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Village classification is an important foundation for preparing village planning and formulating development strategies. This study takes a typical plateau mountain area-Yulong County, Yunnan Province as the research object. First, the analytical hierarchy process is used to build a “three evaluations” (ecological sensitivity, development potential, and construction suitability)indicator system. Second, spatial correlation analysis of the “three evaluations” was carried out to obtain the initial village classification results. Finally, the state space method was used to calculate the village bearing capacity, which could be used to correct the initial village classification. Thus, the final village classification could be obtained. The results show that a significant plateau mountain space distribution of heterogeneity was shown in the villages of the research area, and the spatial autocorrelation coefficients of the “three evaluations” were 0.343, 0.253, and 0.110, respectively; more than 60% of the villages were in a bearing state and the higher bearing capacity was concentrated in the southeast, northwest, and central regions of the research area. After the comprehensive carrying capacity was calculated and corrected, the special protection category accounted for 23%, the suburban integration category accounted for 4%, the relocation and withdrawal category accounted for 15%, the agglomeration and promotion category accounted for 40%, and the temporary unclear category accounted for 18%. For different types of villages, the layout optimization strategy should be proposed according to the carrying capacity calculation results. The results of this research can provide a reference and basis for the formulation of township(town)-level territorial spatial planning and the implementation of “multi-planning” practical village planning. [ABSTRACT FROM AUTHOR]

Karst caves should be avoided as far as possible during pile foundation construction, but sometimes it is unavoidable. Therefore, research on the bearing characteristics of pile foundations in karst areas is a problem that must be faced. The current status of research on the bearing characteristics of pile foundations in karst areas from three aspects: theoretical research, physical experiments, and numerical simulation was analyzed. The following conclusion was drawn. The existing bearing capacity calculation formulas have insufficient consideration of influencing factors, and subsequent theoretical research should consider the derivation of single pile ultimate bearing capacity calculation formulas under the synergistic influence of multiple factors. The variables in physical model tests are relatively single, and the influence of water on the bearing characteristics of pile foundations is often ignored during the testing process. Subsequent research should focus on the synergistic effect of groundwater and multiple factors. There are few in-situ experiments conducted, and the accuracy of the data obtained through detection needs to be improved. In the future, more in-situ experiments and in-site damage experiments should be carried out to obtain more comprehensive experimental data on the bearing characteristics of pile foundations. Most of the cave models are built with standard size in numerical simulation, which is inconsistent with the three-dimensional geometric size of the actual stratum cave. The establishment of a more realistic Geometric modeling of the cave is a key development direction in the future. [ABSTRACT FROM AUTHOR]

The section K0 +785 -K0 +988 on the north shore of the Dalian Bay immersed tunnel, which is higher than the original seabed surface, is susceptible to ship collision risks and requires anti-collision measures. Taking into account factors such as construction difficulty, environmental protection, and cost, a permeable gravity pier foundation composed of circular caissons, column piles, and cast-in-place piers was proposed as the anti-collision structure, while meeting the requirements of the construction period. Combined with the structural form and main loads of the anti-collision pier, the overall stability of the anti-collision pier structure and the bearing capacity of the column piles were analyzed and calculated using finite element method and specification method. The results show that the permeable gravity pier anti-collision structure can meet the requirements of engineering use in all aspects, and can provide design reference for the construction of similar structures in the future. [ABSTRACT FROM AUTHOR]

