Intelligent design of retaining wall structures under dynamic conditions

Haiqing Yang,Mohammadreza Koopialipoor,Danial Jahed Armaghani,Behrouz Gordan,Majid Khorami,M.M. Tahir 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.31 No.6

The investigation of retaining wall structures behavior under dynamic loads is considered as one of important parts for designing such structures. Generally, the performance of these structures is under the influence of the environment conditions and their geometry. The aim of this research is to design retaining wall structures based on smart and optimal systems. The use of accuracy and speed to assess the structures under different conditions is one of the important parts sought by designers. Therefore, optimal and smart systems are able to have better addressing these problems. Using numerical and coding methods, this research investigates the retaining wall structure design under different dynamic conditions. More than 9500 models were constructed and considered for modelling design. These designs include height and thickness of the wall, soil density, rock density, soil friction angle, and peak ground acceleration (PGA) variables. Accordingly, a neural network system was developed to establish an appropriate relationship between data to obtain safety factor (SF) of retaining walls under different seismic conditions. Different parameters were analyzed and the effect of each parameter was assessed separately. According to these analyses, the structure optimization was performed to increase the SF values. The optimal and smart design showed that under different PGA conditions, the structure performance can be appropriately improved while utilization of the initial (or basic) parameters leads to the structure failure. Therefore, by increasing accuracy and speed, smart methods could improve the retaining structure performance in controlling the wall failure. The intelligent design process of this study can be applied to some other civil engineering applications such as slope stability.

Investigation on the 3D Ground Settlement Induced by Shallow Tunneling considering the Effects of Buildings

Haiqing Yang,Fang Liu,Shaoze Lin 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.2

Complex tunneling process will inevitably result in varying degrees of ground movements. Prediction of ground movements is an essential part of planning, design and construction of a tunneling project. To address the predicting difficulty of ground movement, a correction parameter is introduced to the traditional ground movement solution both under two-dimensional and three-dimensional conditions on basis of the principle of conservation of ground loss. And the surface settlement caused by radial contraction of tunnel under different buried depth and excavation length, and induced by the action of building are studied through a series of model experiments. The experimental results show that the settlement value of any point along the middle line of the tunnel, is only about 50% of the measured value, which verify the necessity for correcting the tradition solutions. In addition, the applicability of the modified solution for different buried depth of tunnel axis under two-dimensional and three-dimensional conditions is also verified. Considering the uneven load distribution in the underlying soil caused by building load, we also introduced a load correction parameter and compared the modified solutions with the elastic analysis solution and the Peck formula. The comparison indicates that the modified solutions of two dimensions and three dimensions are more consistent with the experimental results, especially for the 3D surface settlement solution with large excavation length. And according to the results, the modified solution is more suitable to analyzing the surface settlement under the action of building load than previous modification, which further confirms the correction solutions to be an improvement to a close-form solution for ground surface settlement.

Logical Connectivity Prediction Models for VANET based on Nonlinear Regression and ELM : An Example of the AODV Protocol

Haiqing Liu,Licai Yang,Sijing Ding,Yunfeng Shi 보안공학연구지원센터 2014 International Journal of Future Generation Communi Vol.7 No.6

Differing from the physical connectivity of the topology structure, the logical connectivity of VANET considers both the interior network configuration and the external communication environment. Hence, the traditional mathematical analysis and modeling methods which are usually used in physical connectivity research are no longer suitable for the logical connectivity prediction. Taking the AODV protocol as an example, this paper simulates the effects of different road traffic parameters on logical connectivity probability and selects three main effect factors, roadway length, vehicle number and vehicle speed. Furthermore, the inner relation between the logical connectivity and the three road traffic parameters is studied based on data mining technique and then two logical connectivity prediction models are presented, the nonlinear regression-based model and the extreme learning machine-based model. Simulation results show that the two models are both with high accuracy in predicting the network logical connectivity under different road traffic environments.

Experimental Research and Finite Element Analysis on Structural Stability of Disc-Buckle Type Formwork Support

Jinfeng Dong,Haiqing Liu,Shengyong Xia,Yang Cheng,Ming Lei,Zimu Chen 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.3

In order to study the structural stability of the disc-buckle type formwork support, the multi-parameter experimental analysis of the disc-buckle type formwork support structure was carried out by using experimental and fi nite element analysis method. The infl uence parameters of working conditions, lift height, diagonal bracing and sleeve on the structural stability bearing capacity was mainly considered. The regularity of the buckling direction of the vertical pole, the stress at each typical position on the vertical pole and the axial force of the vertical pole was studied based on the experimental results. Based on the characteristics of semi-rigid connection joints, the correctness of the experimental results was verifi ed by fi nite element analysis, and the results show that reducing lift height and arranging diagonal bracing have remarkable infl uence on improving the structural stability bearing capacity. The usage of sleeves has little infl uence on the structural stability, and the corner pole was the worst position of the overall structural stability. The factors of working conditions and diagonal bracing have the remarkable infl uence on the buckling direction of the vertical pole. The factor of working condition has the most obvious infl uence on the stress uniformity of the vertical pole. The axial force of the vertical pole in the disc-buckle type formwork support structure presented a relatively uniform state from bottom to top in the loading process. The arrangement of diagonal bracing and the usage of sleeves have an infl uence on the uniformity of the axial force of the vertical pole. Compared with the fi nite element results, the error of the structural stability bearing capacity was within 6%, indicated that the fi nite element can accurately simulate the structural stability bearing capacity.

