GEOTECHNICAL REPORT AT 29 PETRIES ROAD, WOODEND. KIRK ROBERTS CONSULTING ENGINEERS LTD

Transcription

1 GEOTECHNICAL REPORT KIRK ROBERTS CONSULTING ENGINEERS LTD AT 29 PETRIES ROAD, WOODEND. P a g e 1 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

2 SUMMARY The proposed subdivision of 29 Petries Road, Woodend has been assessed for liquefaction risk to meet the interim minimum requirements for geotechnical assessment of liquefaction for land subdivision development. The initial geotechnical investigation completed by Davie Lovell Smith Ltd consisted of Machine auger boreholes to between 3. to 6.5 m depth and terminated in silty and sandy gravel. Further testing involving Cone Penetrometer tests was carried out over the site and encountered thin layers of gravel from 4.5m to 14.8 m and interbedded silt and sand. Reference to ECAN borelogs confirm the gravel layer at CPT4 location would extend to at least 35 m with possible thin inclusions of silt and sand to about 31m. Liquefaction assessment based on the method by NCEER predicts ground damage of 5 to 65 mm for a 5 year ultimate limit state (ULS) earthquake event. No liquefaction settlement predicted for a 25 year serviceability limit state (SLS) event. Cone Penetrometer Test CPT4 achieved penetration to 14.8 m depth with predicted liquefaction settlement of 65 mm, with perhaps a margin of error of +- 5%. Therefore, liquefaction settlement of 33 to 98 mm is predicted over the entire site and is consistent with Technical Category 2 classification in accordance with the DBH guidelines. Therefore, we recommend the site should be classified as Technical Category 2 for design of shallow foundations on liquefaction prone sites. In our opinion, there are no other geotechnical hazards identified which could otherwise prevent a subdivision consent being granted in accordance with section 16 of the Resource Management Act P a g e 2 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

3 9 th March 212 To Davie Lovell-Smith Ltd 79 Cambridge Terrace, PO Box 679 Christchurch 814 Attention Gordon Peebles JOB NO /G Dear Gordon 1. INTRODUCTION RE Geotechnical Assessment of 29 Petries Road Subdivision, Woodend We have been instructed by you to provide a geotechnical assessment of for the above mentioned site to meet the interim minimum requirements for geotechnical assessment of liquefaction for land subdivision development and also provide a statement of professional opinion for suitability of the land for residential development in accordance with local council requirements. 2. SITE DESCRIPTION The setting is a parcel of land located on the south side of Petrie Road in Woodend. The site is undeveloped and is covered by dense grass and established trees. This site is currently used by the owner for grazing horses. 3. SITE GEOLOGY The anticipated subsurface soil profile is this area of Christchurch consists of alluvial sand silt overbank deposits overlying shallow gravel of the Springston Formation 1 and deeper sand deposits of the Christchurch Formation 1 4. GEOTECHNICAL INVESTIGATION Davie Lovell-Smith s geotechnical assessment completed 17 October 211 consisted of seven machine auger borehole taken to between 3. to 6.5 m depth and terminated in silty and sandy gravel. All Machine auger holes where completed under supervision of Davie Lovell-Smith Ltd. Further testing completed by McMillan Drilling Ltd on 2 th February 212 consisted of seven Cone Penetrometer Tests taken to effective refusal for liquefaction assessment over the site. Refer to Appendix B for ECAN borelogs and Machine auger boreholes. 5. SUBSURFACE CONDITIONS Reference to several ECAN borehole logs located close to the site subject property provide subsurface soil profiles to between m. The boreholes indicate the top 4 to 11 m thick layer of soil consists of clayey silt and gravel of the Springston Formation overlying course to fine sand to approximately 17 m of the Christchurch Formation overlying gravel to at least 3 m of the Riccarton Formation. 1 Geology of the Christchurch Urban Area; L.J Brown and J.H.Weeber,1992. P a g e 3 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