Aiming at the problem that it is difficult to ensure the comprehensive improvement of the load capacity and transmission accuracy of the RV reducer during the modification process of the RV reducer, and most of the research on the modification is the single-objective modification. The optimization method with the goal of reducer carrying capacity and backlash was proposed based on the RV,and dynamic experiments were conducted on the modified RV reducer using a comprehensive performance testing platform. Firstly, considering the modified tooth profile equation of the cycloid wheel and the specific parameters of the RV reducer required for the modification, the contact force generated by the standard cycloid wheel was analyzed. Then, according to the position of the maximum contact force, the calculation method of the power of the cycloid gear teeth was obtained. The number of teeth meshing at the same time was judged by comparing the initial meshing gap between the cycloid gear and the pin teeth and the deformation of the cycloid gear and the pin gear. MATLAB iterative calculation method was used to calculate the accurate maximum contact force, and the Hertz formula was used to calculate the leading contact force. Finally, the influence of different modification methods on the return difference was analyzed, and a multi-objective optimization model was established. The improved NSGA-Ⅱ algorithm gamultiobj genetic algorithm was used for optimization, and the optimal modification amount under the minimum fitness was obtained by solving the solution. To verify the accuracy of the modification method, a dynamic experiment was conducted on the modified RV reducer using a comprehensive performance testing platform. The research results show that after optimization, the maximum contact stress between cycloid gear teeth is respectively reduced by 11% and 13%, comparing with median and displacement modification. The optimized return difference is 0.013′, compared with both the equidistant change and the displacement modification, it has been improved. The multi-objective modification with the load capacity and backlash as the optimization target can better solve the problem of improving the comprehensive performance of the RV reducer. [ABSTRACT FROM AUTHOR]

After more than 30 years of development, the foundation calculation system has been updated with the updating of codes and standards. Though the latest version of codes and standards have been released, the corresponding software has not been updated. At the same time, with the expansion of business, the required software should be able to be used in different fields, adaptable to both domestic and foreign codes and standards, and be used more conveniently and efficiently. Therefore, the Foundation Calculation System version 5.0 (FOCAS 5.0) has been developed. The pre-post processing of the new version of the software is compiled with JavaScript. The pre-processing input is convenient, with the function of checking, while the postprocessing displays results in modules and can generate editable calculation sheet. The kernel is developed in the C language, which has kept the calculation modules of 2008 edition, and also expanded the corresponding calculation method. In the module of foundation bearing capacity and slope stability, more calculation methods have been included, which can adapt to codes and standards in different fields and of many countries. It is the richest calculation methods in similar types of software. The new version of the software is a reliable and efficient calculation tool, and also provides reference for similar domestic software. [ABSTRACT FROM AUTHOR]

In order to reveal the mechanism of pile-side grouting reinforcement of existing bridge pile foundations in silty clay stratum, the relationship between grouting pressure and water-cement ratio on the reinforcement effect of pile-side soil was investigated through model tests, and numerical simulations were used to obtain the law of pile-side grouting on the bearing characteristics of existing pile foundations. The research results show that the cement slurry is squeezed and split reinforced in the silty clay, and the diffusion pattern shows linear and radial. The grouting silty clay reinforcement effect is positively related to the grouting pressure, and it shows the trend of increasing and then decreasing with the increase of water-cement ratio. Pile side grouting reinforcement can effectively improve the lateral friction resistance within the reinforcement area, and the deep part of the pile foundation has more obvious improvement of lateral friction resistance compared with the shallow part. [ABSTRACT FROM AUTHOR]

In order to explore the reinforcement effect of wrapped gravel pile on silty clay foundation, based on model test and numerical simulation method, the bearing capacity characteristics of wrapped gravel pile and traditional gravel pile composite foundation were studied, and the effects of gravel modulus, gravel internal friction angle and geogrid stiffness on the bearing capacity and deformation of wrapped gravel pile composite foundation were analyzed. The results show that when the load of traditional gravel pile composite foundation is less than 20 kPa, the settlement increase is not obvious. When the load is greater than 30 kPa, the settlement increases rapidly and the composite foundation is unstable and damaged. Within a certain particle size range, under the same grading, the larger the particle size of the gravel, the smaller the overall deformation of the gravel pile and the higher the bearing capacity. The gravel modulus of wrapped gravel pile has obvious effect on the settlement of composite foundation under high stress. When the pile-soil modulus ratio is greater than 30, its influence on the settlement of composite foundation gradually weakens. Increasing the internal friction angle of gravel can effectively increase the pile-soil stress ratio and improve the stress transfer efficiency of the pile. With the increase of internal friction angle, the settlement of composite foundation decreases gradually, and its effect is more obvious at high load level. The wrapping of geogrid can reduce the settlement of composite foundation, but the influence is limited. When J > 1 000 kN/ m, the influence on the settlement is gradually weakened. [ABSTRACT FROM AUTHOR]

