Research on the Mixture Ratio Test for Rubble-Built Structure Mortar Filling Construction Technology

2020 ◽  
Vol 12 (6) ◽  
pp. 915-920
Author(s):  
Guo-Hui Jiang ◽  
Yu-Qing Li ◽  
Li Zhang ◽  
Senyan Jiang

Traditionally the rubble-built structures are constructed manually with low efficiency and long time consuming. It is studied in this research that the rubble-built structures are constructed with models according to designed profile. Firstly, the natural stones are piled up inside the model and then filled with self-compacting mortar into the inter-space of the stones at certain flow rate, and at last the models are removed after the mortar get hardened, so as to form the rubble-built structures with fast and mechanical construction process. The water and cement-sand mixture ratio for this construction process shall satisfy high flowability for flowing into the gaps of stones and also ensure the compressive strength of the structure. An indoor triangle box filling test is carried out to prove that the designed mixture ratio for filling the rubble-built structure is feasible and to determine the optimized mortar proportioning ratio.

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Yongli Xu ◽  
Guang Yang ◽  
Hongyuan Zhao

For cement-based materials, the curing temperature determines the strength gain rate and the value of compressive strength. In this paper, the 5% cement-stabilized macadam mixture is used. Three indoor controlled temperature curing and one outdoor natural curing scenarios are designed and implemented to study the strength development scenario law of compressive strength, and they are standard temperature curing (20°C), constant low temperature curing (10°C), day interaction temperature curing (varying from 6°C to 16°C), and one outdoor natural temperature curing (in which the air temperature ranges from 4°C to 20°C). Finally, based on the maturity method, the maturity-strength estimation model is obtained by using and analyzing the data collected from the indoor tests. The model is proved with high accuracy based on the validated results obtained from the data of outdoor tests. This research provides technical support for the construction of cement-stabilized macadam in regions with low temperature, which is beneficial in the construction process and quality control.


2021 ◽  
Vol 40 (4) ◽  
pp. 8493-8500
Author(s):  
Yanwei Du ◽  
Feng Chen ◽  
Xiaoyi Fan ◽  
Lei Zhang ◽  
Henggang Liang

With the increase of the number of loaded goods, the number of optional loading schemes will increase exponentially. It is a long time and low efficiency to determine the loading scheme with experience. Genetic algorithm is a search heuristic algorithm used to solve optimization in the field of computer science artificial intelligence. Genetic algorithm can effectively select the optimal loading scheme but unable to utilize weight and volume capacity of cargo and truck. In this paper, we propose hybrid Genetic and fuzzy logic based cargo-loading decision making model that focus on achieving maximum profit with maximum utilization of weight and volume capacity of cargo and truck. In this paper, first of all, the components of the problem of goods stowage in the distribution center are analyzed systematically, which lays the foundation for the reasonable classification of the problem of goods stowage and the establishment of the mathematical model of the problem of goods stowage. Secondly, the paper abstracts and defines the problem of goods loading in distribution center, establishes the mathematical model for the optimization of single car three-dimensional goods loading, and designs the genetic algorithm for solving the model. Finally, Matlab is used to solve the optimization model of cargo loading, and the good performance of the algorithm is verified by an example. From the performance evaluation analysis, proposed the hybrid system achieve better outcomes than the standard SA model, GA method, and TS strategy.


2014 ◽  
Vol 548-549 ◽  
pp. 1790-1794
Author(s):  
Xia Zhao ◽  
You Ping Ding ◽  
Xiu Yan Zhang

In order to analyze the effect of heat preservation, the heat preservation technology of detail structure, such as decorative lines of external walls, edge beam and edge column, windows, balcony and laying position of air conditioner, have been well treated under the system of thin plastered external wall based on EPS. Moreover, the technical-economy benefits of detail structure treatments have been analyzed by comparing with those without detail structure treatment. The results show that better heat preservation and economy benefits would be created by detail structure treatment, which could provide good reference for similar construction process.


2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Mingyang Chen ◽  
Wenzhong Zheng

To optimize the main components of reactive powder concrete (RPC) for various curing methods, based on the fluidity and compressive strength, an inclusive experimental research is conducted on 58 different mixture ratios. The results indicate that owing to the increase of the cement strength, the RPC fluidity decreases and the cement strength is not proportional to the compressive strength. The addition of the fly ash and the nano-microbead is an effective way to improve the fluidity, and it is required at the low W/B ratio. However, the influence of the SF grade on the strength and fluidity is almost negligible. By considering the fluidity, strength, and economy of RPC as crucial design factors, SF90 is suggested. The contribution of the steel fiber to the compressive strength cannot be ignored. The upper envelope value of the steel fibers is required for the structure to resist appropriately against the fire. According to the test results, the mixture ratio formula is proposed through considering the characters of different compositions and curing methods. The strength coefficient k1 is introduced to verify the influence of the steel fiber content, and the parameters fb, αa, and αb in the formula are reevaluated. A reasonably good agreement between the calculated strength and those obtained from the tests is reported, except for the case of W/B = 0.16 with P.O.52.5 cement. The basic steps for preparations of different RPC strengths are given, which provide a valuable reference to choose appropriate raw materials and mixture ratio design for different strength values.


