio in the test is less than the critical ratio, the boundary effect can be reduced during the test.
TANG Keshuang , YANG Bowen , XU Kai , SUN Zili , ZHOU Nan
2017, 45(10):1454-1461. DOI: 10.11908/j.issn.0253-374x.2017.10.006 CSTR:
Abstract:A trajectory prediction model and a driver’s hidden decisionmaking process prediction model were established based on the collection and analysis of vehicle trajectory data at intersection influenced areas. Moreover, based on these two models, the rules for recognizing driver’s risky behaviors were built. The three together constitute the overall driver’s risky behaviors prediction method at signalized intersections. It is found that the overall accuracy of this prediction method is 88.89%. This prediction method realizes vehicle’s individual dynamic trajectory prediction, utilizing driver’s hidden decisionmaking process as an important variable in prediction of driver’s risky behaviors.
SHAO Minhua , YUN Xiumeng , YUAN Yuqiao
2017, 45(10):1462-1468. DOI: 10.11908/j.issn.0253-374x.2017.10.007 CSTR:
Abstract:Using IRI (international roughness index) as a bridge, the quantitative relationship between RQI (ride quality index) and travel time cost was established. First, at different speeds, IRIs of fifty different roads were simulated by the use of dynamic equation of quartercar model. Next, the relationship between RQI and speed was obtained by the analysis of the relationship between RQI and IRI. Finally, the difference of RQIs at the same speed of 80 km?h-1 and the difference of speeds at the same RQI for any two of fifty roads were calculated. Good correlations were found between them. This result shows that the influence of RQI on travel time cost should not be ignored in the study of the behavior of travel choice or in the study of benefit evaluation of road maintenance.
2017, 45(10):1469-1475. DOI: 10.11908/j.issn.0253-374x.2017.10.008 CSTR:
Abstract:According to insufficient account of the proposed zoning rules in the city in previous researches of intercity trips, this paper proposed the corresponding access traffic network and the required variables of the city, district, town or subdistrict and block zone levels of the city. Furthermore, it provided the model of access utility and analyzed its difference of constitution with different zone levels. In addition, it put forward a method to analyze the difference among the zone levels by calculating the deviation of the access time and the total access cost in different zone level. It is concluded that the town or subdistrict zone is the reasonable zoning rule. Using the road network as the simplified bus network can meet the accuracy requirement, and reduce a lot of work. At last, through the case analysis, it verified the effectiveness of the method, and provided the basis for the prediction of share ratios of intercity trip.
YANG Xinwen , YAO Yiming , ZHOU Shunhua
2017, 45(10):1476-1482. DOI: 10.11908/j.issn.0253-374x.2017.10.009 CSTR:
Abstract:When wheel/rail contact problems are solved using nonHertz contact theory, the influencing numbers have more important effect on wheel/rail contact stress and contact patch. When a contact between wheel flange and rail gauge angle occurs, the influencing number of nonHertz contact theory based on elastic half space hypothesis is not applicable. Based on elastic full space hypothesis, a finite element method was presented to calculate wheel/rail contact influence number of nonHertz contact theory, and the nonHertz contact model was innovatively revised. As an example of wheel/rail contact profile of the CHN75 standard rail and LM standard wheel in China, under the calculation of high efficiency, two wheel/rail contact models (revised nonHertz method and wheel/rail profile partition model P_M (Partition Model) were used to calculate the wheel/rail normal contact stress and contact patch area when lateral displacement of the wheelset ranged from 0 mm to 8 mm. The results show that the influencing number calculated by finite element method is larger than that obtained by using BossinisqeCerruti formula. And the result calculated by finite element method on the rail gauge corner is larger than that on the top of the rail. The normal stress calculated by revised nonHertz theory is larger than that calculated by the P_M model, and the change of the normal contact stress and contact patch area calculated by two wheel/rail contact model is almost the same with the increase of the lateral displacement of the wheelset. When the lateral displacement of the wheelset is 0 to 4 mm, the maximum of the wheel/rail contact patch area is 173.75 mm2 and the wheel/rail contact profile is best matched. With the increase of the lateral displacement of the wheelset, the contact between the wheel flange and rail gauge corner will be produced and the wheel/rail contact area decreases while the normal contact stress increases dramatically.