aboratory tests were carried out on the silt solidified by the granulated blast furnace slag (GGBS) alkali-activated by hydrated lime and MgO powder. The optimal mixing amount of hydrated lime and MgO powder used as the alkali activator of GGBS was determined. The bearing capacity of the silt solidified by the GGBS alkali-activated by hydrated lime was studied by using field test. The research shows that the silt solidified by the GGBS alkali-activated by 15% MgO powder and 6% hydrated lime can be used as bridge abutment backfill materials. Considering the economy and reinforcement effect, the silt solidified by the GGBS alkali-activated by 6% hydrated lime can be used as the backfill material of abutment of road-bridge transition section in practice. The present research can be used for controlling differential settlement of road-bridge transition section of expressway. [ABSTRACT FROM AUTHOR]

In order to evaluate the structural performance and working state of the newly built prefabricated bridge, the single girder static load test, the whole bridge static and dynamic load test and the finite element simulation analysis were carried out on the 40 m T beam section of the Jiulinggang bridge of suide expressway. Through the static load test, the strain and deflection of the control section of the single beam and the bridge stage were tested, and the finite element calculation results were compared and analyzed. The natural vibration characteristics of the bridge, the dynamic effect and the impact effect under different driving speeds were obtained by the pulsation test and the driving test. The research results show that, the structural strain and deflection calibration coefficients of single girder and full bridge under static load all meet the requirements of the specification, and the relative residual strain and displacement after unloading are far less than 20% of the specification, and the structural bearing capacity is good. The deflection, strain value and load lateral distribution coefficient of the side beams at all levels of loading are all larger than those of the middle beams, and the overall deformation and stress distribution are relatively uniform, and the torsional stiffness and strength of the structure have a certain safety reserve. The measured damping ratio of the pulsation test is 1. 139%, which is less than 5% specified in the specification, with good dynamic characteristics and good energy dissipation performance during the vibration of the structural system. In the driving test, with the increase of the vehicle speed, the dynamic effect of the structure is more obvious, and the dynamic deflection, dynamic strain and impact coefficient have a tendency to increase obviously, the measured impact coefficients range from 0. 065 to 0. 133, indicating that the bridge deck has good flatness. [ABSTRACT FROM AUTHOR]

Black soil region can serve as the main production area of commodity grain in Northeast China. There is the soil quality decline of cultivated land in recent years, such as the thinner and harder land. Among them, the efficient return of agricultural waste as a carbon source can be an important way to improve soil quality. However, it is still lacking in the regional, agricultural production system model using the regulation of the carbon cycle between plant and animal, in order to promote the return of carbon to the field for the recovery of black land fertility. This study aims to improve the soil organic matter content of black land for recovery. The research object was selected as Qiqihar City located in the hinterland of Songnen Plain in Heilongjiang Province of China. The soil carbon budget of each county was calculated to compare the difference between the soil carbon input and output of different crops. The agricultural carbon balance model was established for plant and animal husbandry using multi-objective linear programming. The least carbon emission and the highest economic benefit were taken as the main targets, while the efficient use of agricultural and waste resources was the secondary target. As such, the balance between soil carbon emission and carbon input was determined, according to the situation of each county. The results showed that the adjustment plan in each county was optimized to reduce the rice planting area, while increasing the cow farming scale and maize planting area with high biomass. There was no decrease in the soil carbon pool of farmland after the full utilization of the waste of cultivation and breeding industry. However, the scale of plant and animal husbandry at the county level should be adjusted, according to the local conditions. Taking Nehe City with a large soil carbon deficit as an example, the maize planting area increased by 46%, while the scale of beef breeding should be reduced by 63%, and the scale of cows, pigs, sheep and poultry breeding increased by 85%, 54%, 76%, and 71%, respectively, in order to balance the carbon input and agricultural economic benefits. Take Longjiang County with a small soil carbon deficit as an example, the rice planting area, and the beef and pigs breeding industry should be reduced, while the corn and soybean planting area increased, and the scale of cows, pigs, and poultry also increased. The organic materials returned to the field were replaced by 33%-49% of the fertilizer nitrogen input after the planting and breeding scale, particularly for the higher soil quality and the soil nitrogen carrying capacity. Moreover, the soil nitrogen-carrying capacity of the three main crops showed an increasing trend, except for the maize planting in Kedong and Keshan County. The agricultural “carbon balance” development model can be expected to serve as the scientific basis for the efficient utilization of agricultural waste resources. The finding can also provide a strong reference to realize the “double carbon” strategy in the black soil area. [ABSTRACT FROM AUTHOR]

