Tianjin Ganghang Installation Engineering (China)

Diffractive lens (DLs) computational imaging promises lightweight infrared imaging. However, it is still challenging to accurately obtain the degradation of DLs computational imaging systems to achieve high-quality imaging. Degradation estimation methods based on image-to-image are the most feasible way, but existing methods face the problem of low accuracy for severe degradation estimation. In this paper, we proposed a severe degradation estimation framework based on KernelNet, and realized the improvement of the accuracy of severe degenerate estimation by more than 1.13 dB. Furthermore, DyUnet, an image restoration network, was proposed, which is based on dynamic convolution. The results of the mid-wave diffractive lens infrared computational imaging system indicated that our method achieved high-quality imaging results comparable to the conventional one, while the number of optical elements was reduced from 7 to 2, and the weight was reduced by 50%.

Cold-recycling technology with foamed asphalt is used widely because it has the incomparable advantages of environmental protection and resource conservation. In this study, cold-recycled mixtures with foamed asphalt were prepared with different gradation types, mixing water contents, and curing times to study the distribution characteristics of residual moisture. An optimum foaming water content of 2.5% and foaming temperature of 165°C were determined for producing the foamed asphalt that was used for the cold-recycled asphalt mixtures. Hyperspectral imaging tests and spectral processing technology were used to obtain the image information and spectral information of residual moisture from 44 specimens; the moisture content of all specimens ranged from 0.25% to 4.70%. Pseudocolor-coding technology was utilized to realize visualization of moisture distribution. In addition, the residual moisture content prediction model was established based on the partial least-squares regression (PLSR) model. Correlations of the residual moisture distribution characteristics and moisture damage resistance evaluation indicators were developed. The residual moisture distribution characteristics and moisture damage resistance are affected significantly by aggregate gradations, mixed water content, and curing time. After 3 days of curing, the strength of the recycled mixture tends to be stable, and the moisture damage resistance can reach the specification requirements, and is suitable for open traffic. It was confirmed that there is a certain correlation between the internal residual moisture content value distribution range and the moisture damage resistance of the cold-recycled mixtures with foamed asphalt. This study could contribute to a better application of cold-recycled asphalt pavement for environmental protection and carbon stabilization.

The monitoring of subsea ground settlement and pore water pressure is key indexes for evaluating the safety of offshore channel engineering cases. The monitoring of settlement and pore water pressure for onshore cases is easy to proposed, and lots of instruments can meet the need. While for offshore engineering cases, the monitoring instruments should survive under extreme bad environment. This paper analyzed several monitoring instruments based on a 12.5 deep offshore channel engineering located at Nanjing city. A suit of instrument was final chosen after comparison.

Based on a high fill subgrade in Indonesia, this paper uses finite element software to simulate the settlement deformation characteristics of high fill subgrade under the condition of reinforced cushion. The calculation results show that although the existence of the reinforced cushion cannot significantly reduce the foundation settlement, it has obvious effect in ensuring the stability of the shoulder. The stability safety factor of the 9m high roadbed with the reinforced cushion layer increases by about 0.2. It is suggested that the reinforced soil cushion can be used as a reinforcement measure to ensure the stability of the shoulder when high-fill roadbed construction is carried out on soft soil foundation.

The depth, arrangement mode and the loading mode of plastic vertical drainage (pvd) have great influence on the reinforcement effect. An arrangement mode of vacuum preloading to reduce the impact was put forward. The combination of different depth of pvd and loading modes are used to analyse the effect of vacuum preloading treatment and its influence range. The calculations show that the deformation and the influence distance are smaller by using the 40kPa vacuum loading and 41kPa surcharge load preloading. Reducing the depth of the pvd and vacuum combined surcharge preloading can weaken the influence to the existing highway.

According to the depth of plastic vertical drainage (pvd), the arrangement mode and the loading mode to analyze the influence of Vacuum preloading near the existing road. An arrangement mode of vacuum preloading to reduce the impact was put forward. The combination of different depth of pvd and loading modes are used to analyze the effect of vacuum preloading treatment and its influence range. The calculations show that the deformation and the influence distance are smaller by using the 40kPa vacuum loading and 41kPa surcharge load preloading. Reducing the depth of the pvd and vacuum combined surcharge preloading can weaken the influence to the existing highway.

The vacuum preloading will produce an effect of tension fracture on existing road. We have established the mechanical model of vacuum preloading in vacuum preloading zone by using FLAC3D software and analyze the influence of the supporting structure, which one is the cast-in-place and the high pressure jet grouting pile. In the first supporting structure, the influential area of vacuum preloading on the expressway is 45 meters and the largest settlement is 2.37 centimeters. Obviously, the cast-in-place pile and the high pressure jet grouting pile can weaken the influence of vacuum preloading on the expressway obviously more.

Pilot tests on the usage of vacuum preloading combined with short prefabricated vertical drains (PVDs) to form a working platform for future soil improvement work were conducted at a land reclamation site in Tianjin, China. The short PVDs were connected using three methods – the conventional vacuum preloading method, fish-bone connectors and embedded horizontal pipes. To investigate the influence of PVD spacing, short PVDs were installed in square grids with spacings of 0·4 m and 0·6 m. The ground surface settlement, pore water pressures, water content and undrained shear strength of the soil were measured during the specific period of vacuum preloading. The pilot tests indicated that short PVDs connected using embedded vacuum pipes installed at 0·4 m spacing were the most suitable method to form a working platform on the surface of the dredged marine clay. This method yields a substantial saving on construction cost and time while exhibiting similar efficiency to the conventional vacuum preloading method. The undrained shear strength and degree of consolidation of the soil after 60 d of vacuum preloading were 23·6 kPa and 85·1%, respectively, which met the requirements for the working platform.

This paper analyzed the lateral buckling of pipelines located in Western Africa with ABAQUS software. The application of sleepers in practice is explored to guide the pipeline buckling controlling design.