DIN 18218-2010 Pressure of fresh concrete on vertical formwork《新浇混凝土对垂直模板的压力》.pdf

1、January 2010DEUTSCHE NORM Normenausschuss Bauwesen (NABau) im DINDIN-SprachendienstEnglish price group 11No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale

2、for German Standards (DIN-Normen).ICS 91.080.40!$mQ“1745646www.din.deDDIN 18218Pressure of fresh concrete on vertical formworkEnglish translation of DIN 18218:2010-01Frischbetondruck auf lotrechte SchalungenEnglische bersetzung von DIN 18218:2010-01Pression de bton frachement malax sur des coffrages

3、 verticauxTraduction anglaise de DIN 18218:2010-01SupersedesDIN 18218:1980-09www.beuth.deDocument comprises pages1904.11 DIN 18218:2010-01 A comma is used as the decimal marker. Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms, definitions and symbols.4 3.1 Terms and definitions .4

4、 3.2 Symbols 6 3.3 Subscripts 6 4 Fresh concrete pressure.6 4.1 General6 4.2 Design value of fresh concrete pressure 6 4.3 Distribution of fresh concrete pressure over the height of the formwork.7 4.4 Determination of the characteristic value of the maximum fresh concrete pressure 8 5 Parameters aff

5、ecting the magnitude of fresh concrete pressure.9 5.1 General9 5.2 End of setting.10 5.3 Temperature .10 5.4 Fresh concrete density .11 5.5 Compaction 11 5.6 Admixtures and additives .11 5.7 Vibrations .12 5.8 Reinforcement12 Annex A (normative) Determination of setting times by the “knead bag” meth

6、od13 A.1 General13 A.2 Apparatus .13 A.3 Sampling and test procedure .13 A.4 Test report 14 Annex B (normative) Diagrams to determine the maximum value of lateral fresh concrete pressure15 2 DIN 18218:2010-01 Foreword This document has been prepared by Working Committee NA 005-07-11 AA Bauausfhrunge

7、n of the Normenausschuss Bauwesen (Building and Civil Engineering Standards Committee). The new edition of the standard was published because of the need to incorporate concrete of consistency classes F5, F6 and self-compacting concrete (SCC), as no provisions covering these types of concrete existe

8、d up to this point in time. The specifications have been developed on the basis of scientific publications and the results of tests on the pressure of fresh concrete on vertical formwork. Amendments The standard differs from DIN 18218:1980-09 as follows: a) the terms and definitions have been brough

9、t into line with technical developments, and the terminology has been adapted to correspond to that used in the reference standards; b) loads are determined using the concept of partial safety factors; c) the influence of fresh concrete temperatures is taken into account; d) the influence of concret

10、e compaction (vibration) is taken into account; e) the method used to determine the pressure of fresh concrete has been amended, particularly with regard to consistency classes F5, F6 and SCC; f) test methods to determine the end of setting of concrete have been specified. Previous editions DIN 1821

11、8: 1980-09 3 DIN 18218:2010-01 1 Scope This standard is intended to be used to determine the fresh concrete pressure on vertical formwork by concrete according to DIN EN 206-1 and DIN 1045-2, and by self-compacting concrete (SCC) according to DAfStb-Richtlinie “Selbstverdichtender Beton” (SCC Code o

12、f practice issued by the German Reinforced Concrete Committee) with a maximum size of aggregate of 63 mm. The fresh concrete pressure established according to this standard is the most important criterion governing the design of vertical formwork and formwork that deviates from the vertical by up to

13、 5. Deviations from the specifications of this standard are permitted if a more precise verification is made on the basis of calculation and/or empirical testing. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, o

14、nly the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. DIN 1045-2, Concrete, reinforced and prestressed concrete structures Part 2: Concrete Specification, properties, production and conformity Application rules for DI

15、N EN 206-1 DIN 4235-1:1978-12, Compacting of concrete by vibrating Vibrators and vibration mechanics DIN 4235-2:1978-12, Compacting of concrete by vibrating Compacting by internal vibrators DIN 4235-3, Compacting of concrete by vibrating Compacting by external vibrators during the manufacture of pre

16、cast components DIN 4235-4, Compacting of concrete by vibrating Compacting of in-situ by formwork vibrators DIN EN 206-1:2001-07, Concrete Part 1: Specification, performance, production and conformity; German version EN 206-1:2000 DIN EN 480-2, Admixtures for concrete, mortar and grout Test methods