4 The CPT tests met refusal at 4.5 to 14.6 m in dense gravel. The variability in effective refusal depths at CPT1 to CPT7 indicates the variable depth of the thin gravel layer inclusions bounded within the interbedded layers of silt and sand to14.6 m depth. At CPT2 and 4, the Riccarton gravel layer is encountered at 14.2 to 14.8 m respectively and is consistent with the general subsurface soil conditions encountered at the ECAN borelogs in Appendix B. 6. GROUND WATER TABLE The seven machine auger boreholes indicated a water table at 3. m below existing ground level.reference to the ECAN borehole logs in Appendix B indicate a water table at 2.5m to 3.7m below ground level (bgl). Therefore an average water table of 2.5 m bgl will be adopted over the entire site for the purpose of liquefaction assessment. 7. LIQUEFACTION ASSESSMENT 7.1 Input Ground Motion for Liquefaction There is still some uncertainty over which input ground motion should be used for calculating the cyclic stress ratio (CSR). Recent amendments to NZS has increased the peak ground acceleration (PGA) by 36 % within the Christchurch area based on a revised hazard factor of Z=.3 (previously Z=.22). The resulting peak ground acceleration is.34g for a 5 year earthquake event. Recent research from Geological Nuclear Sciences (GNS) has identified that Christchurch is susceptible to smaller magnitude earthquakes that produce higher peak ground accelerations over shorter periods compared to the recently adjusted response spectra from NZS The peak ground accelerations GNS is estimating for liquefaction assessments for Christchurch, with an average return period of 5 years, are much higher than those from NZS 117. GNS estimate a PGA of.49g for a 5 year event (ULS) and.15g for a 25 year event (SLS). GNS indicate that the 5 year PGA value is still being influenced by the current aftershock sequence and based on their hazard model studies this value will reduce to a long term value of.43g after about 15 years. When one considers the recent earthquake events experienced in Christchurch, the Darfield earthquake on 4 September 21 produced ground motions ranging from.17g to.31g over the wider Christchurch area and about.16g -.25g in the CBD area. This suggests that an average PGA value of.21g would be appropriate for the Christchurch CBD area. Results from probabilistic seismic hazard analysis completed by GNS suggest that a M w =8. Alpine Fault with a return period of about 3-4 years will produce PGA s in the range of.6g and.17g for a site class C and allows for ground motion amplification due to local site effects. GNS Ltd has indicated that the anticipated ground damage in the Christchurch area due to the Alpine Fault would be similar to the ground damage experienced from the 4 September 21 earthquake. Even though the characteristics of both events would be different, i.e. longer duration shaking from the Alpine fault verses shorter duration shaking from the Greendale fault, the combined effect of duration of shaking and PGA from the respective faults would be expected to produce similar ground damage.therefore one can conclude that ground motion of about.17g could occur within the Christchurch CBD area due to an M w =8. Alpine Fault event. Table 7.1 below summarises the different peak ground accelerations either calculated by the updated seismic hazard model (in the case of GNS and NZS and the Alpine Fault) or from measured PGA values resulting from the Greendale Fault (Darfield earthquake event). P a g e 4 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