Umbilical terminal head is the key hardware equipment of underwater umbilical, which bears complex and harsh loads in deep sea environment, and puts forward higher requirements on the structural capacity of connection system. The deep water umbilical terminal head used in a gas field in the South China Sea was taken as the research object. Based on International Organization for Standardization(ISO)and Der Norske Veritas(DNV) related standards, a finite element model was established for the outer structural components of the umbilical cable terminal according to the elastic-plastic and pure elastic stress analysis methods, and the numerical analysis was carried out. The axial load capacity, shear load capacity, bending moment capacity and torque capacity under production conditions were obtained, and the influence of different lifting methods on the bearing capacity of the deep water umbilical termination head was analyzed. The analysis results show that the bearing capacity calculated under normal production conditions all meet the relevant standard evaluation indicators. Different lifting methods have different effects on the bearing capacity of the deep water umbilical termination head. Compared with the two-point lifting scheme, the four-point lifting scheme is less prone to stress concentration and meets the safety strength requirements. The research results can provide theoretical basis and technical reference for the design and field engineering application of umbilical terminals head. [ABSTRACT FROM AUTHOR]

Offshore floating wind power has developed rapidly in recent years, and the high construction cost is the key factor hindering its development. Drag embedded anchor has become a choice of floating wind power anchor foundation because of its low manufacturing and installation cost. The penetration depth and bearing capacity of drag anchors in clay were calculated by using empirical chart method, theoretical calculation method and finite element method. The results show that the empirical method provided by the manufacturer has low calculation accuracy and is suitable for the initial selection of drag anchor. The results of theoretical calculation method is sensitive to the soil parameters. The finite element analysis shows that the penetration depth of the drag anchor is the key factor to control the bearing capacity. According to the above calculation results, the design process of the drag anchor was proposed. It should be noted that the calculation parameters need to be carefully selected according to the process to ensure the safety and reliability of the project. [ABSTRACT FROM AUTHOR]

As an important connection mode of prefabricated construction, the mechanical properties of grouting sleeve have great influence on the structure safety. As the main mechanical indexes of joint connectors, the ultimate bearing capacity and bond strength are affected by grouting material strength, anchorage length of rebar, eccentricity of specimens, construction disturbance, high temperature, cycle of freezing and thawing, corrosion and other factors. Starting from the components of the grouting sleeve, the grouting material, the sleeve and the connecting steel bar, the influence of different factors on the mechanical properties of specimens was summarized, the existing strength calculation formulas was summarized under different influencing factors. According to the current development situation, the future research direction was put forward, a foundation for the further development of prefabricated buildings was layed. [ABSTRACT FROM AUTHOR]