LI Aiping , LU Jiaqing , ZHAO Yaxi , FAN Guoliang , XU Liyun
2017, 45(10):1483-1490. DOI: 10.11908/j.issn.0253-374x.2017.10.010 CSTR:
Abstract:To quantitatively describe the human reliability of manual station on engine assembly line within different working days and operation times, a model was proposed considering the shortest cognitive process, cognitive fatigue, and the shortest operation process. Based on the learningforgetting and fatiguerecovery theory, the cognitive time was developed with the shortest cognitive process and cognitive fatigue, while the operation time was developed with the shortest operation process. According to the cognitive time and operation time, fatigue failure rate was calculated and cognitive failure rate was introduced with the HCR(human cognitive reliability) method. After obtaining the failure coefficient according to their time variance, a human time variant reliability model was built. A case study verified the feasibility of the model. The result can be used in human reliability evaluation and product prediction.
2017, 45(10):1491-1497. DOI: 10.11908/j.issn.0253-374x.2017.10.011 CSTR:
Abstract:The effects of structure nonlinear on fullscale wind turbine blade static test were studied in this paper. First, the relationship between bending moment, strain, stiffness and deflection were theoretically analyzed. Then, fullscale blade was mounted on the test bench for extreme load static test. As the blade was deformed during the loading process, the loading angle, the radial, and tangential deflection of the blade were changed because of the blade structure nonlinear and torsional coupling. The loading force angle and arm were measured by using the triangular method. The strain gauges installed in the different section of the blade were used to measure the local strain on the blade. The results show that, compared with FEM target value, the maximum deviation of stiffness in 4 m away root during static test in flapwise direction is 48% and the maximum deviation of stiffness in 23 m away root in edgewise direction is 29%. The experimental results provide accurate stiffness data for numerical model of wind turbine to load calculations.
ZHOU Qicai , WU Qinglong , XIONG Xiaolei , JIAO Hongyu , ZHAO Jiong
2017, 45(10):1498-1505. DOI: 10.11908/j.issn.0253-374x.2017.10.012 CSTR:
Abstract:In order to achieve the layout optimization of web members of tower crane boom, a truss topology optimization method based on continuum was proposed. First, the optimization model was established by replacing web members with web plates. The web plates were divided into several subdomains so that the periodic SKO (soft kill option) method can be used for topology optimization of the slender boom. Next, element temperature filter function was added into the SKO method for the elimination of numerical instability like checkerboard. After getting the optimized topology of web plates, the skeleton extraction algorithm based on 8neighbourhood elements was employed to extract its skeleton and get optimized layout of web members. Based on three kinds of typical working conditions of QTZ63 tower crane, the optimization was conducted with consideration of hoisting dynamic load, wind load and inertial load. Finally, the optimized boom was proved to be effective by comparing with the original boom in strength, stiffness and stability under three typical working conditions.
LI Qiliang , DAI Wentong , DU Kaiyan , YANG Zhigang
2017, 45(10):1506-1511. DOI: 10.11908/j.issn.0253-374x.2017.10.013 CSTR:
Abstract:The static pressure coefficient and static pressure gradient are key parameters to estimate the flow quality of automotive wind tunnel test section. Numerical simulation was used along with wind tunnel test to study the influence of wind tunnel structure on static pressure coefficient and static pressure gradient of the test section. It is found that real results can be obtained by simulation of the static pressure coefficient and static pressure gradient using the computational model with two corners. No matter it is big or small nozzle, the static pressure coefficient and static pressure gradient corresponding to the collector height of 270 mm is the gentlest and the effective length of test section is the longest, which has the slightest impact on measurement. For the big nozzle, the static pressure coefficient and static pressure gradient at the position of collector is decreasing constantly with the reduction of the height of collector. When the height of collector is 240 mm, the static pressure coefficient and static pressure gradient close to the collector becomes negative. For the small nozzle, the area of the collector is much larger than that of the nozzle so that the velocity of airflow at the collector decreases, which contributes to a positive value of the local static pressure coefficient and static pressure gradient.
