TECHNISCHE UNIVERSITÄT MÜNCHEN München, Lehrstuhl und Prüfamt für Bau von Landverkehrswegen. Research Report No. 2362

Transcription

1 TECHNISCHE UNIVERSITÄT MÜNCHEN München, Lehrstuhl und Prüfamt für Bau von Landverkehrswegen MUNICH TECHNICAL UNIVERSITY Chair and Institute for Road, Railway and Airfield Construction Research Report No Investigations of a plastic bound superstructure (Terra Elast AG, Germany) Dieser Bericht ist die englische Fassung des Originalberichtes in deutscher Sprache. Im Zweifel hat die deutsche Fassung Gültigkeit. This is the english version of the original report in german language. In doupt the german version is valid. 1. GENERAL The company Terra Elast AG builds floor coverings and superstructures of plastic bound aggregates. Therefore crushed aggregates of different graining and Polyurethane or Epoxy as binding material will be used. To investigate the usability of a 2-layer-system for road superstructures with pro rata heavy goods vehicle traffic, in pre-tests respectively one type of surface- and baselayer was chosen from a selection of different mixtures. In the following tests relevant mechanical variables of these two mixtures were detemined. The tests were done between March and May 27 at the Institute for Road, Railway and Airfield Construction of the Technical University of Munich, Baumbachstraße 7, München.

2 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No Testing Material Remarkable for the superstructure, on which the investigation was carried out, is the acquirement to absorb water very fast. Thus there could be the possibility to build the superstructure without transversal slope, even in case of heavy rainfall. For the pretests specimens (cubes 2 x 2 cm) of six different types of base layer and three types of surface layer were sent by the client. The different types vary in binding material (Polyurethane or Epoxy), the graining of the base layer types is 16/22mm and 8/11 mm, the specimen of the surface layer are all will graining 1/3 mm. Comparable with the procedure of asphalt paving, aggregate and binding material will be mixed in a mix drum and the mixture will be places on the subbase (or frost blanket course) and compacted. Differing from this, the specimens for the tests were build in formworks and compacted manually. This was done by the client. Due to this method some of the specimens of the base layer showed an about 1 cm thick accumulation of binding material at the bottom side. According to the declaration of the client usually spare binding material penetrates into the subbase. This differ was accepted to get test specimens with even and plane specimen surfaces. Appendix 1 shows pictures of the specimens for the pretests. 3. Pretests Within the pretests the dependency of the mechanical behaviour on load frequency and repeated loading was determined at drilling cores (diameter 15 mm) of the delivered specimens. The nine different types showed varying mechanical characteristics. Thus, one type of surface course and one type of base course were selected, regarding layer thicknesses comparable with the dimensions of asphalt superstructures. The other types were not regarded any longer: Base layers with aggregate size 16/22 mm showed stiffness tending low, independent of the used binding material, likewise base layers with aggregate size 8/11 mm and binding material Polyurethane. One type of surface layer material with UVconsistent PU had a characteristic, which could be suitable for reconstruction of cracks in roads without heavy load traffic. One type of surface layer material with Epoxy got more and more rigid under repeated loading. 2 von 13

3 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No All investigated constructions were nearly independent of loading frequency in the range between 3 Hz and 3 Hz at room temperature. Based on these pre-tests the surface layer type TE 2 H2 K PU Granit WKW 1/3 PU NUV ( 1/3 PU ) and the base layer type TE 2 G2 K EP Naturschotter 8/11 EP NUV ( 8/11 EP ) were selected for a 2-layer-superstructure. 4. Test Program for evaluation of the mechanical behaviour To assure bearing capacity and fitness for purpose of the superstructure, different verification tests have to be done. Traffic loads have to be carried, but also the secure in case of thermal stresses must be guaranteed to pave the superstructure without joints. The material characteristics compressive strength, tensile strength, bending tensile strength and Young s Modulus (Modulus of Elasticity) and Poisson Value were determined at the surface layer 1/3 PU and the base layer 8/11 EP separately. Investigations regarding the bearing capacity under heavy local compressive stress were done with specimens of the 2-layer-system. For a special application on an industrial premises with heavy contact pressure under lift truck traffic (small contact area) the bearing capacity of the section near the surface was tested under stresses clear higher than under heavy load traffic. Bending tensile strength of the base layer under repeated loading was investigated in several tests (each 3 mio load cycles) with tensile stresses at the bottom side of 1,6 N/mm² (MPa) simulating loads of heavy goods vehicles [Book 26 of Announcements of the Institute for Road, Railway and Airfield Constructions of TU Munich ]. A. Compressive strength The compressive strength of cubes was tested according to the DIN EN (Testing hardened concrete Part 3: Compressive strength of test specimens). According to present experiences the dimension of the specimens was chosen big enough, at too small specimens the result of the test is involved overstate by the compressive strength of the 3 von 13

