Expanded Polystyrene Content Research Articles

Experimental study on preparation and performance of the Corn Straw Fiber (CSF) reinforced EPS concrete

With the full factor experimental design method carried out, 20 sets of EPS concrete specimens with different mass fractions of Corn Straw Fiber (CSF) and Expanded-Polystyrene (EPS) particles were designed to study their density, water absorption, compressive strength, flexural strength, splitting tensile strength, mass loss and strength loss after freeze-thaw cycles, and changes in thermal conductivity, to evaluate the effect of CSF content and EPS content on the properties of EPS cement-based composites. The experimental results show that adding CSF can improve the mechanical properties of EPS concrete while reducing its density, the maximum increase rate of compressive strength is 69.7 %, with a maximum value of 1.12 MPa; The maximum improvement rate of flexural strength is 127.38 %, with a maximum value of 0.885 MPa; The maximum improvement rate of splitting tensile strength is 68.07 %, and the maximum value is 0.256 MPa. After 50 standard freeze-thaw cycles, straw fibers can delay the quality loss of EPS concrete, but show adverse effects on its strength loss, the maximum quality loss rate is 4.23 %, and the maximum loss rates for the three strengths are 24.46 %, 24.22 %, and 24.61 %, respectively. In addition, in terms of improving the thermal insulation performance of EPS concrete, the role of the two aggregates is manifested as EPS > CSF, and the thermal conductivity coefficient values under different aggregate dosages were obtained, when the content of EPS is 1.4 % and the content of CSF is 4 %, the minimum thermal conductivity value is 0.0402 W/(m·°C), and the thermal conductivity coefficient of calcium silicate board is 0.0378 W/(m °C) by the thermal conductivity coefficient formula of composite materials. which can serve as a reference for selecting building insulation materials in areas with high temperature differences.

Research on the mechanical properties of EPS lightweight soil mixed with slag.

Expanded polystyrene (EPS) bead lightweight soil composites are a new type of artificial geotechnical material with low density and high strength characteristics that can be widely used in engineering projects. To promote the wide application of EPS bead lightweight soil in engineering, when slag is used to replace part of the cement as a binding agent, it can better improve the effect of soil and reduce engineering costs. The mechanical properties of EPS lightweight soil mixed with slag were analyzed by conducting an unconfined compressive strength (UCS) test and triaxial test on lightweight soil with different EPS bead contents and slag contents. The particle sizes of the EPS beads are 1~3 mm, the EPS contents are 1%, 2%, 3%, and 4%, and the slag-cement composite binding agents are 10%, 15%, 20% and 25%. The results show that the UCS decreases significantly with increasing EPS bead content at different EPS bead contents and slag contents; the UCS of the specimen with 30% slag content is the largest; and the UCS of lightweight soil without slag is comparable to that of lightweight soil with a slag content of approximately 60%. The peak stress in triaxial increases with increasing confining pressure, and the modulus of deformation decreases linearly with increasing EPS bead content. the slag-cement composite binding agent has a significantly better reinforcing effect than single mixed cement. The stress‒strain curves of EPS lightweight soil mixed with slag exhibits hardening and softening characteristics. EPS bead content and slag content determine the stress‒strain characteristics of the EPS lightweight soil mixed with slag. The macromechanical properties based on the microscopic mechanism of the EPS lightweight soil mixed with slag shows that different slag contents affect the failure pattern of EPS lightweight soil mixed with slag. The research results can provide a reference for engineering design and application.

Structural Performance of Lightweight Fiber Reinforced Polystyrene Aggregate Self-Compacted Concrete Beams

This study aims to investigate experimentally the flexural behavior of lightweight Self-Compacted Concrete (SCC) beams made by Expanded Polystyrene (EPS) concrete and reinforced with rebars and steel fibers. To achieve the aims of this study, seven simply supported EPS lightweight fiber-reinforced concrete beams were fabricated and tested up to failure to study the effects of EPS content and the volume fraction of the steel fibers on their flexural behavior. The tested specimens were divided into two groups with one additional reference beam to be cast without using EPS or steel fibers. In the first group, three lightweight specimens were constructed using 25% EPS beads and were reinforced with 0%, 0.75%, and 1.5% steel fiber volume fractions. The second group is similar to the first group but was fabricated using 50% EPS beads. The test results showed that the mechanical properties of the hardened concrete were significantly reduced due to polystyrene EPS beads with some enhancement when steel fibers were added to the concrete mix. The flexure strength of EPS-LWT concrete beams was significantly reduced due to the polystyrene EPS beads. Furthermore, the results revealed remarkable enhancement in the flexure strength of the tested beams due to the steel fiber reinforcement.