17、Part 2: Determination of setting time DIN EN 12350-5, Testing fresh concrete Part 5: Flow table test DIN EN 12812, Falsework Performance requirements and general design DAfStb-Richtlinie Selbstverdichtender Beton (SVB-Richtlinie) (DAfStb Code of practice on self-compacting concrete)1)3 Terms, defini

18、tions and symbols 3.1 Terms and definitions For the purposes of this document the following terms and definitions apply. 3.1.1placing temperature Tc,placingtemperature of the fresh concrete directly after placing (in the formwork) 1) Obtainable from Beuth Verlag GmbH, 10772 Berlin. 4 DIN 18218:2010-

19、01 NOTE The placing temperature can be deduced from the temperature of the fresh concrete at the time of its handover on site and from the prevailing ambient conditions. 3.1.2 depth of penetration of internal vibrator hvdifference in height between the surface of the fresh concrete and the lower end

20、 of the internal vibrator 3.1.3 end of setting tEtime between the first addition of water for making the concrete and the point in time at which the concrete is fully set NOTE The end of setting of the fresh concrete tE can be determined by the Vicat penetration method specified in DIN EN 480-2 usin

21、g mortar that is sieved from the concrete using a sieve of 4 mm aperture size. The end of setting may also be approximated to tE= 1,25 tE,knead, where tE,kneadis the end of setting according to the “knead-bag test” (see Annex A). 3.1.4 fresh concrete mixture of cement, aggregate and water (and, wher

22、e required, admixtures and additions), that has not yet set or hardened and that still requires the support of formwork in order to retain its dimensional stability 3.1.5 lateral fresh concrete pressure hlateral pressure caused by fresh concrete acting on the surface of formwork 3.1.6 fresh concrete

23、 density cdead weight divided by the volume of the fresh concrete after compaction 3.1.7 hydrostatic pressure head hsdifference in height between the surface of the fresh concrete and the point at which the fresh concrete pressure reaches the value hk,max3.1.8 consistency measure of the deformabilit

24、y and flowability of the fresh concrete NOTE The consistency of fresh concrete is evaluated in accordance with DIN EN 206-1 or DIN 1045-2 by means of consistency classes or flow classes. The concrete is classified into classes F1, F2, F3, F4, F5 or F6 or as self-compacting concrete. The flow table t

25、est according to DIN EN 12350-5 is used. 3.1.9 reference temperature Tc,Reffresh concrete temperature used to determine the end of setting tE3.1.10 placing rate v rise in level of the fresh concrete surface during pouring related to time 5 DIN 18218:2010-01 3.2 Symbols ds diameter of reinforcement h

26、 height of concrete hEheight of concrete at end of setting tEhshydrostatic pressure head hvdepth of penetration of internal vibrator H overall height of building part to be poured t time tEend of setting T temperature v placing rate (pouring rate) density, partial safety factor cdensity of fresh con

27、crete Fpartial safety factor of an action stress h lateral fresh concrete pressure hd design value of lateral fresh concrete pressure hk characteristic value of lateral fresh concrete pressure 3.3 Subscripts c fresh concrete d design value E end of setting of fresh concrete placing moment in time at

28、 which the fresh concrete is placed in the formwork F action, force h lateral hydr hydrostatic pressure method taking into account the density of fresh concrete knead “knead bag” method k characteristic value max maximum value Ref reference value 4 Fresh concrete pressure 4.1 General A distinction s

29、hall be made between the absolute value of fresh concrete pressure and the distribution of the fresh concrete pressure over the height of the formwork. In this standard, the fresh concrete pressure is stated as the characteristic value of the action hk. When designing formwork constructions includin

30、g their supports and anchoring, the fresh concrete pressure shall be taken to be a static load. 4.2 Design value of fresh concrete pressure The design of formwork and falsework including anchoring shall be based on the design value of the fresh concrete pressure hd= F hk. The partial safety factor F

31、can be taken from DIN EN 12812. For the analyses at ultimate limit state the factor is F= 1,5 for unfavourable actions. A partial safety factor of F= 1,0 shall be used in cases where the fresh concrete pressure is assumed to act favourably. 6 DIN 18218:2010-01 4.3 Distribution of fresh concrete pres

32、sure over the height of the formwork In the ultimate limit state, the formwork of height H shall be designed assuming the most unfavourable load position in the pressure distribution diagram shown in Figure 1 as a function of the level of the concrete. The distribution of the fresh concrete pressure