4 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No stones. According to the cited specification the velocity of loading has to be in the range of,2 to 1, N/(mm² * s). With v =,2 N/(mm² * s) the most adverse velocity was chosen, regarding possible viscose deflections. Testing the base layer (8/11mm EP), the specimens were cutted to dimension 15x15x15mm with no accumulation of binding material at the bottom side. In the tests with the surface layer (1/3mm PU) material cubes with edge length 88 mm were taken. Table 1 and 2 show the determined values. Specimen No. max. Compression load [kn] Compressive strength at cube [N/mm²] , , , , ,1 Mean Value ,2 N/mm² Table 1: Compressive strength at cubes (15 x 15 x 15 mm³) of the base layer material 8/11 EP. After the test the cracked specimens showed the common shape (see pictures in App. 2), with a combination of cracks through the stones and the binding material (mainly stone cracking). Specimen No. max. Compression load [kn] Compressive strength at cube [N/mm²] 1 96,3 12,4 2 92,6 12, 3 95,2 12,3 4 85,8 11,1 5 18, 14, Mean Value 95,6 12,3 N/mm² Table 2: Compressive strength at cubes (88 x 88 x 88 mm³) of the surface layer material 1/3 PU. Also the specimens of the surface layer had the common shape after the test (see pictures in App. 3). Because of the small aggregate size (1/3 mm PU) no statement to the nature of crack can be given. 4 von 13

5 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No B. Tensile strength In order to pave the superstructure without joints, it is necessary to reach an adequate tensile strength to resist against thermal stresses. The clearest thermal fluctuations happen at the surface. Testing the tensile strength of the surface layer material, specimens with dimension 6x6mm and a length of 2 mm were cutted. The specimen will be placed strainless in the testing device and loaded with a tensile force in longitudinal direction until it breaks. Tensile force and the strain of the specimen (with strain gauges in longitudinal and transversal direction on two opposite surfaces of the specimens) is recorded continuously. With these values Young s modulus and Poisson value can be determined. See pictures of the test in appendix 4. The test was executed with a velocity of v =,15 kn/s in steps with interim unloading. Within the 6 th loading the force was increased until the specimen broke. Because of the small aggregate size (1/3 mm PU) no statement to the nature of crack can be given. (See picture 9 in appendix 5.) The surface layer material shows a linear stress/strain-ratio, as shown in attachment 1.1 to 1.6. See table 3 for the Young s modulus (stress/strain-ratio) and the Poisson value (ratio of transversal to longitudinal strain). Test No. Young s modulus [N/mm²] Poisson value 1 614, , , , , ,22 Mean Value 5886,22 Table 3: Young s modulus and Poisson Value of the surface layer material, determined by tensile tests. 5 von 13

6 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No With the executed tests a tensile strength of the surface layer material of = 3,1 N/mm² was determined. With the determined tensile strength of = 3,1 N/mm² and adoption of a temperature independent Young s modulus of E = 59 N/mm² the secure against thermal cracking can be estimated. By setting a coefficient of thermal strain of 1 x 1-5 and a decrease of temperature of T = 3 K compared to the temperature when paving (resp. hardening of binder), a thermal stress of T = 1,8 N/mm² results. Thus, the surface layer material shows enough secure to support paving without joints. C. Bending tensile strength The RStO (german guideline for standardisation of road superstructures) demands for unbound subbase layers a modulus of subgrade reaction E V2 of 12, resp. 15 N/mm². Bound layers beyond with clear higher stiffness receive bending tensile forces, which activate radial tensile stresses at the bottom side of the base layer. In case of insufficient bending tensile strength these stresses can cause cracks, which can rise up to the surface. Therefore the time depending bending tensile strength under repeated load is very important. Superstructure of asphalt fatigue under repeated load and there stiffness decrease. Resilient materials as concrete have a permanent durability, described by a limit stress, which can be beared arbitrarily. Base layers of asphalt, which have a Young s modulus comparable with the base layer material 8/11 EP have empirical values of a time depending bending tensile strength of 2,5 N/mm² over 1 4 loadcycles (LC), 1,5 N/mm² over 1 5 LC and 1, N/mm² over 1 6 LC. Testing the bending tensile strength was done according to DIN EN (Testing hardened concrete Part 5: Flexural strength of test specimens) with base layer specimen bars 15 x 15 x 6 mm and 2-point-loading (Distance between loading points: 15 mm, Distance between bearing points: 45 mm). Tests under repeated load and determination of the bending tensile strength were done (see picture 1 in appendix 5). The tests show a bending tensile strength of 2, 5 N/mm². After the repeated load test over 3 million LC with a tensile stress of 1,6 N/mm² at the bottom side of the specimen the 6 von 13