Punching shear capacity of expanded polystyrene (EPS) lightweight concrete flat slabs without shear reinforcement

This work presents an experimental and theoretical study on the punching shear behavior of Lightweight Concrete Slabs. Lightweight obtained using Expanded polystyrene (EPS) beads as partial coarse aggregate’s replacement, without adding supplementary bonding additives, to reduce concrete density from 2400 to 1800 kg/m3. The EPS content, concrete strength and column aspect ratio were test parameters. Five groups of concrete prepared by partially replacing natural coarse aggregate with 0%, 10%, 20%, 30% and 40% (by volume) of EPS balls. Ten reinforced concrete slabs without shear reinforcement with a monolithic column were tested under concentric loading. The study aimed to examine the effect of the EPS on the density and compressive strength of concrete and eventually on the flat slabs punching capacity. Five series of mixtures identified and compared with conventional normal weight concrete. Results showed that with increasing EPS content, rate of reduction in concrete strength is faster than the reduction in concrete density. Also, showed that the failure base area increased while the concrete density decreased, this yielded a higher punching capacity compared to rate of decrease in the concrete strength. International standards models showed overestimation of punching shear capacity and didnot reflect the reduced concrete strength action of lightweight concrete.

Physical and Mechanical Properties of Expanded Polystyrene (EPS) Particle Lightweight Soil under Freeze-Thaw Cycles.

In seasonally frozen regions, the bearing capacity of soil decreases and gradually deteriorates after undergoing freeze-thaw cycles. To resolve this problem, based on the idea of frost-resistant filling materials, a filling scheme of expanded polystyrene (EPS) particles lightweight soil in cold regions was proposed. Unconfined compressive strength, direct shear, and micro-SEM tests were carried out to study the physical and mechanical properties of EPS particles lightweight soil under freeze-thaw cycles. The results indicate that the EPS particle lightweight soil has good frost resistance and can be used as frost-resistant filling material in cold regions. Under freeze-thaw cycles, EPS particle lightweight soil maintains good integrity; EPS particles can effectively reduce the frost heave rate, mass loss rate, and compressive strength loss rate of lightweight soil. The compressive strength depends on the EPS and cement contents: it decreases with an increase in the EPS content and increases with an increase in the cement content. The strength loss rate decreases with an increase in both. When the content of EPS is larger (more than 2%), the soil cement bound with EPS particles is limited, and the performance of lightweight soil decreases. The shear strength and cohesion decrease with an increase in freeze-thaw cycles and EPS content, and the internal friction angle follows no obvious rule with regard to the increase in freeze-thaw cycles but decreases with an increase in the EPS content. Based on the experimental results, an empirical formula for the compressive strength of EPS particle lightweight soil under freeze-thaw cycles was proposed. This study can provide a reference for the engineering design and application and provide new ideas for resolving freeze-thaw problems in construction engineering in cold regions.

Multi-Response Optimization of Semi-Lightweight Concrete Incorporating Expanded Polystyrene Beads

The utilization of expanded polystyrene (EPS) beads in semi-lightweight concrete (SLC) intended for repair and building applications has gained great attention in recent years. This study examines the effect of mix design parameters including binder content, water-to-binder ratio (w/b), EPS content, and silica fume (SF) additions on the mechanical properties and durability of SLC mixtures. The experimental program was carried out following the Taguchi approach for four parameters, each having three levels, to produce an L9 orthogonal array. The performance criteria under investigation were the superplasticizer demand, density, compressive strength, splitting tensile strength, ultrasonic pulse velocity, water absorption, sorptivity, and abrasion resistance. Test results showed that the w/b and EPS content were the most contributing parameters that altered the SLCs performance. The multi-response optimization method (TOPSIS) revealed that superior performance could be achieved using a binder content of 375 kg/m3, a w/b of 0.45, an EPS content of 3 kg/m3, and a SF replacement rate of 8%. The mix design parameters were utilized to create multivariate regression models to predict the SLCs mechanical and durability properties. Such data can be of particular benefit to engineers seeking the use of lightweight materials for sustainable construction with optimized durability and a reduced cement carbon footprint.