33、 over the height hE= v tEshall be taken to be as in Figure 1. Where the height H of the formwork is greater than hEthe fresh concrete pressure distribution in Figure 1 is a moving load that changes upwards over the height of the formwork. A suitable load diagram shall be used for the analysis of for

34、mwork deformation at the serviceability limit state. Key 1 fresh concrete 2 set (hardened) concrete 3 upper level of concrete 4 hydrostatic fresh concrete pressure 5 F-times hydrostatic fresh concrete pressure Figure 1 Distribution of fresh concrete pressure over the height of the formwork 7 DIN 182

35、18:2010-01 4.4 Determination of the characteristic value of the maximum fresh concrete pressure Characteristic values of the maximum possible fresh concrete pressure hk,maxfor various placing rates and consistency classes can be calculated on the basis of the information given in Table 1. In additio

36、n, the characteristic value of the maximum fresh concrete pressure can be taken from the diagrams in Figures B.1 to B.5. Each diagram is based on a specified end of setting tEfor the fresh concrete. The equations in Table 1 and Figures B.1 to B.5 are based on the following conditions: a) the fresh c

37、oncrete density cis 25 kN/m3. Where it has a different value, 5.4 shall be taken into account; b) the actual end of setting of the fresh concrete placed into the formwork does not exceed tE. c) fresh concrete of consistency classes F1, F2, F3, F4, F5 and F6 is compacted using internal vibrators; d)

38、the formwork is watertight (e.g. large-area formwork made of veneer plywood); e) the mean placing rate v of concrete of consistency classes F1, F2, F3, F4 is not more than 7,0 m/h at any point; f) the concrete is poured in opposite direction to the rise in level (i.e. it is placed from the top). If

39、the concrete is placed from the bottom (such as when pumps are used for placing SCC) hk,maxshall be assumed to be at least the hydrostatic fresh concrete pressure at the feed location. The maximum difference in height between the feed location and the upper level of the concrete should at no time be

40、 more than 3,5 m. The concrete shall be placed at a steady rate until it reaches its maximum level. Placing of the entire building part should not take longer than 60 min, and any interruptions to the concreting process should not be longer than 10 min, except where there will be no significant chan

41、ges in the rheological properties of the fresh concrete during placing, in which case longer interruptions and greater differences in height are possible. Subclause 5.3.2 shall be taken into account in cases where the temperature at which the fresh concrete is placed, Tc,placing, deviates from the r

42、eference temperature Tc,Refaccording to 3.1.9 by more than 1 K. The end of setting of the fresh concrete is determined on the basis of its composition (w/c value, cement type, additives, admixtures) and the temperature conditions (fresh concrete and ambient temperature combined with the type of form

43、work) at the time of placing, and is to be calculated during the initial testing (see 3.1.3, 5.2 and Annex A). The following information regarding the end of setting can be used to indicate the expected values. In the case of concrete with a strength development classified as “rapid” in accordance w

44、ith DIN EN 206-1:2001-07, Table 12, at a temperature over +15 C, or concrete classified as “medium” at a temperature over +20 C, the end of setting can be assumed to be tE= 5 h provided the mix does not contain any retarders. Where concrete is of “rapid” strength development at a temperature over +1

45、0 C, “medium” at a temperature over +15 C, or “slow” at a temperature over +20 C, the end of setting may be assumed to be tE= 7 h if the other conditions are the same. Subclause 5.3 shall be referred to for deviations between the reference temperature (Tc,Ref) and the temperature of the concrete dur

46、ing setting. The estimate of the setting time is based on concrete with a strength class of at least C20/25. A reliable estimation of the end of setting cannot be made for concrete of “very slow” strength development, at lower concrete temperatures, or where retarding admixtures are used. It is to b

47、e noted that the addition of superplasticizers can considerably retard the setting procedure, particularly in the case of highly flowable concrete (i.e. concrete of consistency classes F5, F6, or SCC). 8 DIN 18218:2010-01 Table 1 Characteristic values of maximum lateral fresh concrete pressure (wher

48、e concrete is placed in opposite direction to the rise in level) 1 2 1 Consistency class Maximum lateral fresh concrete pressure when placed in opposite direction to the rise in level (from above) hk,maxkN/m22 F1 ( ) 25215 + K1v 3 F2 ( ) 251910 + K1v 4 F3 ( ) 251814 + K1v 5 F4 ( ) 251717 + K1v 6 F5 303025 + K1v 7 F6 303825 + K1v 8 SCC 303325 + K1v Where v is the placing rate (pouring rate) in m/h; K1 is the factor taking into account the setting behaviour according to Ta