7 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No specimens show an almost equal bending tensile strength of 2,3 N/mm², thus the repeated load did not cause a significant fatigue. Picture 11 in app. 6 shows the cracked surface of the specimen. Pro-rata cracks through stones attest a high solidity of the binding material and good adhesion with the stones. The attachments 2.1 to 2.6 show the static load (Strain and bending moment). By these values a Young s modulus of the base layer material can be determined to a mean value of 7646 N/mm² (see table 4). The attachments 3.1 to 3.3 show the changing within the repeated load test. Thus, the base layer bar does not receive a significant fatigue, only poor permanent deformations (,5 mm in the middle of the bar) can be observed, the amplitude of elastic bending (and the mechanical character) stay constant. Test No. Young s modulus [N/mm²] Mean Value 7646 Table 4: Young s modulus of the base layer material, determined under static load. The repeated load test shows, that the investigated base layer material receives no fatigue regarding the bending tensile strength and the mechanical character tends comparable to concrete (permanent durability). D. Resistance of the 2-layer-system against high contact pressure Additional to the compression stresses under a wheel load, the superstructure is charged by shear stresses under the edges of the contact area. Under high contact stresses a sudden break down can happen. To detect a sufficient resistance against high contact pressure, two specimen (5 x 5 cm) of the 2-layer-system (4 cm surface layer; 2 cm base layer) were delivered by the client (also with 1 cm accumulation of binder material at the bottom side). 7 von 13

8 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No Due to the load spreading in the specimen below the contact area, definite higher loads can be carried in this test than in compressive strength tests with cubes. The contact stresses result from the vertical load and the contact area. Under heavy load vehicles with tyres of big contact area the traffic areas are exposed by contact stresses up to 1,2 N/mm². On industrial premises with forklift traffic the contact stresses under the small wheels of forklifts are often much higher. According to informations of the client, the investigated superstructure is planned to be paved in an area, where maximum contact stresses under forklifts with rubber-wheels are 3,2 N/mm² and under plastic wheels 4,2 N/mm². To investigate these different fieldss of application, the tests were executed in load steps. In load step 3 and 4 the contact stresses were multiplied by the factor 1,2 for dynamic wheel load oscillation. In load step 1 to 3 a thin rubber mat was applicated on the contact area to simulate the situation under wheels of rubber, in load step 4 the contact area was of hard plastic. The dimensions of the load area in step 3 and 4 were approximately equal to the real situation under forklifts (due to informations of the client). Load step No. Max. contact stress [N/mm²] Number of loadcycles Dimensions of contact area [mm x mm] 1 1,2 2 million LC 9 x 9 2 2,4 1 million LC 9 x 9 3 3,8 1 million LC 12 x 3 4 5, 1 million LC 6 x 2 The repeated load test was done at a load frequency of f = 1 Hz and with lower stress at 1% of the upper stress. To simulate the subgrade reaction the specimen was placed on a rubber mat with E V2 = 12 N/mm². Before and after each load step the evenness of the specimens surface was controlled. Loss of bearing capacity would be detected by deformations of the surface. Until finishing load step 4 no relevant deformations of surface or cracks were observed. The pictures 13 to 16 in appendices 7 and 8 show the test stand and the even surface after the test. Afterwards a test was executed to investigate the viscous behaviour under a long time static load of 5, N/mm² (according to load step 4) over 3,5 days at room temperature. The 8 von 13