Dynamic behavior of EPS amended lightweight soil under cyclic loading

The dynamic behavior of expanded polystyrene (EPS) particle amended lightweight soil was explored using consolidated undrained dynamic and monotonic triaxial tests conducted on samples of lightweight soil with different mixing ratios. The dynamic stress, dynamic strain, and dynamic pore pressure time history curves, and shear strength criterion were studied. As a kind of structural soil, the dynamic strain time history curves of lightweight soil could be divided into three stages as the vibration compaction, vibration deformation and vibration failure stages according to the cumulative deformation rate of dynamic strain, but the vibration compaction stage was not obvious. The dynamic strain accumulation for lightweight soil was mainly single amplitude in compressive region. The deformation rate during the vibration failure stage for the lightweight soil was larger than that of the remolded soil owing to its increased stiffness and brittleness with added cementation. Unlike that of the remolded soil, dynamic pore pressures fluctuated markedly in lightweight soil tests. The dynamic pore pressure development of lightweight soil was found to relate to the mixing ratios of its components and the confining pressures. For lightweight soil samples with high EPS particle mixing ratio, the dynamic pore pressures remained in the positive range, increasing unsteadily with some fluctuation. However, for lower EPS content samples in different confining pressures, the dynamic pore pressure showed decreasing trends into the negative range, again changing unsteadily with fluctuation, showing a trend of suction and soil skeletal dilation. Based on analysis of results, it was determined that, general pore pressure, limit equilibrium and yield criterias were not suitable to describe the dynamic behavior of lightweight soil, while the dynamic strain criterion was suitable. Excluding the plastic deformation range, the single amplitude dynamic compression strain of 5% was recommended as the dynamic strain criterion to determine dynamic strength of lightweight soil.

Study on Dynamic Modulus and Damping Characteristics of Modified Expanded Polystyrene Lightweight Soil under Cyclic Load.

In recent years, expanded polystyrene (EPS) lightweight soil has been widely used as subgrade in soft soil areas because of its light weight and environmental protection. This study aimed to investigate the dynamic characteristics of sodium silicate modified lime and fly ash treated EPS lightweight soil (SLS) under cyclic loading. The effects of EPS particles on the dynamic elastic modulus (Ed) and damping ratio (λ) of SLS were determined through dynamic triaxial tests at various confining pressures (σ3), amplitudes, and cycle times. Mathematical models of the Ed of the SLS, cycle times, and σ3 were established. The results revealed that the EPS particle content played a decisive role in the Ed and λ of the SLS. The Ed of the SLS decreased with an increase in the EPS particle content (EC). The Ed decreased by 60% in the 1-1.5% range of the EC. The existing forms of lime fly ash soil and EPS particles in the SLS changed from parallel to series. With an increase in σ3 and amplitude, the Ed of the SLS gradually decreased, the λ generally decreased, and the λ variation range was within 0.5%. With an increase in the number of cycles, the Ed of the SLS decreased. The Ed value and the number of cycles satisfied the power function relationship. Additionally, it can be found from the test results that 0.5% to 1% was the best EPS content for SLS in this work. In addition, the dynamic elastic modulus prediction model established in this study can better describe the varying trend of the dynamic elastic modulus of SLS under different σ3 values and load cycles, thereby providing a theoretical reference for the application of SLS in practical road engineering.

Selected Properties of Veneered Lightweight Particleboards with Expanded Polystyrene.

The aim of this study was to improve the properties of lightweight particleboards by their veneering. The industrially produced wood particles, rotary-cut birch veneer, expanded polystyrene (EPS) granules and urea-formaldehyde (UF) resin were used to manufacture non-veneered and veneered boards in laboratory conditions. The boards were manufactured with different densities of 350, 450 and 550 kg/m3 and with various levels of EPS content 4, 7 and 10%. Boards without EPS granules as the reference were also manufactured. Bending strength (MOR), modulus of elasticity in bending (MOE), internal bond (IB) strength, thickness swelling (TS) and water absorption (WA) of lightweight particleboards were determined. This study confirmed that veneering of lightweight particleboards by birch veneer improved mechanical properties significantly. The MOR and MOE of veneered boards throughout the whole density range of 350–550 kg/m3 meet the requirements of the CEN/TS 16368 for lightweight particleboards types LP1 and LP2. The IB strength of veneered boards only with density of 550 kg/m3 meets the requirements of CEN/TS 16368 (type LP1). The MOR, MOE and IB of non-veneered boards also meet the requirements of CEN/TS 16368 (type LP1) except boards with density of 350 kg/m3 for MOR and MOE, and except densities of 350 and 450 kg/m3 for IB.