Analysis of Finite Element Mechanism of Axial Compressive Behavior of T-Shaped Stiffened Concrete-Filled Steel Tubular Stub Columns After Uniform Fire Exposure

Tong Zhang,Xuetao Lyu,Haiqing Liu,Yang Yu,Yang Xu 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.3

Based on the reasonable determination of material constitutive relationship and interaction model between concrete and steel tube, a fi nite element model of T-shaped stiff ened concrete-fi lled steel tube (TSCFST) stub column exposed to uniform fi re was established, and model reliability was verifi ed. Through the FE model, the working mechanism of the model in the whole process of loading was analyzed in detail. In the process of axial compression, the load distributions of steel tube and concrete, and the interaction between steel tube and concrete were discussed. This paper analyzed the eff ects of the main factors on residual bearing capacity of TSCFST stub columns, and put forward the calculation formula of the residual bearing capacity of TSCFST stub columns after uniform fi re exposure.

Anti-proliferation and pro-apoptosis effects of miR-582-5p in chronic lymphocytic leukemia via targeting HNRNPA1 and suppression of NF-κB

Wang Zengsheng,Li Yan,Kuang Xiaochuan,Guo Fang,Lang Tao,Mao Min,Zhang Xiaoyan,Yang Haiqing 대한독성 유전단백체 학회 2021 Molecular & cellular toxicology Vol.17 No.3

Background MicroRNAs (miRNAs) function as post-transcriptional mediators for genes involved in cancer progression, including chronic lymphocytic leukemia. MiR-582-5p has been identified as a tumor suppressor in various tumors. The antioncogenic role of miR-582-5p was then validated in this study. Objective Mononuclear cells were isolated from peripheral blood samples of patients with chronic lymphocytic leukemia and healthy donors. Expression of miR-582-3p in the mononuclear cells was examined by qRT-PCR. CCK8 assay was performed to detect cell viability, and cell cycle and apoptosis were evaluated by flow cytometry. Dual luciferase activity assay was performed to determine the targeting relationship between miR-582-3p and HNRNPA1, and western blot was performed to unravel the mechanism. Results MiR-582-5p was reduced in mononuclear cells of patients with chronic lymphocytic leukemia compared to healthy donors. Forced miR-582-5p expression reduced cell viability, and promoted apoptosis of chronic lymphocytic leukemia cells. Cell cycle was arrested in G0/G1 phase via miR-582-5p mimic. MiR-582-5p bound to HNRNPA1 (heterogeneous nuclear ribonucleoprotein A1) and down-regulated its expression. Silence of HNRNPA1 decreased cell viability, promoted apoptosis, and blocked cell cycle at G0/G1 phase through up-regulation of IκBα (IkappaBalpha). Moreover, HNRNPA1 silencing attenuated the promotive effect induced by miR-582-5p inhibitor on the progression of chronic lymphocytic leukemia. Conclusion MiR-582-5p demonstrated anti-proliferative and pro-apoptotic roles in chronic lymphocytic leukemia cell growth via down-regulation of HNRNPA1 and up-regulation of IκBα, thus inactivating NF-κB. Background MicroRNAs (miRNAs) function as post-transcriptional mediators for genes involved in cancer progression, including chronic lymphocytic leukemia. MiR-582-5p has been identified as a tumor suppressor in various tumors. The antioncogenic role of miR-582-5p was then validated in this study. Objective Mononuclear cells were isolated from peripheral blood samples of patients with chronic lymphocytic leukemia and healthy donors. Expression of miR-582-3p in the mononuclear cells was examined by qRT-PCR. CCK8 assay was performed to detect cell viability, and cell cycle and apoptosis were evaluated by flow cytometry. Dual luciferase activity assay was performed to determine the targeting relationship between miR-582-3p and HNRNPA1, and western blot was performed to unravel the mechanism. Results MiR-582-5p was reduced in mononuclear cells of patients with chronic lymphocytic leukemia compared to healthy donors. Forced miR-582-5p expression reduced cell viability, and promoted apoptosis of chronic lymphocytic leukemia cells. Cell cycle was arrested in G0/G1 phase via miR-582-5p mimic. MiR-582-5p bound to HNRNPA1 (heterogeneous nuclear ribonucleoprotein A1) and down-regulated its expression. Silence of HNRNPA1 decreased cell viability, promoted apoptosis, and blocked cell cycle at G0/G1 phase through up-regulation of IκBα (IkappaBalpha). Moreover, HNRNPA1 silencing attenuated the promotive effect induced by miR-582-5p inhibitor on the progression of chronic lymphocytic leukemia. Conclusion MiR-582-5p demonstrated anti-proliferative and pro-apoptotic roles in chronic lymphocytic leukemia cell growth via down-regulation of HNRNPA1 and up-regulation of IκBα, thus inactivating NF-κB.