9 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No recorded diagram (Time/Deformation) with asymptotic developing is shown in attachment 4.1. The total deformation after 3,5 days was about,1 mm. Thus, the superstructure shows no relevant viscous creeping under high compressiv stresses at room temperature. The viscous behaviour of asphalt depends on the temperature. On hot summer days asphalt superstructures show surface temperatures up to 48 C. But this plastic bond superstructure is clearly brighter than asphalt, thus the absorption of heat is less. As per information of the client, the forklifts with hard plastic wheels and the highest contact pressure of 4,2 N/mm² are only used inside storage halls, where the maximum temperature will be clear lower than outside in summertime. To investigate possible influences of higher temperatures, the long time static test was continued with a surface temperature of 4 C, contact area 2 x 6 mm and contact stresses of 4,2 N/mm² (without dynamic factor). The heating devices were controlled by thermocouples on the surface. Addition the temperature was measured in several depths ( cm, -5 cm, -12 cm). Attachment 4.2 shows the recorded deformations and the generated heat. With a value of,14 m after 16 hours the deformations are bigger than in the test at room temperature, but the absolute value is very low. The following cooling of the specimen shows a decrease of the deformation. This might be caused by pro-rata deflection in terms of strains of the unloaded surface. The cavity of deformation does not show any cracks. Thus, the deformation is cause by redensification (past compaction) inside the surface layer. Comparing the tests at room temperature and +4 C shows, that the behaviour of the superstructure is a bit temperature dependent, but the absolute deflection is very low. Finally a test was executed, in which the contact stresses were increased continuously until the superstructure will loose its bearing capacity. This test shows, that the superstructure can bear higher pressures for short time (continuous increase with v = 2 kn/s on contact area 12 x 3 mm), than if it is a long time static load. Thus it has to be distinguished between sudden increase of deformation (increase of load not possible) and time depending creep under static load. 9 von 13

10 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No In the test with continuous increase of load, the moment as there is a sudden increase of deformation is viewed as loss of bearing capacity (see attachment 5.1 and 5.2). The determined mean value is 21,7 N/mm², which is high above the stresses under traffic. Picture 17 in appendix 9 shows the specimen with deflection cavity. In the tests concerning time dependent creep the maximum contact stress was kept for 1 minute before load relieving again. This test was done in steps, beginning with 7,5 N/mm². Attachement 6.1 to 6.5 show the recorded diagrams, thus at higher pressures a creep deformation can be observed. While relieving the load only the resilient deformations peak off. Diagram 1 shows, that the rates of viscous and resilient deformation depend on the chosen upper stress. With higher stresses the viscous pro-rata rises and the resilient pro-rata decreases, in consequence of redensification by loading. Table 5 shows the permanent deformations after load relieving, depending on the upper stress. Influence of the upper stress on resilient and creep deflections 1 9 Pro-rata of total deflection [%] Resilient pro-rata of total deflection [%] Creep pro-rata of total deflection [%] Upper stress [N/mm²] Diagram 1: Resilient and viscous creep deformation under high contact stresses. 1 von 13

11 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No Upper stress Permanent deformation after load relieving [N/mm²] [mm] 7,5,55 7,5,2 1,,134 1,,29 15,,92 15,,61 2,,215 2,,193 25, 1,495 25, 1,132 Table 5: Permanent deformation after load relieving, upper stress kept for 1 minute. Hence in case of short time load the deformations clearly rise at an upper stress of 2 N/mm². When loading for several hours, the maximum stresses are lower, with 15 N/mm² for 15 hours, the deformation increases continuously (see attachment 7.1 and 7.2). But in the test with 5 N/mm² the charge by traffic is covered confident. 5. Further investigations With the static and dynamic tests, described in this report, the specimens were charged by loads in one axle. This is suitable to determine mechanical values and fatigue behaviour of bond superstructures. The behave under rolling traffic can not be defined by these tests. A rolling wheel can cause abrations or spalling at the surface. For investigation the overroll testing device is a suitable tool to simulate the situation under rolling wheels realistic. 11 von 13

