聚苯乙烯泡沫的优点和应用

聚苯乙烯泡沫(简称EPS)是一种闭孔、轻质保温材料，在施工正确和做好防水的情况下，具有节能、良好的长期R值、耐水性以及尺寸稳定性，可用于所有的商业屋面系统，包括叠层屋面、改性沥青以及压顶的，机械固定的和全粘的屋面等。     

薄抹灰外墙外保温系统中EPS板形变的影响因素研究

研究了密度、陈化时间、温度、试样尺寸对EPS板薄抹灰外墙外保温系统中EPS板形变的影响。结果表明:大密度的EPS板尺寸稳定性优于低密度的EPS板;随着温度的升高,EPS板形变逐渐增大,当温度到80~85℃时,达到敏感温度点,产生不可逆的收缩形变明显加剧;EPS板形变性能的尺寸效应明显,随着试样尺寸的增大,形变率降低,但其形变量反而增加;陈化时间对EPS板的形变影响较大,随着陈化期的延长,EPS板的形变逐渐趋于稳定。     

干粉抹面聚苯板粘结剂的研究

介绍在大量试验的基础上研制出的一种新型干粉抹面聚苯板粘结剂。该产品大量应用于EPS和XPS外墙外保温工程．技术性能优异,具有推广价值。     

Mechanical properties of expanded polystyrene lightweight aggregate concrete and brick

In this study, mix proportion parameters of expanded polystyrene (EPS) lightweight aggregate concrete are analyzed by using Taguchi’s approach. The density, compressive strength and stress-strain behavior were tested. The optimal mixture of EPS lightweight aggregate concrete was selected among experiments under consideration to manufacture the lightweight hollow bricks. The results show that EPS dosage has the most significant effect on compressive strength of EPS lightweight aggregate concrete, then water and cement ratio, while the content of cement and sand ratio play a comparatively less important part. The relationship between density and compressive strength of EPS lightweight aggregate concrete is proposed as f_c = 2.43 × γ^2.997 × 10⁻⁹. The legitimacy of the use of EPS lightweight bricks made by EPS lightweight aggregate concrete is confirmed.     

EPS颗粒混合轻质土的施工技术及其应用实例

EPS颗粒混合轻质土是一种轻质、高强、环保、经济的新型土工材料,但国内还未见工程应用的报道。通过在新安江电厂88-70开关站交通道路工程中的应用实践,探讨了EPS颗粒混合轻质土的施工技术,证实了该材料可以起到缩短工期和提高工程安全性的目的。     

Study of cohesive soil deformability in a compression apparatus of different design

Compression test machines with a standard rigid soil ring are not free from shortcomings in design, the principle ones being possible jamming of the plate in the soil ring, existence of friction between the soil and the lateral surface of the rigid ring and consequently, a resulting non-uniformity in the stress-strain distribution throughout the sample. The newly devised compression apparatus in Moscow University by Kalachev-Filimonov (κ ?-1) is free from the said drawbacks. Indices of compressibility determined for clayey soils in the (κ ?-1) compression apparatus are 17–57% lower (25% on average) than the values yielded by tests in standard device. Utilization of this new compression test machine in defining collapsibility of loess soils is of great practical value as it permits more accurate classification of the soil properties.     

附着式聚苯乙烯板保温墙体施工工艺及特点

目前 ,墙体保温技术有了长足的发展 ,应用比较广泛且较理想的是采用聚苯乙烯板做保温材料的作法。目前聚苯乙烯板的安装方法有２种 :其一是用粘结剂 ,如市场上出售的ＫＥ胶、盾石干粉、专威特胶等多种胶结材料 ,把聚苯乙烯板粘结到墙体的外侧或内侧 ,然后用玻纤网格布增强 ;其二是钢丝网架聚苯乙烯夹芯板保温系统 ,它采用阻燃型聚苯乙烯泡沫板做板芯 ,两侧配以钢丝网片通过斜腹丝构成空间三维网架体系组成的３Ｄ板 ,又称ＧＳＪ板。ＧＳＪ板生产、安装成本较高。我们采用聚苯乙烯板直接安装能够降低工程造价。本文介绍的附着式聚苯乙烯板的施…     

膨胀聚苯板薄抹灰系统裂缝成因及预防措施

膨胀聚苯板薄抹灰系统在应用中常出现裂缝,使系统的保温、耐水、耐久和抗冻等性能大大降低。本文从材料角度对其系统开裂原因进行分析,并提出相应的预防措施。     

Environmental,health and safety concerns of decorative mouldings made of expanded polystyrene in buildings

Decorative tiles and mouldings made of polymeric foams are getting more popular in buildings. There are health, safety and environmental concerns on these products and their use in the buildings. In this paper, we report the results of the study and discuss about concerns of decorative mouldings made of expanded polystyrene (EPS). Physical damage to the structure of the building, potential harms to residents and health hazards were found as main concerns in this regard. The use of decorative mouldings made of EPS in the buildings is the subject to some considerations. The climate conditions play significant role in the feasibility of usage of decorative mouldings in the buildings. Although these products may add some aesthetic effects to the building's exterior view, the observations and results of this study do not support the use of the products in the buildings. Decorative mouldings bring significant safety and health risks, and it is recommended that for usage in buildings, particularly residential ones, the decorative moulding to be made of non-flammable light-weight materials or to be completely excluded from the buildings.     