5 PGA ULS PGA SLS NZS (Mw =7.5).34g.11g GNS.43g.15g Greendale Fault (Mw = 7.1) g - Alpine Fault (Mw =8.).6-.17g - Table 7.1 Peak ground accelerations (PGA) expressed as a percentage of gravity (g). The magnitude of the earthquake is indicated in brackets (). For the purpose of liquefaction prediction, a PGA value of.34g shall be used to calculate the cyclic stress ratio (CSR) for a 5 year earthquake event in accordance with NZS for the Ultimate Limit State (ULS). 7.2 Liquefaction Interpretation Liquefaction hazard has been identified beneath this site with strong earthquake shaking, based on the cyclic stress method of analysis by NCEER 2. The prediction is for potential liquefaction of the thin loose sand lenses and silty sands between 2.5 m to 14.6 m at CPT1 and CPT7 respectively. Liquefaction is predicted to total approximately.15 m to 2.17 m thickness at CPT1 to CPT7. Total ground settlement prediction is for 5 mm to 65 mm for an ultimate limit state event (ULS) event. No settlement is predicted for a Serviceability Limit State (SLS) event. The cyclic stress method of analysis adopted by the NCEER is known to be conservative based on historical case studies of liquefaction sites and it s over prediction of liquefaction in deeper soils. Combined with the uncertainties associated with estimating liquefaction settlement based on Isihara & Yoshimina s method, the settlement estimates below are therefore considered to be conservative. Total thickness and settlement of liquefiable sands to m at CPT1 to CPT7 test locations and for the estimated return periods are given below in Table 7.2(a) and Table 7.2(b) respectively. The estimated settlements are considered to be conservative based on the reasoning s explained in the previous section. For an importance level 2 building with a serviceability limit state return period of 25 years, liquefaction damage beneath the site is not critical. The ultimate limit state return period of 25 and 5 years is critical for liquefaction damage caused by ground settlement. Liquefaction potential is predicted for earthquake return periods greater than 25 years. Table 7.2(a) Thickness of Liquefiable layers to m depth, for a M7.5 earthquake. Test Location Total Liquefiable Layer Thickness (m) 25 year Return Period 5 year Return Period CPT 1.19 CPT CPT CPT CPT 5.55 CPT 6.15 CPT National Centre of Earthquake Engineering and Research Workshop, P a g e 5 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

6 Table 7.2(b) Thickness of Liquefiable settlement to m depth, for a M7.5 earthquake. Test Location Total Settlement (in mm) 25 year Return Period 5 year Return Period CPT 1 5 CPT 2 54 CPT 3 56 CPT 4 65 CPT 5 14 CPT 6 6 CPT 7 21 As previously mentioned, liquefaction induced ground settlement has been assessed using the method developed by Isihara & Yoshimina, 1992; for the shallow CPT soil profiles as shown in Table 7.2(a). The method is largely empirical and approximate only, with perhaps a 5% margin of error from the assessed ground settlements in table 7.2(b). 8. ASSESSMENT AGAINST RMA Section 16 the RMA states inter alia 1. a consent authority may refuse subdivision consent, or may grant subdivision consent subject to conditions, if it considers that (a) the land in respect of which a consent is sought, or any structure on the land, is or is likely to be subject to material damage by erosion, falling debris, subsidence, slippage, or inundation from any source; or (b) any subsequent use that is likely to be made of the land is likely to accelerate, worsen, or result in material damage to the land, other land, or structure by erosion, falling debris, subsidence, slippage, or inundation from any source; (c) sufficient provision has not been made for legal and physical access to each allotment to be created by the subdivision. The site is not susceptible to inundation and rock fall is unlikely given the site is flat and is located within an established rural area of Canterbury. Section 7. of this report considers the liquefaction- induced ground damage, in which only moderate liquefaction settlement of 5 to 69 mm is predicted over the site for a 5 year earthquake event. Therefore, we conclude there is no reason to refuse subdivision consent to clause 16 (a), based on rock fall, soil inundation or liquefaction hazard. Any proposed development will have to comply with relevant legislation, codes and standards. For example, fills would have to be constructed at safe slopes and cuts would have to be excavated to provide stable slopes. Any potential location for a future dwelling on the proposed allotments would not require significant fill or cut earthworks. In our opinion therefore, Clause 16 1(b) would not provide grounds for refusing a sub divisional consent. Section 16 1(c) is not relevant to a geotechnical appraisal and therefore has not been considered in this report. P a g e 6 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