12 Chair and Institute for Road, Railway and Airfield Construction of TU Munich Report No Summary The company Terra Elast AG builds floor coverings and superstructures of plastic bound aggregates. Therefore crushed aggregates of different graining and Polyurethane or Epoxy as binding material is in use. Remarkable for the superstructure, on which the investigation was carried out, is the acquirement to absorb water very fast. Thus there could be the possibility to build the superstructure without transversal slope, even in case of heavy rainfall. To investigate the usability of a 2-layer-system for road superstructures with pro rata heavy goods vehicle traffic, in pre-tests respectively one type of surface- and baselayer was chosen from a selection of different mixtures. In the following tests relevant mechanical variables of these two mixtures were detemined. Based on these pre-tests the surface layer type TE 2 H2 K PU Granit WKW 1/3 PU NUV ( 1/3 PU ) and the base layer type TE 2 G2 K EP Naturschotter 8/11 EP NUV ( 8/11 EP ) were selected for a 2-layer-superstructure. With the executed tests a Young s modulus of the surface layer of E = 59 N/mm² and for the base layer E = 765 N/mm² was determined at room temperature. The compressive strength was determined at cubes to 12,3 N/mm² for the surface layer and 13,2 N/mm² for the base layer. Tensile tests result in a tensile strength of the surface layer of 3,1 N/mm² at room temperature. Adopting a temperature independent Young s modulus of 59 N/mm² and T = 3K, there is no risk of thermal cracking when paving the material without joints. Sufficient resistance against radial tensile stresses at the bottom side of the base layer was detected in bending tensile tests at room temperature. The base layer shows a bending tensile strength of 2,4 N/mm². Within the repeated load test over 3 million load cycles with radial tensile stresses of 1,6 N/mm² at the bottom side the specimens did not fatigue. Tests with the complete 2-layer-system (long time static tests and repeated load tests) showed, that the investigated superstructure can bear notedly high contact stresses of 5 N/mm² without significant deformation (cavity of deflection:,1 mm with asymptotic developing). In combination with higher temperatures (4 C), the deformation was a bit higher. Under short time load, stresses up to 2 N/mm² can be beared without damage. 12 von 13

13

14 Report No Attachment 1.1 3,5 3 2,5 2 1,5 1,5 Zugversuch 1 an Deckschichtbalken Tensile test No. 1 with bar 6 x 6 mm of surface layer material,1,2,3,4,5,6 Dehnung strain [o/oo] Zugspannung [N/mm²] Tensile stresses

15 Anlage Attachment ,5 3 2,5 2 1,5 1,5 Zugversuch 2 an Deckschichtbalken Tensile test No. 2 with bar 6 x 6 mm of surface layer material time [h],1,2,3,4,5,6 Dehnung strain [o/oo] Zugspannung [N/mm²] Tensile stresses

16 Anlage Attachment ,5 3 2,5 2 1,5 1,5 Zugversuch 3 an Deckschichtbalken bis Bruch Tensile test No. 3 until cracking with bar 6 x 6 mm of surface layer material,1,2,3,4,5,6 Dehnung strain [o/oo] Zugspannung [N/mm²] Tensile stresses

17 Anlage Attachment ,5 3 2,5 2 1,5 1,5 Zugversuch 4 an Deckschichtbalken Tensile test No. No. 1 with 4 with bar bar 6 x 6 mm x 6 of mm surface of surface layer material layer material,1,2,3,4,5,6 Dehnung strain [o/oo] Zugspannung [N/mm²] Tensile stresses

18 Anlage Attachment ,5 3 2,5 2 1,5 1,5 Zugversuch 5 an Deckschichtbalken Tensile test No. 5 with bar 6 x 6 mm of surface layer material,1,2,3,4,5,6 Dehnung strain [o/oo] Zugspannung [N/mm²] Tensile stresses

19 Anlage Attachment ,5 3 2,5 2 1,5 1,5 Zugversuch 6 an Deckschichtbalken bis Bruch Tensile test No. 6 until cracking with bar 6 x 6 mm of surface layer material,1,2,3,4,5,6 Dehnung strain [o/oo] Zugspannung [N/mm²] Tensile stresses

20 Anlage Attachment Dauerschwellversuch 1 an Tragschicht-Biegebalken Voreichung Repeated load test No. 1 with bending tensile bar of base layer material Static load before repeated load test,1,2,3,4,5 Dehnung strain [o/oo] Biegemoment [Nmm] Bending moment

21 Anlage Attachment Dauerschwellversuch 1 an Tragschicht-Biegebalken Nacheichung Repeated load test No. 1 with bending tensile bar of base layer material Static load after repeated load test,1,2,3,4,5 Dehnung strain [o/oo] Biegemoment [Nmm] Bending moment

22 Anlage Attachment Dauerschwellversuch 2 an Tragschicht-Biegebalken Voreichung Repeated load test No. 2 with bending tensile bar of base layer material Static load before repeated load test,1,2,3,4,5 Dehnung strain [o/oo] Biegemoment [Nmm] Bending moment

