SOIL CONSULTANTS, ENGINEERS & GEOLOGISTS. Since P.O. Drawer 698 Charleston, South Carolina / Fax

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1 SOL COSULTATS, C. EGEERS & GEOLOGSTS Cnstructin Malerlals n Destructive Getechnical Envirnmental Since 95 P.O. Drawer 698 Charlestn, Suth Carlina / Fax Palmett Gunite Cnstructin Cmpany, nc_ P.O. Bx 388 Ravenel, SC Attentin: MT.Bill Snw Reference: Prpsed Stair and Elevatr n:fill Cnnectin Building, King and Wentwrth Streets, Charlestn, Suth Carlina Reprt umber: Dear Mr. Snw: The fllwing reprt is given fr the static pile lateral lad test cnducted n July , at the site f the abve referenced prject This reprt prviq-esa general discussin f the tested pile, the system used t install the micr-pile, the lad test equipment. and the lad test results. Lateral lading f deep fundatins can be caused by earthques. scur, ship impact. and wind, and usually is the driving factr in the design f piles and drilled shafts in areas where these hazards might exist. lrallads.- Methds fr predicting the capacity f a single pile subjected t are quite reliable, and many full scale pile tests have been cnducted in the field t verify and refine the methds. Prject nfrmatin The site is lcated in dwntwn Charlestn and is bunded by existing buildings n all sides. Access t the site is between 75 and 77 Wentwrth Street. Based n infrmatin prvided, the prpsed develpment will include a 4-stry building that will cnnect t existing buildings and huse an elevatr, stairway and cnnecting hallway and lbby areas.

2 Palmett Gunite Cnstructin Cmpany, nc Page 2 Subsurface Cnditins The subsurface explratin fr the site was cnducted by Sil Cnsultants, nc. () and is described in ur Reprt f Fundatin Explratin ( Prject 0698) dated May 22, The sil bring perfrmed fr this prject generally encuntered very lse t dense fine t medium sands t a depth f 28 feet. Standard penetratin resistance () values btained in the sands ranged frm 2 t 38 blws per ft. n additin, an interbedded very sft clay stratum with an value f 2 blws per ft was encuntered at a depth f 4Y2t 9Y2feet. At a depth f 28 feet, the sands were underlain by sft t stiff inrganic clays, with values ranging frm 3 t 4 blws per ft, t a depth f 63 feet. Underlying the clays, stiff t very stiff sediments f the Cper Marl frmatin, with values ranging frm 9 t 30 blws per ft. extended t terminatin f the bring at 0Y2feet. Fundatin Selectin Based n the pr subsurface cnditins described abve and the prvided design data. we recmmended that the prpsed building be supprted n deep fundatins. Several alternative pile types were recmmended, but steel micrpiles were selected due t the cnfined nature f this site. TTA njectin Bre (BO) micr piles were installed t a depth f 23 feet as recmmended. As part f ur riginal reprt fr this prject, a lateral lad capacity analysis was perfrmed using LPLE sftware, which emplys p-y analysis t determine the deflectins at the grund surface f a single pile under specific lading cnditins. The lateral lad was assumed t be applied at the grund surface t the butt f the pile under a free-head lading cnditin fr the steel micr pile. Based n this LPLE analysis, the design lateral capacity fr the micr-piles was 0.5 tns. Using a factr f safety f2.0, the required ultimate capacity is tn. TT A BO micr-piles cnsist f TTA rn 40/20 steel rds, manufactured by Cnstructin Technlgy Systems Limited f Clearwater, Flrida. The TTA steel rds are made f StE 460 micr-ally steel, with a yield strength (Fy) f apprximately 67 kips per SOL COSUl.:rATS, C /

