清华大学：Structural option for the Jinping neutrino central detector

Structural option for the Jinping neutrino central detector Contributor: Yuanqing wang, Zongyi wang Speaker: Zongyi wang Department of civil engineering, Tsinghua University 2015-06-05

Structural option for the Jinping neutrino central detector Contributor：YuanqingWang, Zongyi Wang Speaker： Zongyi Wang Department of civil engineering, Tsinghua University 2015-06-05 1

Outline 1. Introduction of the whole structure 2. Bearing capacity of the local ioint 3. Introduction of the 1 t scale model

Outline 1. Introduction of the whole structure 2. Bearing capacity of the local joint 3. Introduction of the 1 t scale model 2

Introduction of the whole structure Project introduction The structure is placed at 2400 m underground. 500 t(x2)or 100 detecting liquid(density 0.8-1 g/cm )is contained by an acrylic vessel l and water with the density of 1.0 g/cm is outside the acrylic. The acrylic vessel is supported by a stainless steel latticed shell Two alternative options (1) Cylindrical scheme (2)SpHerical scheme

Two alternative options: The structure is placed at 2400 m underground. 500 t (2) or 1000 t detecting liquid (density 0.8-1 g/cm3 ) is contained by an acrylic vessel and water with the density of 1.0 g/cm3 is outside the acrylic. The acrylic vessel is supported by a stainlesssteel latticed shell. Project introduction Introduction of the whole structure 3

Introduction of the whole structure 三 Include pmt No PMt Cylindrical scheme(study in progress) Diameter of acrylic vessel 1l m, height 11 m Diameter of latticed shell 16 m. height 16 m fiducial capacity of the vessel 572 t

Include PMT No PMT Cylindrical scheme (study in progress) ➢ Diameter of acrylic vessel 11 m，height 11 m ➢ Diameter of latticed shell 16 m，height 16 m ➢ Fiducial capacity of the vessel 572 t Introduction of the whole structure 11 m 16 m 4

Introduction of the whole structure C■N Include pmt NO PMT lerical scheme(study in progress Diameter of acrylic ball 12 Diameter of latticed shell 17 m I Fiducial capacity of the vessel 523t

Spherical scheme (study in progress) ➢ Diameter of acrylic ball 12 m ➢ Diameter of latticed shell 17 m ➢ Fiducial capacity of the vessel 523 t Introduction of the whole structure Include PMT No PMT 12 m 17 m 5

Design experience for JUNO central detector At 700 m underground Diameter of ball 35.5 m. thickness 120 mm Diameter of stainless steel: inner 38.5 m outer 40.5 m 20 thousands of liquid scintillator(0.866g/cm3 inside water outside(lg/cm). 15,000 PMT mounted on the latticed shell 二三三三三三三三二二二二二 I Working condition Structural self weight self weight and buoyancy I of PMT+ pressure difference on the acrylic ball Acrylic vessel double-layer stainless steel

Acrylic vessel + double-layer stainless steel ➢ At 700 m underground ➢ Diameter of ball 35.5 m，thickness 120 mm ➢ Diameter of stainless steel：inner 38.5 m， outer 40.5 m. ➢ 20 thousands of liquid scintillator (0.866g/cm3 ) inside, water outside (1g/cm3 ). 15,000 PMT mounted on the latticed shell. Working condition: Structural self weight + self weight and buoyancy of PMT + pressure difference on the acrylic ball Design experience for JUNO central detector 6

Design experience for JUNO central detector Dividing method Along the latitude line: 24 Along the longitude line: 15 The point on the inner latticed shell The point on the outer latticed shell Number of the braces 564 Lighting-blocking rate: 1.8%

The point on the inner latticed shell The point on the outer latticed shell Number of the braces: 564 Lighting-blocking rate: 1.8% Dividing method Along the latitude line：24 Along the longitude line：15 7 Design experience for JUNO central detector

Design experience for JUNO central detector The numerical model was created and evaluated using the abaQus S, Mies (Awg: Maximum stress on the Maximum stress on the ball: 5.4MPa latticed shell: 82.7 MPa Wom: Singular points excluded: 3.9 MPa MaX:B2.724 Elem: WHOLE-1 7244 SF SF1 24 Maximum axial force of Max:24.458 Node: WHOLE-. 6403 Maximum displacement Node: 817 braces: 134.6KN of structure: 24.5 mm 1/1428 x:134596.734 Strength analysis

The numerical model was created and evaluated using the ABAQUS Maximum stress on the ball: 5.4 MPa Singular points excluded: 3.9 MPa Maximum stress on the latticed shell: 82.7 MPa Maximum axial force of braces: 134.6 KN Maximum displacement of structure: 24.5 mm 1/1428 Strength analysis 8 Design experience for JUNO central detector

Design experience for JUNO central detector Stability analysis Material nonlinearity+ geometric nonlinearity, the initial imperfection is taken as 1/300 of the span. 0.07 Node: WHOLE-1. 26123 Deflection of feature point (mm) Eigenvalue of the lst buckling mode 43>4.2 Load factor 2.12>2.0 Technical specification for space frame structures?

Stability analysis Eigenvalue of the 1 Load factor 2.12 > 2.0 st buckling mode 4.3 > 4.2 Material nonlinearity + geometric nonlinearity， the initial imperfection is taken as 1/300 of the span. “Technical specification for space frame structures” 0 50 100 150 200 250 300 0 1 2 Load factor Deflection of feature point（mm） 9 Design experience for JUNO central detector

Bearing capacity of the local joint Test purpose: Stainless-steel fastener Bearing capacity Patched acrylic Deformation ability Failure mode Schematic diagram Load in Juno: 14 t 100 t tensile jack Joint 1 Joint 2 Joint 3 10

Schematic diagram Joint 1 Patched acrylic Stainless-steel fastener Main acrylic Joint 2 Joint 3 Bearing capacity of the local joint Test purpose: ➢ Bearing capacity ➢ Deformation ability ➢ Failure mode Load in JUNO: 14 t 100 t tensile jack 10