23 Anlage Attachment Dauerschwellversuch 2 an Tragschicht-Biegebalken Nacheichung Repeated load test No. 2 with bending tensile bar of base layer material Static load after repeated load test,1,2,3,4,5 Dehnung strain [o/oo] Biegemoment [Nmm] Bending moment

24 Anlage Attachment Dauerschwellversuch 3 an Tragschicht-Biegebalken Voreichung Repeated load test No. 3 with bending tensile bar of base layer material Static load before repeated load test,1,2,3,4,5 Dehnug strain [o/oo] Biegemoment [Nmm] Bending moment

25 Anlage Attachment Dauerschwellversuch 3 an Tragschicht-Biegebalken Nacheichung Repeated load test No. 3 with bending tensile bar of base layer material Static load after repeated load test,,1,2,3,4,5 Dehnung strain [o/oo] Biegemoment [Nmm] Bending moment

26 Anlage Attachment Dauerschwellversuch 1 Biegebalken Verlauf der Dehnung über die Lastspielzahl Repeated load test No. 1 with bending tensile bar of base layer material Run of strain within the repeated load test,35,3,25,2,15,1,5,e+ 5,E+5 1,E+6 1,5E+6 2,E+6 2,5E+6 3,E+6 Lastspielzahl Load Cycles min strain Dehnung min max strain Dehnung max Dehnung Strain [o/oo]

27 Anlage Attachment Dauerschwellversuch 2 Biegebalken Verlauf der Dehnung über die Lastspielzahl Repeated load test No. 2 with bending tensile bar of base layer material Run of strain within the repeated load test,5,45,4,35,3,25,2,15,1,5,e+ 5,E+5 1,E+6 1,5E+6 2,E+6 2,5E+6 3,E+6 Lastspielzahl Load Cycles min Dehnung strain min max strain Dehnung max Dehnung Strain [o/oo]

28 Anlage Attachment Dauerschwellversuch 3 Biegebalken Verlauf der Dehnung über die Lastspielzahl Repeated load test No. 3 with bending tensile bar of base layer material Run of strain within the repeated load test,9,8,7,6,5,4,3,2,1,e+ 5,E+5 1,E+6 1,5E+6 2,E+6 2,5E+6 3,E+6 Lastspielzahl Load Cycles min strain Dehnung min max strain Dehnung max Dehnung Strain [o/oo]

29 Anlage Attachment ,2 -,4 -,6 -,8 -,1 -,12 -,14 -,16 -,18 Long time static test with the 2-layer-system under vertical Dauerstandversuch stress of 5 N/mm² an (Contact zweischichtigem area: 2 Aufbau x 6 mm) at bei room 5, N/mm² temperature (Lastfläche: 2 x 6 mm) und Raumtemperatur time Zeit [h] Deformation [mm]

30 Anlage Attachment ,2 -,4 -,6 -,8 -,1 -,12 -,14 -,16 -, Zeit [h] Relative Relativbewegung deflection T (OK) T (bei -5cm) T (bei -12cm) Relativbewegung der Lastfläche [mm] Temperatur [ C] Long time static Dauerstandversuch test with the an zweischichtigem 2-layer-system Aufbau under bei (Kontaktfläche: 2 x 6 mm) vertical stress of 4,2 N/mm² (Contact area: 2 x 6 mm) und OK-Temperatur 4 C mit anschließender Abkühlung auf RT at surface temperature 4 C, followed by cooling to room temperature time [h] Relative deflection

31 Anlage Attachment ,5-1 2-layer-system Load until breakdown (Contact area: 2 x 6 mm) Zweischichtiger Oberbau Belastung bis Versagen (Kontaktfläche: 2 x 6 mm) -1,5 Relativbewegung [mm] Relative deflection [mm] -2-2,5-3 Contact Kontaktspannung stresses [N/mm²]

32 Anlage Attachment ,5-1 2-layer-system Load until breakdown (Contact area: 3 x 12 mm) Zweischichtiger Oberbau Belastung bis Versagen (Kontaktfläche: 3 x 12 mm) -1,5 Relativbewegung [mm] Relative deflection [mm] -2-2,5-3 Contact stresses Kontaktspannung [N/mm²]

33 Anlage Attachment ,5 2-layer-system Load until 7,5 N/mm² (kept for 1 minute) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 7,5 N/mm² (1 Minute Halten) Kontaktfläche "Stapler" (3 x 12 mm²) -1-1,5 Relative Relativbewegung deflection [mm] [mm] -2-2,5-3 Contact stresses Kontaktspannung [N/mm²]