2021 ◽  
Vol 11 (23) ◽  
pp. 11141
Author(s):  
Tae-Woong Kong ◽  
Hyun-Min Yang ◽  
Han-Seung Lee ◽  
Chang-Bok Yoon

High fluidity concrete exhibits an excellent self-compacting property. However, the application of typical high-fluidity concrete is limited in the normal strength range (18~35 MPa) due to the large amount of binder. Therefore, it is important to solve these problems by adding a viscosity modifying agent (VMA) with a superplasticizer (PCE), which helps to improve the fluidity of the concrete. In addition, the rheology and stability of the concrete with VMA can be improved by preventing bleeding and segregation issues. Current studies focused on the physical phenomena of concrete such as the fluidity, rheological properties, and compressive strength of normal-strength, high-fluidity concrete (NSHFC) with different types of a polycarboxylate-based superplasticizer (NPCE). The obtained results suggested that the combinations of all-in-one polycarboxylate-based superplasticizers (NPCE) did not cause any cohesion or sedimentation even stored for a long time. The combination of three types of VMA showed the best fluidity (initial slump flow of 595~630 mm) without any segregation and bleeding, and the compressive strength at 28 days was also found to be the highest: 34–37 MPa. From these results, the combination of PCE (2.0%) + HPMC (0.3%) + WG (0.1%) + ST (0.1%) showed an 18% higher plastic viscosity and -4.4% lower yield stress than Plain.


2011 ◽  
Vol 255-260 ◽  
pp. 65-69
Author(s):  
Hua Feng Deng ◽  
Min Zhu ◽  
Jing Guo ◽  
Tao Lu

Chimney is the building which is high but the horizontal cross section is small, so the high altitude work surface is small and difficult to construct, in which the stability of the scaffold and the safety of vertical transport equipment are especially important. For the serious problems arising in the prophase construction of the 50m chimney, double rows steel pipe scaffold was designed outside the chimney, and the vertical transportation uses the external grillage hoisting frame. Reformed the internal existing scaffold into pedestrian passage to separate people and material, and a detailed calculation analysis of the structural members such as scaffold, grillage hoisting frame and other structures was carried out. Large deformation, destabilization and other safety problems of the scaffold, grillage hoisting frame and other structures were not arising during the anaphase construction process, which indicates that the construction technical measures and calculation and analysis results are with important guiding significance to guarantee the smooth of the construction, and also can be referenced by other similar projects.


2011 ◽  
Vol 71-78 ◽  
pp. 1392-1397 ◽  
Author(s):  
Wen Xiong Huang ◽  
Li Ying Tan ◽  
Kang Jing Zhou

Cracks on the Joint Part between Pier and Girder, namely Block NO.0 in the construction process, has become one of the major diseases of continuous rigid-frame bridges. Based on the real construction technology, process and environment of Yuquanxi Bridge, the uneven distribution of stress caused by various factors is precisely analyzed by ANSYS. The shrinkage difference of concrete, the excessive hydration heat, and the sunshine temperature difference is accurately simulated respectively. By comparing the numerical results with actual cracks condition, the results prove that the theoretical analyse is accord with the actual situation, and the real reason of cracks on Block No.0 of Yuquanxi Bridge is uncovered. This study is of great practical value in preventing cracks and improving bridge construction technology.


2020 ◽  
Vol 39 (6) ◽  
pp. 9015-9026
Author(s):  
Lilin Wang

The light steel structure is always the common material of the movable plank house, and the new bud light steel system is the light steel system used for a long time after the earthquake. This paper discusses the mechanical system of the light steel structure of Huoshenshan hospital, which was built in ten days. In the process of building, the geometric form of roof stress has changed. In the actual structural design, the designer seldom takes the calculation of construction load into account, which is quite different from the actual construction process. So it is very important to simulate and monitor the whole process of structure installation. In this paper, the finite element software MIDAS / Gen is used for simulation analysis to ensure that the simulation analysis results are consistent with the construction process, the model material and the actual size are completely consistent, and the stress simulated by the software can meet the needs of the actual stress through the actual measurement.


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