Hat-shaped steel members are widely used in solar greenhouses, due to their low cost, fast construction, and high material efficiency. This study aims to determine the ultimate bearing capacity of a solar greenhouse with the hat-shaped steel under snow loads. The typical solar greenhouse with an 8 m span and 3.8 m ridge height was selected as the research object. The finite element method (FEM) under ANSYS software was used to analyze the instability mechanism and failure modal of the structure under snow loads (uniform and non-uniform snow loads). An investigation was made to clarify the effects of the longitudinal tie bars, initial geometric imperfections, and sectional dimensions on the ultimate bearing capacity of the structure under non-uniform snow loads. Both the material and geometrical nonlinearity were considered in the finite element model. A bilinear kinematic hardening model was adopted for the steel with a yield strength of 235 MPa, Young’s modulus of 206 GPa, and Poisson’s ratio of 0.3. The geometrical nonlinearity was activated using the ‘NLGEOM’ option. To consider the local buckling, the greenhouse skeletons were then modeled with the Shell181 element suitable for the large strains and rotations. Fixed hinge supports were used for both ends of the skeleton. An arc-length method was utilized to trace the nonlinear load-displacement curve, in order to calculate the ultimate bearing capacity of the structure under snow loads. The ultimate bearing capacity of the solar greenhouse with the hat-shaped steel was slightly higher than that of the hollow rectangular section under the same conditions of net section area, upper flange width, web depth, and wall thickness. The solar greenhouse was more sensitive to the non-uniform snow loads, compared with the uniform ones. The ultimate bearing capacity of the hat-shaped steel solar greenhouse under non-uniform snow loads was about 28% of that under uniform snow loads. Therefore, some suggestions were presented for the non-uniform snow loads in the design stage of the solar greenhouse structure. The roof ridge and north roof end were dangerous sections under non-uniform snow loads, which firstly entered the full section yield state. The longitudinal tie bars were expected to effectively improve the ultimate bearing capacity of the greenhouse structure. The ultimate bearing capacity of the structure with the longitudinal tie bars was about 1.25 times that without tie bars. The ultimate bearing capacity was only reduced by 2%, when the initial geometric imperfections amplitude increased from 5 to 20 mm. It infers that the solar greenhouse was not sensitive to the initial geometric imperfection. The cross-section size of a hat-shaped steel was recommended that the ratio of the upper flange width to the lip width, the upper flange width to the lower flange width, and the web depth to the lower flange width were about 4.17, 3.33, and 4.67, respectively, while, the ratio of the web depth to the lip width, and the lower flange width to lip width were less than 9.25 and 1.7, respectively. These findings can provide a strong reference for the solar greenhouse with the open cold-formed thin-walled steel under snow loads. [ABSTRACT FROM AUTHOR]

The construction of the comprehensive pipe corridor in Xiong’an New Area utilizes the automatic installation of gallery above gallery technology. The subsidence and the bearing capacity of the subcrust under front leg of self-advance large-tonnage installation machine are important to the design of the machine as well as the safe installation. In this paper, the JXSG-6 segment of Jing-Xiong interurban railway in Xiong’an New Area was selected as the field test site to conduct the numerical modeling and the plate loading test to the subcrust under the front leg of the installation machine. Numerical models were developed to investigate the subsidence and stress distribution of the soil under different plate widths and subcrust thickness. The loading test had ten levels of loading and 40 kPa for each level. The results show that: the subsidence of the soil decreases 52.5% when the plate width increases from 1m to 5. The subcrust thickness is optimized at 20 m considering the safety and leveling. The subsidence for each loading stage is around 0.43-0.78 mm, which first decreases, then stabilizes and increases again. The total subsidence after completion of the test is 5.72 mm. At the designed pressure of the front leg, the subsidence is only 1.98 mm. The road surface around the testing area, the sand below the loading plate and the subcrust show good integrity after the loading test. No visible subsidence or any cracks can be observed. The stiffness coefficient of subcrust foundation is calculated as 69.93 MPa/m and the modulus is 58.1 MPa. It can be concluded that the subcrust under the front leg of the installation machine has adequate bearing capacity for the construction of the comprehensive pipe corridor using the pipe gallery installation machine. [ABSTRACT FROM AUTHOR]