34 Anlage Attachment ,5 2-layer-system Load until 1, N/mm² (kept for 1 minute) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 1, N/mm² (1 Minute Halten) Kontaktfläche "Stapler" (3 x 12 mm²) -1-1,5 Relative Relativbewegung deflection [mm] [mm] -2-2,5-3 Contact stresses Kontaktspannung [N/mm²]

35 Anlage Attachment ,5 2-layer-system Load until 15, N/mm² (kept for 1 minute) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 15 N/mm² (1 Minute Halten) Kontaktfläche "Stapler" (3 x 12 mm²) -1-1,5 Relative Relativbewegung deflection [mm] [mm] -2-2,5-3 Contact stresses Kontaktspannung [N/mm²]

36 Anlage Attachment ,5 2-layer-system Load until 2, N/mm² (kept for 1 minute) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 2 N/mm² (1 Minute Halten) Kontaktfläche "Stapler" (3 x 12 mm²) -1-1,5 Relative Relativbewegung deflection [mm] [mm] -2-2,5-3 Contact stresses Kontaktspannung [N/mm²]

37 Anlage Attachment ,5 2-layer-system Load until 25, N/mm² (kept for 1 minute) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 25 N/mm² (1 Minute Halten) Kontaktfläche "Stapler" (3 x 12 mm²) -1-1,5 Relative Relativbewegung deflection [mm] [mm] -2-2,5-3 Contact stresses Kontaktspannung [N/mm²]

38 Anlage Attachment ,5 2-layer-system Load until 15, N/mm² (kept for 15 hours) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 15 N/mm² (15 Stunden Halten) Kontaktfläche "Stapler" (3 x 12 mm²) -1-1,5-2 Relative Relativbewegung deflection [mm] [mm] -2,5-3 Contact stresses Kontaktspannung [N/mm²]

39 Anlage Attachment ,5-1 -1,5-2 -2,5 2-layer-system Load until 15, N/mm² (kept for 15 hours) (Contact area Zweischichtiger "fork lift": 3 Oberbau x 12 mm) Belastung bis 15 N/mm² (15 Stunden Halten) Kontaktfläche "Stapler" (3 x 12 mm²) time Zeit [h] [h] Deformation Einsenkung [mm]

40 Report No Appendix 1 Picture 1: Specimens cubes 2 x 2 cm of three surface-layer- and six base-layer-types of plastic bond aggregates. Picture 2: Drilling cores of the two types, which were chosen for further investigations 1/3 mm PU and 8/11 mm EP.

41 Report No Appendix 2 Picture 3: Cube of the base layer material (Edge length: 15 mm) while testing the compressive strength. Picture 4: Cracked specimen after the test. The cracked surface shows mainly cracks through stones.

42 Report No Appendix 3 Picture 5: Characteristic shape of the cracked specimen of surface layer material (Edge length 88 mm). Picture 6: The stones in the centre look pulverised. Because of the fine-grained aggregate 1/3 mm the kind of crack can t be described more precisely.

43 Report No Appendix 4 Picture 7: Testing device of the tensile strength test at surface layer material. Picture 8: Crack due to tensile stresses near the fixed support (change of diameter). At this position the change of diameter causes additional stresses. Thus, the determined tensile strength is with excess charge.

44 Report No Appendix 5 Picture 9: Cracked surface of the bar after the tensile test. Picture 1: Testing device of the bending tensile test. The specimen is charged by 2-pointloading.

45 Report No Appendix 6 Picture 11: Cracked surface of the bar after bending tensile test, mainly with cracks through stones. Picture 12: Specimen bars with applicated strain gauges after the test.

46 Report No Appendix 7 Picture 13: Testing device of the repeated load compressive test with complete 2-layersystem. The small contact area (2 x 6 mm) with a rigid plastic pad simulates the charge of the superstructure by forklifts with high contact pressure and plastic wheels. Picture 14: Contact area (3 x 12 mm) with rubber mat, simulating forklifts with tyres of rubber.

47 Report No Appendix 8 Picture 15: Long time static test with additional high temperature charge. Picture 16: Surface of the specimen with marginal deformation cavity (,1 mm) after the long time static test.

48 Report No Appendix 9 Picture 17: Cracked surface after continuous rising of the contact stresses until breakdown. The cavity is sharp-edged.