Physical and mechanical properties of cotton straw fibre and expanded polystyrene cementitious composite

This aim of this work was to develop a low-cost, high-performance cement-based composite using straw cotton straw fibre (CSF) and expanded polystyrene (EPS). To this end, cement mortar specimens with different proportions of CSF (5%, 10% and 15%) and EPS (1%, 2% and 3%) were prepared. A control group (CG), without CSF or EPS was also tested. The compressive strengths, anti-splitting and flexural strengths of the specimens with different mix proportions were tested at for 7 days and 28 days. The thermal conductivity and water absorption of the specimens at 28 days were also measured. It was found that, for a constant content of CSF or EPS, the compressive strength and axial compressive strength of the samples at 28 days decreased with an increase of EPS or CSF content. The maximum compressive and axial compressive strengths of the CSF–EPS specimens were 37% and 42.6% lower than those of the CG, respectively, whereas the maximum flexural and anti-splitting strengths were 33% and 94% more than those of the CG. With an increase in the content of CSF and EPS, the water absorption of the specimens increased, whereas the thermal conductivity decreased. The cementitious composite made with 5–10% CSF and 1–2% EPS met the requirements for the mechanical properties and thermal insulation performance of self-insulating blocks.

Properties of Lightweight Controlled Low-Strength Materials Using Construction Waste and EPS for Oil and Gas Pipelines

Due to its particularity and importance, long-distance oil and gas pipelines need to be well protected from damage by backfill materials. In this study, construction waste and expanded polystyrene (EPS) were used to replace conventional fine aggregate, and ethylene vinyl acetate-resin (EVA) was used to modify the surface of EPS to prepare lightweight controlled low strength materials (CLSM). Lightweight CLSM was tested in mechanics and physics and its microstructure was studied using microscopic analysis methods. The results revealed that the surface modification of EPS by EVA could greatly improve the compatibility of EPS with inorganic cementitious materials and prepare CLSM with a fluidity greater than 200 mm. EPS and cement content in cementitious materials play an important role in the development of material strength. When the volume ratio of EPS to construction waste was 2, and the content of cement in the cementitious materials was 35%, CLSM’s unconfined compressive strength at 28 days was only 0.48 MPa. In order to obtain the lightweight CLSM that meets the mechanical properties, the EPS content should not be too large. It can be concluded from the microscopic analysis that the increase of EPS content will lead to poor pore uniformity of the specimen, forming a loose mesh structure of defects, which is not conducive to the development of strength. In this study, EPS and construction waste are used to provide a green idea for preparing lightweight controlled low strength materials, which provides a reference for the backfill protection of the material in oil and gas pipelines in the future.

A bounding surface plasticity model for expanded polystyrene-sand mixture

This study presents a bounding surface plasticity model to capture the stress-strain responses of expanded polystyrene (EPS)-sand mixture with various EPS content levels. Based on the mechanical responses in isotropic and triaxial tests, a generalized void ratio concept is applied to the potential deformation characteristics of EPS beads. Subsequently, the void ratio-isotropic stress curve can be expressed in a semi-log space, which shows a three-linear-segments manner corresponding to three typical mechanisms (elastic compression, normal compression and sand particle embedding in EPS beads). The plasticity model is formulated within the framework of critical state concept. For the sake of simplicity, the raindrop shaped yield function has been applied to describe the bounding surface, with a non-associate flow rule being adopted to capture the plastic deformation. Thus, this model requires fewer model parameters, most of which can be calibrated through conventional isotropic and triaxial test. By considering the weakening effect caused by including EPS, special treatment has been applied to EPS proportion dependent parameters. The capability of the proposed model has been demonstrated through a model simulation on EPS-sand mixtures with different EPS proportions and various confining pressures.