Aiming at the problem of inaccurate prediction results of bearing capacity, a bearing capacity prediction method of reinforced concrete members based on immune algorithm is proposed. The bearing capacity prediction objective function of reinforced concrete members is established by static load test, and the ultimate bearing capacity of members is obtained by solving the objective function by immune algorithm. The experimental results show that the prediction result of the bearing capacity prediction method of reinforced concrete members based on immune algorithm is 215 3 kN, which proves the effectiveness of this method. [ABSTRACT FROM AUTHOR]

The self-balanced test pile method is gradually popularized due to its convenience and economy. However, few studies were focused on the conversion coefficient involved in the process of converting this method into the static load-displacement curve. Because the settlement on the pile top is affected by soil continuity, the displacement difference on the pile top of the self-balanced test pile and the static load pile were analyzed using the Mindlin′s formula based on the comparative study of the self-balanced test pile method and the traditional vertical compression static load test method of single pile. An equivalent conversion method to determine the bearing capacity of self-balanced test pile was proposed in order to improve the empirical formula. The rationality of the improved method was verified by indoor simulation test as well as pile foundation engineering test of a super high-rise building in Shenyang. It is found that the self-balance conversion method taking the soil continuity in to account can significantly reduced the fitting error of the load-displacement curve. [ABSTRACT FROM AUTHOR]

In order to study the effect of the replacement rate of recycled coarse aggregate, length-diameter ratio and diameter-thickness ratio on the axial compressive bearing capacity of middle long columns of recycled aggregate concrete with ferronickel slag filled steel tubes (RACFNSFST), the monotonic loading tests were carried out on eight RACFNSFST under axial compression. By comparing the calculation method of axial compressive capacity recommended by the domestic and foreign common concrete-filled steel tube codes, the prediction formula of axial compressive capacity is fitted by regression and compared with the test results. The results show that local buckling occurs at both ends of the medium and long column, which is the failure mode of material, and the long column is the failure mode of whole instability. The medium and long columns with the same reclaimed coarse aggregate substitution rate and section size have better bearing capacity and slower deflection growth than that of the long columns. With the increase of diameter-thickness ratio, the bearing capacity and ductility are reduced, and the hoop effect of steel tube on recycled concrete is obvious. The fitting formula is simple and practical, and it is in good agreement with the measured value. [ABSTRACT FROM AUTHOR]

Based on the model test of the inverted trapezoidal reinforced soil retaining wall under the existing in⁃ door strip foundation, the three dimensional numerical model of the reinforced soil retaining wall was established by FLAC3D finite difference software, and the influence of the foundation offset distance D on the ultimate bearing capacity of the retaining wall, the panel horizontal displacement, tensile stress distribution of reinforcement and potential fracture surface was discussed. The research results show that the ultimate bearing capacity of the foundation first increases and then decreases with the increase of the foundation offset distance D. Through a comprehensive analysis of the ultimate bearing capacity of the foundation, the bearing capacity corresponding to the settlement of 0.1b(b is the width of the foundation) and the final settlement of the foundation, the best offset distance of the foundation is D=0.45H(H is the wall height). When D/H≤0.45,the maximum horizontal displacement of the retaining wall panel appears at the top, when D/H>0.45H,the maximum horizontal displacement of the retaining wall panel appears in the middle of the retaining wall about 0.4H from the toe of the wall. With the increase of D/H, the peak tensile stress of the reinforcement gradually shifts to the inside of the retaining wall, and the distribution is nonlinear in the direction of the length of the reinforcement. The potential rupture surface of the retaining wall is significantly affected by the offset distance D of the foundation, and the position of the rupture surface is overall offset to the load direction, and can be represented by an exponential curve. [ABSTRACT FROM AUTHOR]

