Applied Mechanics and Materials Vols. 638-640

Abstract: Based on 75 cube specimens(100mm×100mm×100mm) of the super high early strength grouting material at elevated temperature,this paper describes the design of the high temperature test,compressive test and some relevant phenomena in testing,analyzes strength of the super high early strength grouting material at elevated temperature,and obtains the stress-temperature curves of the super high early strength grouting material at elevated temperature.By analyzing the staged characteristics of the curves,the regularity of the strength of the super high early strength grouting material at elevated temperature is discussed and some fitting mathematical formulas are suggested.

Abstract: Polyacrylic acid was synthesized and used as a retarder additive to prolong the setting time of gypsum plasters. The gypsum paste with the polyacrylic acid at the concentration of 0, 0.1%, 0.2%, 0.3%, 0.4% and 0.5% was studied. The water/gypsum mass ratio was 0.56. The influence of polyacrylic acid concentration on the initial and finial setting time, hydration temperature, morphology of hardened gypsum and mechanical property were extensively investigated. The results show that polyacrylic acid is favorable to increase the setting time which was associated with the reaction of carboxylic group and calcium from the hemihydrate dissolution. The morphology of hardened gysum varied when polyacrylic acid is used. The increase concentration of polyacrylic acid results in a decrease in hydration heat release, flexural and compressive strength.

Abstract: In order to solve the shortcomings of traditional methods of concrete curing in winter, proposed self-regulating heating cable new concrete curing methods. Several aspects were considered, about the heating cable length and heating time, heating temperature. According to energy conservation, heating and heat dissipation balance, derived formulas of heating cable normal use length and minimum. As conclusions is shown, first, the normal length design can controlled better heating temperature, it use the cable length and heating time, heating temperature two parameters to control the other parameters. Second, it is better heating efficiency, can be the overall warming state quickly. In addition, when the concrete pouring temperature is above 10 °C, it is not need additional heating, and it can choose minimum length design formula.

Abstract: In order to evaluate the flexural-tensile property of cement stabilized coal gangue roadbase materials, flexural-tensile strength and flexural-tensile modulus of materials, whose cement dosage range from 4% to 7%, were tested on the automatic servo universal material testing machine with one-third loading method. Based on the test data, correlation equations between cement dosage and flexural-tensile strength and flexural-tensile modulus were established. Results show that: cement dosage is an important influence factor of flexural-tensile property, both flexural-tensile strength and flexural-tensile modulus increase linearly with the increase of the cement dosage. Cement stabilized coal gangue roadbase materials have a good flexural-tensile property and suitable for base in the pavement structure.

Abstract: The paper study the deformation characteristics of the Prefabricated bamboo reinforced porous concrete slab through points with four points focused beam loading method. The results show that flexural behavior of prefab slab can be improved by adding bamboo reinforcement. Along with the increase of bamboo reinforcement ratio, deflection of prefab board will gradually reduce. Through the loading deflection curve, we can discover that the bamboo reinforced prefab slab with the linear elastic state, and the slab can withstand a certain load after cracking. Bamboo reinforced with strengthening and toughening effect for porous concrete, prefabricated bamboo reinforced porous concrete plate can be used better in slope protection engineering.

Abstract: The mechanical tests of hybrid steel-polypropylene fiber-reinforced concrete (HSPFRC) have been carried out. Concretes containing different volume fraction and aspect ratio of steel and polypropylene fibers mixed in one concrete grade were critically analyzed in terms of compressive, split tensile, axial tensile properties. Test results show that the fibers, when used in a hybrid form, can result in superior mechanical performance compared to their individual fiber-reinforced concretes.

Abstract: For the construction of large bridges, it is a very critical and difficult issue to obtain the pre-designed internal force state and geometric alignment through the control on the construction process when they are completed. This paper, according to the real-time monitoring results of the bridge structure in the construction process, assesses the deformation of the main components in primary construction phases as well as whether the variations of stress conform to the design requirements, security of construction process, and working state of structures.

Abstract: Construction methods of modern buildings are different from traditional buildings and they are the fundamental driving force of modernization of architecture. The article expands the research from three aspects, building materials, construction technology and human factors. The conclusion is the construction methods of modern architecture in Zhenjiang have the characteristics of scientific progress, localization and imbalance.

Abstract: An integral lifting scaffold is a external scaffolding which used in high-rise building structure and outside decoration. The integral lifting scaffold gets lifting and descending function based on the cantilever scaffold and the suspended scaffold, which have the falling prevention device and the upsetting prevention device. The hook hanging on the bearing supporting frame of the elevator was connected with the scaffold bearing supporting frame, the electric hoist achieved overall lifting or descending, the signal generator and automatic console controlled synchronous lifting. It was indicated by field application that the integral lifting scaffold can integrally lift and descend, and it can shard to lift and descend in order to meet the construction requirements of stage structure and decoration.

Abstract: Da Lian gym is a typical elliptical inclined mega-grid suspend-dome structure. Its complex structure form makes the prestressing construction more difficulty, and it is necessary to make a reasonable choice of construction scheme. In the paper, the summary about traditional prestressing construction schemes is made, and the construction schemes of radial cable tension and strut lifting were compared with construction simulation technology and tensile test. the results indicates that both methods can achieve the prestress construction of the structure, while more difficulties were contained in strut lifting method, therefore construction schemes of radial cable tension was suggested in actual construction. The research can provide theoretical basis for the structure’s prestressed construction plan, and also provide reference for similar projects.