ZHU Jianyue , WANG Yigang , YANG Zhigang , LI Qiliang , CHEN Yu
2017, 45(10):1512-1521. DOI: 10.11908/j.issn.0253-374x.2017.10.014 CSTR:
Abstract:The influence of a bogie fairing on the aerodynamic and aeroacoustic behaviour of flow past a simplified highspeed train bogie located in a bogie cavity at a scale of 1∶10 was studied using a twostage hybrid method comprising computational fluid dynamics and acoustic analogy. The nearfield unsteady flow was obtained by solving the NavierStokes equations numerically with the delayed detachededdy model and the results are used to calculate the farfield noise through a noise prediction code based on the convective Ffowcs WilliamsHawkings method. It is found that due to the surface shape discontinuity in the bogie cavity along the carbody side and bottom walls, a highly turbulent flow is generated within the bogie cavity. The vortices formed behind the upstream geometries are convected downstream and impinge on the downstream bodies, generating a highly turbulent wake behind the bogie. When the fairing is mounted around the bogie cavity, the interaction between the flow and the bogie cavity is reduced. The results show that the bogie fairing is effective in reducing the noise generated in most of the frequency range for the current model case based on predictions of the noise radiated to the trackside using a permeable data surface close to the bogie and parallel to the carbody side wall.
CHEN Chunfeng , ZHU Weilin , FU Xiaowei , XU Donghao , ZHANG Bocheng
2017, 45(10):1522-1530. DOI: 10.11908/j.issn.0253-374x.2017.10.015 CSTR:
Abstract:To fully recovery provenance of Mingyuefeng Formation of Well W6 in upper Paleocene in Jiaojiang Sag and probe research methods for provenance analysis applied to sea area, this research used detrital framework grains, heavy minerals and detrital zircon UPb dating for the comprehensive provenance analysis. The result shows that the Lower Mingyuefeng Formation(LMF) and Upper Mingyuefeng Formation(UMF) have entirely different provenance in the east part of Jiaojiang Sag. The main source of LMF is from Haijiao Uplift located to the east of the sag and is mainly acid intrusive rocks formed in transitional arcdissected arc with zircon UPb age ranging from 183 to 209 Ma. In addition, there is a small amount of contribution of the metamorphic and Mesozoic igneous in other age range. The main source of UMF in Jiaojiang Sag is possibly from Zhemin Uplift to the west of the sag with acid volcanic rocks and intrusive rocks formed in transitional arc with the zircon age about 106~116 Ma. It has nearly the same source rocks with the adjacent areas whose provenance area is located in the western Minzhe Uplift. This conclusion is also supported by the depositional system evolution. The change of provenance is the resulted from the tectonic and deposition environment change in late Paleocene, which has a great impact on the cap rock and the sealing capability to the oil and gas bearing in this area.
KE Baogui , ZHANG Liming , WANG Wei , XU Jun , ZHANG Chuanyin , DANG Yamin
2017, 45(10):1531-1538. DOI: 10.11908/j.issn.0253-374x.2017.10.016 CSTR:
Abstract:Based on three and a half years of satellite altimetric GDR data of cryosat2, the deflection of the vertical grid were obtained by using sea surface height gradient data and the least square collocation method in coastal region of China. The inverse Vening Meinesz formula and the removerestore technique were adopted to get sea gravity anomaly in the interested region. After fusion with the shipborne gravity data,the precision of the constructed gravity anomaly was found to be from 2.75 mgal to 5.38 mgal and the mean value was from -0.21 mgal to 0.45 mgal. Compared with DTU13 gravity field model, the maximum mean value improvement was 12.98 mgal and standard deviation improvement was 3.4 mgal. Compared with the Sandwell V23.1 gravity field model, the maximum mean value improvement was 13.58 mgal and standard deviation improvement was 1.09 mgal.
MA Junmei , YANG Yuting , GU Guiding , XU Chenglong
2017, 45(10):1539-1548. DOI: 10.11908/j.issn.0253-374x.2017.10.017 CSTR:
Abstract:This paper researched the estimation of price and Greeks of European options on the two kinds of stochastic volatility models. Rejection sampling technique was discussed in detail to improve the sampling efficiency based on the exact simulation algorithm of stochastic volatility models of Broadie and Kaya. Then conditional Monte Carlo and antithetic variable techniques were used to reduce the variance of Monte Carlo simulation. The numerical results show that the combination of exact simulation and conditional Monte Carlo method can get unbiased estimation and smaller variance, compared with the crude Monte Carlo and Euler discretization. The algorithm proposed in this paper can also be used to solve the calculation problems of other more sophisticated products, such as the estimation of the price and Greeks for barrier options and basket options.