7 9. CONCLUSIONS An initial geotechnical investigation completed by Davie Lovell Smith Ltd consisted of Machine auger boreholes to between 3. to 6.5 m depth and terminated in silty and sandy gravel. Further testing involving Cone Penetrometer tests encountered thin layers of gravel from 4.5m to 14.8 m. The soil profile is consistent with the general subsurface soil conditions encountered at the ECAN borelogs in Appendix B. Liquefaction assessment based on the method by NCEER predicts ground damage of 5 to 65 mm for a 5 year ultimate limit state (ULS) earthquake event. No liquefaction settlement predicted for a 25 year serviceability limit state (SLS) event. The predicted liquefaction settlement for a 5 year event varies considerably over the site which can be attributed to the variable CPT refusal depths due to the underlying thin gravel layers. Cone Penetrometer Test CPT4 achieved penetration to 14.8 m depth with predicted liquefaction settlement of 65 mm, with perhaps a margin of error of +- 5%. Accordingly, liquefaction settlement of 33 to 98 mm is predicted over the site and is consistent with Technical Category 2 land classification in accordance with the DBH guidelines for design of foundations on liquefaction prone land. In our opinion, there are no other geotechnical hazards identified which could otherwise prevent a subdivision consent being granted in accordance with section 16 of the Resource Management Act We are prepared to submit a professional statement of opinion to satisfy subdivision consent application in accordance section 16 of the RMA. P a g e 7 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

8 1. DISCLAIMER This report has been prepared solely for the benefit of Kevin O Donnell, Davie Lovell Smith Ltd and the Waimakariri District Council. No liability is accepted by this company or any employee of this company with respect to its intended use by any other person or persons. This disclaimer shall apply notwithstanding that the report may be made available to other persons for an application for permission or approval to fulfill a legal requirement. The subsurface soil conditions and the interpretations reported are those identified at the locations of the investigations at the time of the investigation and are subject to the limitations of the investigation methods. The CPTresults represent only a small test sample of the total subsurface soils. Soil conditions may vary between the CPT locations and interpretation of the soil information and test results must take into account the spacing and plan location of the CPT s. During construction Kirk Roberts Consulting Engineers Ltd cannot assume responsibility for unexpected variations in ground conditions or the actions of contractors which may compromise the content of this report. If subsurface conditions encountered on the site during construction appear to vary from those inferred from the information contained in this report, Kirk Roberts Consulting Engineers Ltd requests that it be notified immediately. This report is only valid for the proposal as outlined in the introduction and the information and interpretation of the content in this report may not be relevant if the proposed development is altered in anyway. Yours Sincerely, Kirk Roberts Consulting Engineers Ltd S. ROBERTS Director CPEng, MIPENZ,IntPE(NZ) Practicing as a Geotechnical Engineer P a g e 8 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

9 APPENDIX A Subdivision location Plan by Davie Lovell Smith Ltd. P a g e 9 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

10 ( 25. ) ( 16.5 ) ( 14. ) m² 9 681m² 1 6m² 11 6m² m² Road to Vest in 23 Waimakariri District Council m² 74m² 4 712m² 8 628m² 7 723m² 5 63m² 6 77m² m² 613m² 617m² 6m² 6m² ( 14. ) 2637m² PETRIES ROAD m² m² 2 624m² m² 18 76m² AMENDMENT DATE DESCRIPTION 1) Areas and dimensions are subject to final survey and deposit of plans. 2) Service easements to be created as required. 3) This plan has been prepared for subdivision concept purposes only. No liability is accepted if the plan is used for any other purpose. 4) Roading & planting detail is indicative only. Woodend East Ltd Petries Road - Woodend Proposed Subdivision of Pt Lot 1 DP Proposed Subdivision 175@A3 November 211 J\17796\C17796 Concept.dwg C R

11 APPENDIX B ECAN Borelogs Machine Auger holes completed by Davie Lovell Smith Ltd P a g e 1 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