Based on rhombic and honeycomb hexagonal non pneumatic tires, a rhombic honeycomb rhombic composite tire was proposed. The load-carrying capacity, grounding performance, fatigue life and rolling state of 10 kinds of composite tires with different proportion of honeycomb and rhombic were analyzed by using finite element simulation software. The simulation results of different tire structures were compared. The results show that the performance of the tire is better when the ratio of rhombic structure to honeycomb structure is even, and when the ratio of rhombic structure to honeycomb structure is 1:4, the comprehensive performance of the tire is the best. [ABSTRACT FROM AUTHOR]

In order to study the influence of joint stiffness on the stability of tubular truss arch, a variable stiffness spring model under reciprocating load was used to replace shell element to consider the semi-rigidity of joints on the basis of the consistency of hysteretic performance of spring element and shell element. The stiffness equation of the spring model was determined by the skeleton curve of the node shell element model under reciprocating load. Taking a tube truss arch with a span of 50 m and a span of 0. 29 as an example, the stability of the joint domain spring model and the common model was analyzed by using material and geometric nonlinear finite element method. The results show that “static instability mode” is the most unfavorable initial defect form of space tube truss arch. The influence degree of joint stiffness on the bearing capacity of tubular truss arch is related to the size, distribution form and load range of initial defects. [ABSTRACT FROM AUTHOR]

With the great development of urban underground space, both the buried depth of the foundation and the buoyancy of the groundwater continue to increase, which may easily cause the foundation pit to float during the construction process or even affect the normal use of the underground structure. Due to the small disturbance to the rock and soil around the pile during construction, the anti-uplift pile has advantages over simple technology, convenient construction, and good anti-floating effect. That is why it is widely used in anti-floating projects. At present, the mechanical properties, bearing capacity and deformation characteristics of uplift piles are the research hotspots of uplift piles in anti-floating engineering at this stage. The action mechanism of the uplift pile, common failure forms and ultimate bearing capacity were mainly summarized and analyzed, some problems of uplift pile in anti-floating engineering were put forward, which provides a new idea for the future development of uplift pile in the field of anti-floating of underground structure. [ABSTRACT FROM AUTHOR]

To improve the bearing capacity of offshore wind turbine foundation, a pile-bucket composite foundation with bucket foundation and steel piles was designed. Based on the limit equilibrium method, the theoretical formula of horizontal bearing capacity of pile-bucket composite foundation was proposed with considering different pile numbers. The finite element analysis model was established to analyze the bearing capacity of pile-bucket composite foundation with different pile numbers, pile diameters and arrangements. The results show that the ultimate bearing capacity of pile-bucket composite foundation can be effectively improved for the same steel amounts of foundation. Compared with single bucket foundation, the bearing capacity of bucket foundation with 1 pile is increased by 44.27%, and the bearing capacity of bucket foundation with 3 piles is increased by 35.76%, while the bearing capacity of bucket foundation with 4 piles is increased by 34.73%. Obvious wedge-shaped equilibrium plastic strain is appeared in the soil foundation of the passive area. The more obvious the equilibrium plastic strain is, the higher the load sharing ratio of foundation soil is, and the higher the bearing capacity of foundation is. The high stress area of foundation is mainly concentrated in the top cover of foundation. [ABSTRACT FROM AUTHOR]

To investigate the reinforcement measures of solar greenhouse structure under extreme wind and snow disasters, the single frame model of solar greenhouse was established by ANSYS finite element analysis software with consideration of material nonlinearity, large geometric deformation and structural nonlinearity conditions. The whole processes of instability and failure for the solar greenhouse structure under four load conditions of wind, snow, wind-led blizzard and snow-led blizzard were respectively simulated. According to the instability mode and load-displacement relationship curve of the structure, the temporary reinforcement methods were proposed. The results show that the wind and snow resistance of the solar greenhouse is significantly improved after temporary reinforcement. The wind load bearing capacity is increased by 154%-300%,and the snow load bearing capacity is increased by 11%-129%. The wind-led blizzard bearing capacity is increased by 245%-273%, and the snow-led blizzard bearing capacity is increased by 203%-264%. [ABSTRACT FROM AUTHOR]