3 Palmett Gunite Cnstructin Cmpany, nc Page 3 square inch (ksi). A 50 millimeter (5.9 inch) diameter cutting head was used t drill the pile t the specified depth. During drilling, a lean cement grut, cnsisting f Type Prtland Cement..is pumped thrugh the ma rn rds, frming a clumn f grut surrunding the steel rds. The design cmpressive strength f the grut was 3,500 punds per square inch (psi). The seven day cmpressive strength f the grut as determined by frm grut cubes btained during installatin prir t cmmencement f the lad test was 3,750 psi. The 28 day cmpressive strength average was apprximately 7,35 psi. Static Lateral Lad Test The pile lad test was cnducted in accrdance with ASTM Designatin D 3966, Standard Test Methd fr Piles Under Lateral Lads, and as utlined by paragraph 6.4, Surge Lading, except as mdified herein. The static lad testing instrumentatin cnsisted f attaching a single () dial gage t the tp f the pile. This gage has a range f 2 inches with graduatins f 0.00 inches. n additin, a wire scale was attached t the ram t prvide an additinal methd f measurement fr the lad test. The lad was applied t the pile tp using a hydraulic ram and a reactin system cnsisting f a steel frame rigidly cnnected t tw (2) reactin piles. The reactin piles cnsisted f piles installed identically t the pile being tested. The test pile and the reactin piles were installed in the suth central area f the prject site and these piles were installed specifically fr the pile lad test and will nt be utilized t supprt the prpsed structure. n additin t the tw reactin piles, a Bbcat Mdel T-300 Skidsteer lader with an apprximate weight f 9,300 punds was parked in cntact with the reactin piles t prvide further lateral supprt. A cpy f the hydraulic ram calibratin data is attached. Lad Test Results The test Oateral) pile shwed a maximum deflectin f.235 inches when laded t 6.92 tns, and returned t a deflectin f inches within five minutes f the lad being remved. Determinatin f the ultimate pile capacity frm a static lad test is determined as that lad which causes a grss pile deflectin f inch at the grund surface as utlined in Sectin SOil. COSUL:TATS.C.

4 Palmett Gunite Cnstructin Cmpany, nc Page f the 2003 Editin f the nternatinal Building Cde. This analysis shwed the pile t have an ultimate capacity f apprximately 6 tns. Based n these test results, the 2003 BC states that the allwable lateral capacity f this pile is ne half f the ultimate strength r 3 tns. The graphs belw shw bth the pile deflectin versus lad and lad versus time plts. Lateral Deflectin v Lad c 0.6 -u O.8 -Q) Cl t4 \c Lad (tns) ' Lateral "" ""/ V Deflectin v Lad 8 SOL COSULATS. C.

5 Palmett Gunite Cnstructin Cmpany, nc Page 5 Deflectin and Lad Lad (tns) 246 'E, t: -,E 5 20.J J r - J en 5 -Lad 0 ] c:: 5 'E - en 20 E i= 25 v Time r- 30 Deflectin v Time Deflectin (in) Lateral Pile Analysis The. results f the lateral lad test were used t refine ur micr-pile mdel that was perfnned using LPLE sftware as part f the riginal reprt fr this prject. Adjustments t the LPLE micr-pile mdel included increasing the pile diameter and assciated pile prperties and selectin f an analysis type different frm the basic mdeling analysis. n rder t match the results f the lateral lad test, the pile diameter inputted int the LPLE prgram SOL C:OSULATS. C.

6 Palmett Gunite Cnstructin Cmpany, nc Page 6 was increased t 9 inches. n additin, Analysis Type 3 - Cmputatin f Mment - Curvature Relatins and minal Mment Capacity and Pile Respnse Using nlinear E was selected. Fllwing adjustments t the LPLE mdel, the lateral pile analysis was perfrmed again assuming an axial lad f 5 tns with a maximum displacement f inch fr a 23-ft lng micr-pile. The results f the ultimate lads are shwn n the attached graphs. As shwn, the ultimate lateral capacity based n LPLE mdeling is 5.9 tns. Thank yu fr allwing us t be f service t yu n this prject, and we lk frward t wrking with yu in the future. Sincerely, SOL COSUL TAmS, C. djh SOL COSUU"ATS.C

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