WU Yanhui , REN Weili , WU Gaosheng , LIU Zhongneng , YU Qiang
2017, 45(10):1549-1554. DOI: 10.11908/j.issn.0253-374x.2017.10.018 CSTR:
Abstract:Thermodynamics of aldol condensation of formaldehyde and isobutyraldehyde (IBD) were studied. With the application of Joback and Yoneda (ABWY) group contribution methods and some other empirical formulas, the basic thermodynamic properties such as Hg,298, Sg,298, Cp of the main product of 2,2dimethyl3 hydroxypropionaldehyde (HPA), the byproducts of neopentylglycol (NPG), hydroxypivalaldehyde (1115 acetate), isobutyl isobutyrate and other substances were calculated. Then, the Hr,Gr, Kp of the main and side reactions were derived. The calculated thermodynamic properties agree well with available literature values, which means that the estimation is reliable. The calculated results show that the main and side reactions are exothermic and can happen spontaneously. Relative low temperature is good for the main reaction, because the absolute enthalpy of this main reaction is lower than that of the side reactions. NPG, 1115 ester, and isobutyl isobutyrate are the main byproducts. The conversion rate of IBD would decrease with the increase of temperature and n(IBD)∶n(HCHO). When the ratio of n(IBD) to n(HCHO) is 0.9, IBD conversion rate can reach 99%. The calculated conversion rates at different ratios of n(IBD) to n(HCHO) agree well with experimental data. The thermodynamic analysis would provide basis for the optimization of industrial HPA preparation.
YOU Jianxin , CAI Wenjun , YOU Xiaoyue
2017, 45(10):1555-1560. DOI: 10.11908/j.issn.0253-374x.2017.10.019 CSTR:
Abstract:This paper proposed a customer claims model by improving the traditional FMEA model using the AHP method and fuzzy TOPSIS. Failure modes of claimed products were evaluated and ranked based on four criteria, while critical failures should be solved with priority to reduce business loss. A case study on auto instruments of company C was used to illustrate the effectiveness of the proposed model. The results show that the most serious failure mode is inoperative instruments caused by circuit board damage or install error, which should be improved first to avoid customer claims. The case results are consistent with the company’s expectation and show the feasibility and practicability of the proposed method.
WANG Jing , ZENG Shajie , JU Juan
2017, 45(10):1561-1568. DOI: 10.11908/j.issn.0253-374x.2017.10.020 CSTR:
Abstract:Combining the study of resourceconstrained projectscheduling problem with the demand of construction schedule management in real projects, this paper integrates a hybrid algorithm with generalized precedence relations (GPRs) scheduling model, and then proposes better solutions for resourceconstrained schedule management. The hybrid algorithm presents crossover and mutation operations from differential evolution (DE) with artificial bee colony (ABC) to balance exploration and exploitation phases of the optimization process. Furthermore, the proposed model applies a serial method with generalized precedence relations to reflect individualvector priorities into the task schedule to calculate project duration. In order to generalize the use of most realworld construction projects, the resourceconstrained schedule management contains some methods by calculating critical paths, applying resource leveling of noncritical tasks, using correlation analysis to tradeoffs between time and cost of critical tasks. In the eclipse environment of Java programming language, it could obtain stable and accurate results, which project managers may use to make optimal decisions by resource constrained schedule, resource allocation, the optimized schemes of resources and duration.
TANG Wenzhe , LEI Zhen , SUN Hongxin , YOU Richun
2017, 45(10):1569. DOI: 10.11908/j.issn.0253-374x.2017.10.021 CSTR:
Abstract:In international projects, firms need to cope with the challenges posed by institutional differences. Existing studies focus on the perspective of risk management and propose corresponding strategies to deal with the fact that institutional differences can cause great trouble to the implementation of international projects. However, it has not been systematically studied whether influences of different types of institutional differences on different implementation issues are of similar degree. Based on the data of the international projects of Chinese construction firms collected by questionnaire and interviews, the influences of different institutional differences on project implementation are analyzed. The results show that the influence of technical standards difference on design, procurement and construction issues is the most prominent. Cultural difference also has some effects on project implementation. Difference in laws and regulations, however, has no statistically significant influence on project implementation issues. Chinese construction firms should pay more attention to the standards and cultural factors when dealing with institutional differences.
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