Response of pavement foundations incorporating both geocells and expanded polystyrene (EPS) geofoam

The suitability of geocell reinforcement in reducing rut depth, surface settlements and/or pavement cracks during service life of the pavements supported on expanded polystyrene (EPS) geofoam blocks is studied using a series of large-scale cyclic plate load tests plus a number of simplified numerical simulations. It was found that the improvement due to provision of geocell constantly increases as the load cycles increase. The rut depths at the pavement surface significantly decrease due to the increased lateral resistance provided by the geocell in the overlying soil layer, and this compensates the lower competency of the underlying EPS geofoam blocks. The efficiency of geocell reinforcement depends on the amplitude of applied pressure: increasing the amplitude of cyclic pressure increasingly exploits the benefits of the geocell reinforcement. During cyclic loading application, geocells can reduce settlement of the pavement surface by up to 41% compared to an unreinforced case – with even greater reduction as the load cycles increase. Employment of geocell reinforcement substantially decreases the rate of increase in the surface settlement during load repetitions. When very low density EPS geofoam (EPS 10) is used, even though accompanied with overlying reinforced soil of 600 mm thickness, the pavement is incapable of tolerating large cyclic pressures (e.g. 550 kPa). In comparison with the unreinforced case, the resilient modulus is increased by geocell reinforcement by 25%, 34% and 53% for overlying soil thicknesses of 600, 500 and 400 mm, respectively. The improvement due to geocell reinforcement was most pronounced when thinner soil layer was used. The verified three-dimensional numerical modelings assisted in further insight regarding the mechanisms involved. The improvement factors obtained in this study allow a designer to choose appropriate values for a geocell reinforced pavement foundation on EPS geofoam.     

EPS轻骨料混凝土的吸湿性和透气性研究

作为外墙保温材料使用时,EPS轻骨料混凝土应当具备较低的吸湿性和较高的透气性.研究了密度、可再分散乳胶粉掺量和硬脂酸钙憎水剂掺量对EPS轻骨料混凝土吸水率和水蒸气透过率的影响.结果表明:降低密度和增加可再分散乳胶粉的掺量均能显著提高EPS轻骨料混凝土的吸水率和水蒸气透过率;掺加硬脂酸钙能够显著降低吸水率,当其掺量达到胶凝材料质量的4％时,EP5轻骨料混凝土吸水率的降低幅度达到10％,同时能够保持较高的水蒸气透过率.     

Design and construction of expanded polystyrene embankments Practical design methods as used in the United Kingdom

This paper covers the history of the use of expanded polystyrene ( ) in light weight fill for road embankments. UK design requirements and physical properties of the foam are covered together with two case studies.     

Creep and long-term strength of clayey soils in triaxial compression

The results of experimental investigations of the creep and long-term strength of clayey soils, which the authors conducted on a stabilometric type of triaxial-compression machine, are discussed. Equations describing laws governing vanishing and nonvanishing creep with allowance for dilatancy, and also a variant of the time-dependent equation of the limiting stress state are proposed. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 1, pp. 10–14, January–February, 1997.     

A proposed lightweight fill for embankments using cement-treated Yangzi River sand and expanded polystyrene (EPS) beads

This paper presents a new kind of material for use in highway embankments in the soft soil of the Yangzi River delta. The experimental study was carried out first to evaluate the effectiveness of the proposed material, using different mixtures of river sand, cement and expanded polystyrene beads. This was confirmed by numerical modeling which indicated both its suitability as regards strength and a reduced settlement compared with the general lime stabilized soil embankments. The environmental advantage is that it utilized river sand which has to be removed to retain the profile of the river bed.     

泡沫玻璃和聚苯板外墙外保温系统性能及施工方法

介绍泡沫玻璃和聚苯板2种外墙外保温隔热体系的材料性能、墙体构造和施工方法,并对这2种保温隔热体系在广西南宁市广运·都市景苑工程项目中的实际应用进行了技术总结.     