Effect of Expanded Polystyrene Particle Size on Engineering Properties of Clayey Soil

The particle size of expanded polystyrene (EPS) has an effect on engineering properties of EPS‐clay blends. However, the effect of differences between EPS particle size groups subdivided within 1–3 mm on engineering properties is usually ignored. In this study, different particle sizes of EPS pellets have been considered to separately investigate the effect on the optimum water content (OWC), maximum dry density (MDD), unconfined compressive strength (UCS), ductility, coefficient of permeability, and compression index of EPS‐clay blends. Results show that the MDD, ductility, hydraulic conductivity, and compression index of EPS‐clay blends do not increase with the increase in the EPS particle size in the range of 0.3–3 mm, while the OWC and UCS do not decrease. For a given EPS content, among samples with the EPS particle size of 0.3–1 mm, 1‐2 mm, and 2‐3 mm, the MDD and UCS of EPS‐clay blends with 1‐2 mm in EPS particle size are the largest, while the OWC, ductility, coefficient of permeability, and compression index are the smallest. Microstructure analyses reveal that, for samples with the EPS particle size of 1‐2 mm, the pore volume is lower and the microstructure is denser, which are the main reasons why the EPS particle size can influence engineering properties of EPS‐clay blends.

Dynamic compressive properties of novel lightweight ambient-cured EPS geopolymer composite

Geopolymer as eco-friendly and alternative cementitious material has been intensively investigated. In a previous study, Expanded Polystyrene (EPS) of volume fractions of 10%, 20% and 30% was mixed into the ambient-cured plain geopolymer mortar (GM) to form lightweight geopolymer composite (LGC). The static mechanical properties were tested and reported. The developed LGC can be used in various applications such as road barriers, tunnel cushions and lightweight building products i.e. bricks and panels, which could be subjected to dynamic loads such as impact or blast. Therefore, its dynamic properties need to be investigated. In this study, dynamic compressive properties of LGC were investigated by using Ø100-mm split Hopkinson pressure bar (SHPB). The failure processes and the failure modes of plain GM and LGC specimens with various EPS contents under different strain rates, as well as the stress–strain curves and the energy absorption capacity were compared. The strain rate effect on the dynamic compressive strength, axial strain at peak stress and normalized energy absorption capacities were compared and analysed. The test results showed that dynamic compressive properties and energy absorption capacity of LGC with more EPS contents were more sensitive to the strain rate. Based on the testing results, the empirical formulae of dynamic increase factor of compressive strength and energy absorption versus strain rate were proposed.

Efficacy of expanded polystyrene as fine aggregate in cement mortars modified with latex paint as an alternative to polymer admixture

Abstract In this present study, the effectiveness of expanded polystyrene (EPS) waste used as 20, 40 and 60% fine sand replacement in development of lightweight cement composite was evaluated. The cement mortar was strengthened by 10% low cost latex paint emulsion as an alternative to the more expensive polymer admixtures. Six different mix designs were produced and tested for compressive and split tensile strength according to BS EN standards. Scanning electron microscope (SEM) analysis was also conducted to analysis the micrograph of the samples. It was observed that as the EPS content, latex paint polymer admixture and curing days were increased, marginal increment in compressive strength was obtained. However, EPS fines were most effective in improving the split strength while latex paint admixture had comparatively less part to play in the strength development. The micrograph images showed that the EPS fines were uniformly distributed within the microstructure and the latex paint developed polymer films. These mechanisms coupled with the cement hydrate products were responsible for the enhanced strength observed in the samples.

Properties of eco-friendly pervious concrete containing polystyrene aggregates reinforced with waste PET fibers

A huge amount of expanded polystyrene (EPS) and PET plastics are produced every year all around the world. However, if not treated properly, after their consumption, EPS and PET caused numerous environmental problems. Therefore, the utilization of these wastes in concrete production can contribute to the sustainability of construction materials. This experimental study aims to investigate the behavior and properties of pervious concrete incorporating both EPS aggregates and waste PET fibers. A total of ten concrete mixtures were designed with different percentages of PET fibers and the same amount of EPS content. The investigated parameters included: abrasion resistance, dry density, compression as well as flexural strength, porosity ratio and water permeability coefficient. From the results obtained in this study, it has been shown that the proposed mixes are reliable to use in the construction field. The compressive strength, abrasion resistance and density decreased by incorporating EPS and PET fibers. However, the flexural strength increased by using PET fibers up to 1% in volume. On the other hand, the porosity ratio and the water permeability coefficient increased through the addition of PET fiber. The empirical models among different properties were also provided. This experimental study can be contributed to promote sustainable construction materials as mixtures contained a considerable amount of waste materials.