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25 APPENDIX C CPT Location Plan CPT results from McMillan Drilling Ltd Liquefaction assessment for 25year (SLS) and 5 year (ULS) events P a g e 11 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

26 APPENDIX C CPT Location Plan CPT results from McMillan Drilling Ltd Liquefaction assessment for 25year (SLS) and 5 year (ULS) events CPT Test Locations at 29 Petries Road, Woodend. P a g e 11 KIRK ROBERTS CONSULTING ENGINEERS LTD GEOTECHNICAL REPORT 29 PETRIES ROAD, WOODEND ISSUE 1 Date 9 th March 212 Job

27 CPT ANALYSIS NOTES Soil Type Interpretation using chart of Robertson & Campanella (1983). This is a simple but well proven interpretation using cone tip resistance (q C ) and friction ratio (f R ) only. No normalisation for overburden stress is applied. Cone tip resistance measured with the piezocone is corrected with measured pore pressure (u C ). sand (and gravel) silt-sand silt clay-silt clay peat Liquefaction Screening The purpose of the screening is to highlight susceptible soils, that is sand and siltsand in a relatively loose condition. This is not a full liquefaction risk assessment which requires knowledge of the particular earthquake risk at a site and additional analysis. The screening is based on the chart of Shibata and Teparaksa (1988). high susceptibility medium susceptibility low susceptibility High susceptibility is here defined as requiring a shear stress ratio of.2 to cause liquefaction with D 5 for sands assumed to be.25 mm and for silty sands to be.5 mm. Medium susceptibility is here defined as requiring a shear stress ratio of.4 to cause liquefaction with D 5 for sands assumed to be.25 mm and for silty sands to be.5 mm. Low susceptibility is all other cases. Relative Density (D R ) Based on the method of Baldi et. al. (1986) from data on normally consolidated sand. Undrained Shear Strength (S U ) Derived from the bearing capacity equation using S U = (q C σ VO )/15.

28 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT1 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT1 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

29 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT1 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

30 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT2 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT2 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

31 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT2 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

32 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT3 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT3 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

33 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT3 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

34 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT4 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT4 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

35 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT4 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

36 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT5 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT5 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

37 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT5 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

38 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT6 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT6 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

39 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT6 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

40 Tip resistance (MPa) Friction ratio (%) Inclination ( c) DEPTH IN METERS BELOW GROUND LEVEL CLIENT LOCATION DATE OPERATOR REMARK 1 REMARK JOB # 9964 H.Pardoe TEST # CPT7 Kirk Roberts Consulting Engineers Ltd 29 Petries Road, Christchurch CPT7 Effective Refusal 12 High St Southbridge CANTERBURY NZ Ph Fax

41 PIEZOCONE PENETROMETER TEST (CPTU) INTERPRETIVE REPORT q c (MPa) Type Liq Dr (%) Su (KPa) Friction Ratio (%) Job No 9964 Date CPT No CPT7 Operator H Pardoe Project Kirk Roberts Consulting Engineers Ltd Remark Effective Refusal Location 29 Petries Road, Christchurch

42 depth (m) M=7.5 PGA=.11 25year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT1 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio Cyclic Resistance Ratio_CPT

43 depth (m) M=7.5 PGA=.11 25year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT2 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio Cyclic Resistance Ratio_CPT

44 depth (m) M=7.5 PGA=.11 25year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT3 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 8 Cyclic Resistance Ratio_CPT

45 depth (m) M=7.5 PGA=.11 25year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT5 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 9 Cyclic Resistance Ratio_CPT

46 depth (m) M=7.5 PGA=.11 25year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT6 Cyclic Resistance Ratio stress Ratio Cyclic Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 7 Cyclic Resistance Ratio_CPT

47 depth (m) M=7.5 PGA=.11 25year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT7 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio Cyclic Resistance Ratio_CPT

48 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petrie Road,Woodend Job No Client 29 Petrie Road,Woodend Hole No CPT1 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 12 Cyclic Resistance Ratio_CPT