Explainable probabilistic deep learning framework for seismic assessment of structures using distribution-free prediction intervals

A new probabilistic framework is proposed for providing a distribution-free prediction interval (PI) of seismic responses required for various earthquake engineering applications. The framework overcomes the limitation of point prediction models and avoids the complexity of traditional probabilistic methods. The framework utilizes a few assumptions of probability distributions and requires no prior assumed statistical distribution for the PI. Ensemble probabilistic deep learning models (DLMs) are used to provide quality-driven PIs of seismic responses for low- to mid-rise buildings with limited irregularity. Considering these systems and ground motions with the aid of Monte Carlo simulation and nonlinear time-history analysis (NLTHA), huge datasets are generated for training. To have an insight into the probabilistic DLM, explainable artificial intelligence techniques are used. The superiority of the proposed framework in quantifying uncertainties is validated by comparison with the conventional Bayesian method. In addition, its applicability is investigated by providing bounds of seismic fragility curves, life cycle cost, and resilience index obtained by NLTHA for a benchmark case study model. The results showed that the proposed framework is robust and outperforms the conventional Bayesian method in uncertainty quantification for the considered dataset.     

Rheological parameter estimation for the prediction of long-term deformations in conventional tunnelling

The long-term deformations of mountain tunnels, which attract more and more attentions, are closely related to the time-dependent features of the surrounding rock mass. However, it is not easy to determine an appropriate rheological model and its corresponding parameters for a certain engineering instance. This paper presents a rheological parameter estimation technique by using error backpropagation neural network (BN) and genetic algorithm (GA). The application of the proposed technique to an engineering instance, Ureshino tunnel line I on Nagasaki expressway, is expatiated in detailed. The stochastic nature of the proposed technique is also discussed through case studies. It is proved that the proposed technique can provide the engineer with an optimal estimation of the rheological parameters, which can help the prediction of long-term deformations of mountain tunnels in the future.     

ZL胶粉聚苯颗粒贴砌聚苯板外墙外保温系统综合性能研究与分析

本文分别从系统基本构造、施工方法、施工适应性、防火安全性、粘结性、抗负风压性、抗裂性、耐候性、粘贴面砖可行性、体系价格及节能减排等多方面分析了ZL胶粉聚苯颗粒贴砌聚苯板外墙外保温系统的特点。综合分析结果表明：ZL外墙外保温系统具有优良的防火和耐候性,符合国家发展循环经济,利废再生的科学发展观。     

Experimental research on employed expanded polystyrene (EPS) for lightened sulfate heave of subgrade by thermal insulation properties

In sulfate-rich soils with high sodium sulfate contents, sulfate heave can occur and then generate severe damages to engineering facilities such as pavement, airplane runway due to the hydration of thenardite or crystallization of mirabilite when the temperature is below 32.4 °C. Based on the significant effect of expanded polystyrene (EPS) geofoam in reducing the temperature variations, a comparative experimental investigation on the sulfate heave of subgrade generated by the artificial coarse-grained saline soil with and without EPS material is conducted. Parameters of swell displacement and temperature fluctuation obtained from this comparative experiment are further validated and analyzed. The X-Ray Diffraction (XRD) measurement result is used to demonstrate the performance of EPS in microstructure. Test results indicate that: (1) The presence of crystallized mirabilite is proved within subgrade with saline soil when the temperature drops below 32.4 °C; (2) sulfate heave of subgrade is dependent on temperature fluctuation, but more specifically, on the temperature drop that occurs below 32.4 °C; and (3) EPS thermal insulation can reduce sulfate heave in pavement subgrade by effectively reducing the temperature fluctuation within the subgrade.Ce database subject headingsHeave; Hydration; Salinity; Subgrades; Sulfates; Temperature effects.     

Application of the expanded distinct element method for the study of crack growth in rock-like materials under uniaxial compression

The expanded distinct element method (EDEM) was used to investigate the crack growth in rock-like materials under uniaxial compression. The tensile-shear failure criterion and the Griffith failure criterion were implanted into the EDEM to determine the initiation and propagation of pre-existing cracks, respectively. Uniaxial compression experiments were also performed with the artificial rock-like samples to verify the validity of the EDEM. Simulation results indicated that the EDEM model with the tensile-shear failure criterion has strong capabilities for modeling the growth of pre-existing cracks, and model results have strong agreement with the failure and mechanical properties of experimental samples. The EDEM model with the Griffith failure criterion can only simulate the splitting failure of samples due to tensile stresses and is incapable of providing a comprehensive interpretation for the overall failure of rock masses. Research results demonstrated that sample failure primarily resulted from the growth of single cracks (in the form of tensile wing cracks and shear secondary cracks) and the coalescence of two cracks due to the growth of wing cracks in the rock bridge zone. Additionally, the inclination angle of the pre-existing crack clearly influences the final failure pattern of the samples.