Effect of expanded polystyrene content and press temperature on the properties of low-density wood particleboard

In this study, three-layer low-density (about 400 kg/m3) particleboards consisting of a mixture of wood particles and expanded polystyrene (EPS) were manufactured. EPS bead was incorporated in the core layer as a light filler. The influence of EPS content (0 %, 2,5 %, 5 %, 7,5 %, 10 %, and 12,5 %) and press temperature (110 °C and 140 °C) on the microstructure, density profile, bending properties, internal bond and thickness swelling of the panels were investigated. Results showed that incorporation of EPS beads filled in the voids between wood particles improved the core layer integrity, and generated a more pronounced density profile. Consequently, the bending properties and internal bond of panels adding EPS were remarkably improved, and the thickness swelling was decreased. However, the variation of the number of EPS from 2,5 % to 12,5 % had no significant effect on the bending properties and thickness swelling. Comparing the two press temperatures, higher temperature (140 °C) was more favourable in control panels without EPS as filler. For panels adding EPS filler, 140 °C had a negative effect on the properties of panels, especially at high EPS contents (10% and 12,5%), attributing to the shrinkage of EPS bead under press temperature that is much higher than its glass transition temperature (104 °C)

Dynamic properties of EPS-sand mixtures using cyclic triaxial and bender element tests

In this study, a series of strain-controlled cyclic triaxial as well as bender element tests are carried out, so that the dynamic properties of mixtures of sand and expanded polystyrene (EPS) beads can be assessed under large and small-scale shear strains, respectively. The effect of various parameters such as shear strain amplitude, confining pressure (25 kPa, 50 kPa and 100 kPa) and EPS weight content (up to 2% by weight) on the small strain shear modulus, secant shear modulus and damping ratio is investigated. Laboratory results indicated that the values of shear velocity and shear modulus obtained from the bender element tests decrease with increasing EPS content. The results also revealed that the damping and shear modulus of the samples are highly dependent on the weight percentage of EPS, such that the increase in EPS content results in the increase of damping ratio up to 100% or even more under constant confining pressure. On the contrary, for all the values of confining pressure, the shear modulus of the mixture undergoes a significant reduction with increasing EPS content. Moreover, it is shown that the confining pressure has a important impact on both the soil damping ratio and shear modulus.

Numerical and Experimental Investigations of the Influence of Grain Size on the Compressibility of Sand–EPS Mixtures

In the past decade, there have been numerous investigations on the physical and mechanical properties of the lightweight composite materials. The application of the expanded polystyrene (EPS), which is a super lightweight material with very low density and potentially high compressibility, has been studied by many researchers. This paper presents experimental and numerical investigations on the compressibility of the sand–EPS mixtures. The influence of grain size variations on the compressibility of the composite samples was studied using the standard Casagrande oedometer apparatus in the laboratory. Moreover, a series of discrete element modeling (DEM) simulations were carried out to verify the results of the laboratory tests. Since it was aimed to elaborate on the behavior of completely rounded granules, steel pellets virtually representing the soil particles have been used in both the laboratory experiments and DEM simulations. The EPS beads were added to the steel pellets at 0%, 0.1%, 0.2%, 0.3%, 0.4% and 0.5% by weight. The results show that increasing the rigid grain size decreases the compressibility of the composite samples at low EPS contents. However, this impact becomes almost insignificant at very high EPS contents when rigid particles interaction is impeded.

Thermal Properties of Carbon Fiber-Reinforced Lightweight Substrate for Ecological Slope Protection

A new ecological substrate is proposed to achieve a desired electric conduction and heating to protect the slope plants from freeze injury. Expanded polystyrene (EPS), cement, carbon fiber, graphite, and raw soil are the main components of the ecological substrate. The electrical conductivity, heating efficiency, thermo-sensitivity, and heat preservation of the substrate are experimentally investigated. The result shows that the addition of carbon fiber could significantly decrease resistivity of substrate, but the effect of fiber content exceeding 3% on the resistivity of substrate becomes insignificant. Conductive fine materials (i.e., carbon fiber and graphite powder) covering the surface of EPS would result in a significant reduction of the global resistivity of non-dry substrate, but it could only slightly affect the counterpart of the completely dry substrates. The substrate could hardly be formed when the EPS content exceeds 4%. As EPS content increases, the contact surface decreases and the resistivity of the substrate increases. The peak temperature at 30 min of substrate without root is higher than that of substrate with plant roots. Nevertheless, the temperature alteration ratio below 40 °C of substrate with plant root is nearly the same as its counterpart in the substrate without roots. The resistance of the substrate with plant roots increases with the temperature. The resistance of rootless substrate decreases by the heat action of the loosely bound water. EPS particles improve the heat preservation performance of substrate, but the heat preservation performance of substrate degrades with the growth of plants.