49 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petrie Road,Woodend Job No Client 29 Petrie Road,Woodend Hole No CPT2 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 12 Cyclic Resistance Ratio_CPT

50 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petrie Road,Woodend Job No Client 29 Petrie Road,Woodend Hole No CPT3 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 12 Cyclic Resistance Ratio_CPT

51 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petrie Road,Woodend Job No Client 29 Petrie Road,Woodend Hole No CPT4 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) ` Cyclic Stress Ratio Cyclic Resistance Ratio_CPT

52 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT5 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 9 Cyclic Resistance Ratio_CPT

53 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT6 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio 8 9 Cyclic Resistance Ratio_CPT

54 depth (m) M=7.5 PGA=.34 5year Return Period Date Mar-12 Project 29 Petries Road Job No Client 29 Petries Road Hole No CPT7 Cyclic Resistance Ratio Cyclic stress Ratio Factor of Safety Liquefiable layers Ground settlement (mm) Cyclic Stress Ratio Cyclic Resistance Ratio_CPT

55 APPENDIX I. STATEMENT OF PROFESSIONAL OPINION ON THE SUITABILITY OF LAND FOR BUILDING CONSTRUCTION ISSUED BY KIRK ROBERTS CONSULTING ENGINEERS LTD (Engineer) TO KEVIN O DONNELL (Developer) TO BE SUPPLIED TO WAIMAKARIRI DISTRICT COUNCIL (Territorial authority) IN RESPECT OF SUBDIVISION OF Pt. LOT 1 DP (Description of infrastructure/land development) AT 29 PETRIES ROAD,WOODEND I _STEVEN MURRAY ELLIS ROBERTS of (full name) KIRK ROBERTS CONSULTING ENGINEERS LTD (name and address of firm) Hereby confirm that 1. I am a suitably qualified and experienced geotechnical engineer and was retained by the developer as the geotechnical engineer on the above development 2. The extent of my inspections during construction, and the results of all tests carried out are as described in Kirk Roberts Ltd s Report dated 9 th March In my professional opinion, not to be construed as a guarantee, I consider that (delete as appropriate) a. The earthfill shown on the attached Plan No N/A have been placed in compliance with the requirements of the N/A Council and my specification. b. The completed work give due regard to land slope and foundation stability considerations. c. The original ground not affected by filling is suitable for the erection thereon of buildings designed according to NZS provided that i. Scala Penetrometer tests are carried out to confirm if the near-surface soils to 2 m depth provide a ii. Geotechnical Ultimate Bearing Capacity of no less than 2kPa. N/A

56 d. the filled ground is suitable for the erection thereon of buildings designed according to NZS provided that i. N/A ii. N/A e. The original ground not affected by filling is suitable for the construction of a development/subdivision and are not subject to erosion, subsidence of slippage in accordance with the provisions of Section 16 of the Resource Management Act 1991 provided that i. N/A ii. NOTE The sub-clause in Clause 3 may be deleted or added to as appropriate. 4. This professional opinion is furnished to the territorial authority and the developer for their purposes alone, on the express condition that it will not be relied upon by any other person and does not remove the necessity for the normal inspection of foundation conditions at the time of erection of any building. 5. This certificate shall be read in conjunction with my geotechnical report referred to in Clause 2 above, and shall not be copied or reproduced except in conjunction with the full geotechnical report referred to in Clause 2 above, and shall not be copied or reproduced except in conjunction with the full geotechnical completion report. 6. My practice holds a current policy of Professional Indemnity Insurance no less than $5,. (the minimum amount of insurance shall be commensurate with the current amounts recommended by IPENZ, ACENZ, TNZ, INGENIUM.) (signature of engineer) Date 9 March 212 Qualifications and experience CPEng; MIPENZ; IntPE(NZ) Practicing as a Geotechnical Engineer